10 Reasons Why Bridges Collapse

You may not think about the bridges you cross on your way to work, but they’re far more than pretty structures that make your commute manageable. Bridges are crucial transportation links that carry road and rail traffic across rivers, gorges or other roads. When a bridge collapses or closes for repairs, it can cause massive traffic problems or strand people altogether, if they live on an island.

Some of the most massive and expensive engineering projects in history have involved building bridges. Although the general physics of bridge-building have been established for thousands of years, every bridge presents complicated factors that must be taken into consideration, such as the geology of the surrounding area, the amount of traffic, weatherand construction materials. Sometimes these factors are miscalculated, or something occurs that the bridge designers didn’t expect. The result can be tragic.

As we go through this list of 10 reasons why bridges collapse, keep in mind that most bridge collapses are the result of multiple factors. For example, a flood that damages bridge piers might not have caused a collapse — except for a design flaw and poor maintenance. Remove one of those factors and the bridge may have remained upright. On the other hand, sometimes a train smashes into a bridge and it just falls down. We’ll consider the possibilities, starting on the next page.

10. Earthquake

Earthquakes cause damage to all structures, including bridges. Major earthquakes can bring about the collapse of dozens of buildings, but collapsed bridges are often the most visible signs of the havoc an earthquake can wreak. Amidst the rubble and devastation, the sight of a damaged bridge from TV news helicopters stands out and becomes the iconic image of that particular disaster.

Such is the case with the Loma Prieta earthquake that struck the California coastal cities of Oakland and San Francisco in October 1989. The earthquake — named for a nearby mountain — caused 63 deaths, and the majority of them occurred in two bridge collapses: One person died as a section of the San Francisco-Oakland Bay Bridge gave way, and 42 others perished when a large portion of the Cypress Street Viaduct carrying Interstate 880 collapsed [source: USGS].

Fortunately, earthquake-triggered bridge collapses are relatively rare. In addition, builders can construct bridges in earthquake-prone areas to withstand tremors — or at least minimize the loss of life when one occurs.

9. Fire

Fire might be the rarest cause of bridge collapses, but fire has brought a few bridges down in the past. In fact, it used to happen much more often, when bridges were made out of wood. Train bridges were especially susceptible to fire, because the steel wheels of the train on the steel rails of the track frequently sent sparks shooting onto the bridge. If it was very dry or the wind fanned the sparks, the bridge could catch fire and burn completely down [source: Letchworth].

Bridge fires aren’t a thing of the distant past, however. Several modern bridges have also collapsed or been severely damaged due to fire. The cause is typically the crash of a tanker truck carrying a large amount of a highly flammable substance like gasoline. The crash triggers an explosion and a blaze so intense it melts the steel used to build the bridge. Eventually, the softened steel can no longer hold up the structure, and the bridge falls.

This is exactly what happened in 2009 when a tanker truck on I-75 near Detroit suddenly burst into flames directly under a bridge. The resulting inferno destroyed the bridge completely and forced the closing of I-75. Amazingly, no one was killed [source: Guthrie].

8.Train Crash

This type of bridge collapse is extraordinarily rare, but one of the worst rail disasters in history, the Eschede train disaster, was a bridge collapse caused by train impact. In 1998, a high-speed train traveling through Germany suffered a mechanical malfunction of one of the wheels. The broken wheel struck a switch and shifted it, throwing subsequent cars onto a different track. Moving at roughly 124 miles (200 kilometers) per hour, the cars derailed and slammed into the piers of a road bridge that passed over the railroad tracks at that point. The massive impact brought the bridge down directly onto the passenger cars of the train, crushing them. As a result, 101 people died in the accident [source: Oestern]. Eighty-three people lost their lives in a similar tragedy near Sydney, Australia in 1977 [source: ABC News].

Even rarer than trains crashing into bridges are airplane crashes that destroy bridges. The 1982 crash of Air Florida Flight 90 hit the 14th Street Bridge over Interstate 395 near Washington National Airport, killing several people in their cars. The bridge did not completely collapse, but did require extensive repairs [source: Wilber].

7. Boat Impact

Many bridges cross rivers and other bodies of water. Boats passing under a bridge are usually moving pretty slow (compared to trains), but boats have incredible mass. This means that even a barge, which typically creeps along at very slow speeds, can impart tremendous force if it collides with bridge pilings or piers. That force is sufficient to knock down the bridge in some cases.

An example of this type of incident is the collapse of the Judge William Seeber Bridge in New Orleans in 1993. The bridge carried road trafficover a canal, and a barge passing under the bridge struck a pier supporting the bridge and severed it. Nearly 150 feet (46 meters) of bridge collapsed as a result. One motorist driving on the bridge at the time died in the accident [source: NTSB]. More than a dozen major bridge collapses have been caused by boat collisions in the last 100 years [source: Wardhana].

6.Flood

Floods cause bridge collapses in a few different ways. Severe floods can cause rivers and creeks to overflow, picking up debris like trees, cars and parts of houses. When the river passes under a bridge, the high water level smashes the debris into the bridge. If the impact doesn’t destroy the bridge immediately, the weight of the piled up combined with the force of the flowing water pushing on it can bring the bridge down. This is what happened to the Conemaugh Viaduct in 1889, when the South Fork Dam in Pennsylvania collapsed, unleashing a massive torrent of water down the Little Conemaugh River [source: NPS].

Flooding can collapse bridges in a far more insidious way — by gradually wearing away the earth around and underneath the bridge piers. This process is known to bridge engineers as scour, and occurs whenever bridge foundations are placed underwater. The natural flow of the water can produce scour over many years, but bridges are built to withstand that type of erosion. Engineering techniques such as laying riprap, or layers of heavy rocks, can prevent scour. However, floods dramatically increase the force and volume of water affecting the bridge, and the damage to sediments can cause a bridge to collapse immediately or even days or months later. A study by the American Society of Civil Engineers determined that 53 percent of all bridge collapses are caused by flood and scour [source: Wardhana].

he Schoharie Creek Bridge is an example of a collapse caused by flood and scour. The bridge carried the New York State Thruway over the creek. In 1987, spring flooding caused high water levels. This washed sediment out from under one of the bridge piers, causing it to fall into a hole nearly 10 feet (3 meters) deep. Ten people died in the resulting bridge collapse [source: Storey & Delatte].

5. Construction Accidents

The Quebec Bridge collapsed twice during construction before finally being built.

A surprising number of bridges collapse as they’re being built. You might think these types of collapses aren’t as serious because no one was driving on the bridge at the time of the collapse. Unfortunately, some of the deadliest bridge collapses in history have occurred during the bridge’s construction. While a functional bridge may only have a few vehicles on it when it collapses, it takes hundreds of workers to build a bridge — all of whom may be in dangerous positions in case of collapse.

The 1907 collapse of the Quebec Bridge crossing the St. Lawrence River at Quebec City shows how engineering miscalculations can lead to disaster. The bridge was only partially constructed, but parts were already bending and breaking from the weight of the bridge itself. Engineers were concerned, but unable to take action swiftly enough. When it collapsed, 74 workers were killed [source: Structurae]. Amazingly, when the bridge was being rebuilt in 1916, it collapsed again, killing 13 more workers. It was finally completed in 1917 and remains in use today.

4. Manufacturing Defect

Some bridge collapses are mysteries when they first happen. It isn’t until a detailed investigation is completed that the true cause is revealed. Combing over the wreckage, engineers and accident investigators piece together the bridge’s history, looking at inspection reports and witness accounts of the collapse. At times, the simple failure of a small piece of the bridge caused the entire collapse. Sometimes low-grade or faulty materials were used, rendering the entire bridge too weak to withstand the rigors of time.

The 1967 collapse of the Silver Bridge over the Ohio River at Point Pleasant, W. Va. has become infamous for its connections to Mothman, a strange creature supposedly sighted near Point Pleasant in the months prior to the collapse (The 2002 Richard Gere film “The Mothman Prophecies,” chronicled the story). In truth, the collapse was due to a manufacturing defect in one of the steel eyebars that held the bridge up. Years of corrosion worsened the defect until it eventually failed, resulting in the deaths of 46 people [source: LeRose].

The 1994 collapse of the Seongsu Bridge in Korea was due to poor quality steel in some parts of the bridge and improper welding techniques in the bridge’s construction. 32 people were killed in the collapse [source: Korea National Emergency Management Agency]. The De la Concorde overpass in Laval, Quebec, Canada collapsed in 2006, killing five. The investigation revealed that some aspects of the bridge’s construction were done incorrectly and not according to the design, and that inferior quality concrete became too weak to support the structure.

3. Design Defect

Sometimes, bridges collapse due to design flaws

There are bridges whose collapse was inevitable before the bridge was ever built. The fault lies not with the construction of the bridge, but the design itself. The bridge is doomed to failure from the moment it was laid out on a blueprint.

One of the worst accidents in U.S. history is the collapse of the walkways in the Kansas City Hyatt Regency hotel. The walkways connected various parts of the second, third and fourth floors, overlooking the hotel lobby below — they were essentially pedestrian bridges inside the hotel. On July 17, 1981, the fourth-floor walkway collapsed, crashing onto the second-floor walkway which was directly below it. Both walkways then fell onto the lobby. Both the lobby and walkways were crowded with people watching or participating in an evening dance contest. The collapse killed 114 people [source: Associated Press].

Why did it happen? A redesign of the original plan caused the walkways to be constructed in such a way that structural elements ended up supporting the weight of both the second and fourth floor walkways simultaneously, doubling the load on them. Investigation revealed that even the original design was far too weak to support significant loads — and the redesign made the problem much worse [source: Martin]. It was nearly inevitable that they would collapse at the worst possible moment.

The 2007 collapse of the I-35 Bridge over the Mississippi River in Minneapolis, Minn. was also due to a design flaw. Steel gusset plates which bound key parts of the bridge structure together weren’t large enough. Additional weight placed on the bridge by concrete resurfacing and construction equipment caused the plates to buckle, and the entire bridge collapsed, killing 13 [source: NTSB].

2. Poor Maintenance

Poor maintenance is a difficult problem to diagnose in the wake of a bridge collapse. Many bridge collapses could have been prevented with more stringent inspection and maintenance routines, and lots of collapses that occur for other reasons are exacerbated by poor maintenance. When a bridge is designed, the engineers assume a certain level of maintenance that is necessary for the bridge to live out its intended lifespan. Rusted parts must be replaced, drainage areas cleared, new coats of paint applied and reinforcements added if traffic levels have increased.

A bridge carrying the Connecticut Turnpike over the Mianus River collapsed in the middle of the night in June 1983. The collapse was due to the failure of steel pins that had corroded. Investigators ruled that the bridge’s design and construction weren’t at fault — the collapse was blamed on deferred maintenance that would have spotted and replaced the rusted pins [source: NYCRoads].

1. Odd Occurrences

Some bridge collapses just can’t be explained at all.

We’ve discussed many causes of bridge collapse, but there are collapses that weren’t caused by any of the usual factors — rather, they were caused by events that can only be described as unusual.

In 1958, Cuba held the second Cuban Grand Prix. Legendary racer Juan Fangio was actually kidnapped by socialist revolutionaries before the race, but that wasn’t the worst thing about the event. The course was lined not with guard rails or safety fences, but with spectators standing right at the edge of the track. During the race, driver Armando Garcia Cifuentes lost control of his Ferrari and plowed into the crowd, destroying a temporary pedestrian bridge in the process. Seven people were killed [source: Edmondson].

The Lacey V. Murrow Memorial Bridge in Seattle crosses Lake Washington. It’s a floating bridge, suspended on pontoons. In 1990, a bizarre series of construction errors filled the pontoons with water used in resurfacing the bridge along with rain and lake water from a storm. Over the course of several hours, the bridge sank to the bottom of the lake.

The Winkley Bridge was a pedestrian suspension bridge in Arkansas. It was known for swaying significantly under load. In 1989, a group crossing the bridge started intentionally swinging it. They caused the bridge to sway so fiercely that the support structures failed and the bridge collapsed, killing five [source: Bridgehunter].

Introduction of Building Information Modeling (BIM) Technologies in Construction

Introduction of Building Information Modeling (BIM)
Technologies in Construction

1. Introduction

BIM (Building Information Modeling) — information modeling of buildings, which allows one to model not only the construction objects themselves, but also their characteristics, as well as all possible changes in time — is persistently introduced to the construction industry [1–6].

In practice, the use of BIM technology is integrated into all stages of production and life support of buildings: data collection, design work, construction, equipment, operation, repair work and demolition. That is, all the necessary information is located in the computer models: architectural, construction, technological, economic, etc.

In the work of Z. Pezeshki and S. A. S. Ivari [7], a classification and review of the literature from 2000 to 2016 on building information modeling (BIM) are provided. It is shown how various methodologies of BIM were developed during this period. Three main types of future trends of methodology development of information modeling and related research and development are noted by the authors:

• BIM methods, as a rule, are developed in the direction of expertise.
• It is proposed to implement various social science methodologies using BIM as another type
of methodology.
• The ability to constantly change and learn is the driving force of BIM’s methodologies and
will become the key to future intellectual applications.

Work [8] is directed towards the development of the discriminant model of readiness for introduction of BIM to a construction organization. For empirical check of the proposed model, the authors received 164 questionnaires filled out by construction organizations with the involvement of contractors, architects, heads of construction and engineers.

In work [9], the issue of application of cloud technologies as a necessary tool for further development of building information modeling technologies is considered. The issues of data management, introduction of new technologies and interaction of participants of the BIM-process are analyzed.

In review [10], the main focus is on the identification of the future tendencies for development of the process of building design, taking into account building information modeling (BIM) technology.

The authors note that nowadays the use of BIM technologies is widely implemented both into the construction industry, and into the academic environment. The benefits of BIM, such as systematicity of the modeling process, a powerful platform for interactive visualization and standardized data exchange are shown in the study.

2. Materials and methods

The result of the building information modeling is an object-oriented digital model both of the whole object and the process of its construction. First of all, it allows one to assemble the components and systems of future construction created by different specialists and organizations in the virtual mode, selecting them according to purpose, perform corresponding calculations, alignment and coordination, check their viability, functional suitability and operational qualities in advance, and also avoid internal disagreements (collisions) unpleasant for designers [2].

The most important advantage of BIM technology is the complete interdependence of all types of information, each of which is updated automatically upon a single introduction of any changes . And the created information model may be a computer model of a real building throughout its life and reflect all the changes and additions of the current and future state.

The main competitive quality of BIM technology is significant cost savings, first of all, due to theincrease in speed of design; besides it is possible to talk about creation of quite complex and unique objects . The process of information modeling divides the design work into two stages:

1. Development of primary design objects, both construction (windows, doors, floor slabs, wall
types, roof types, etc.), and elements of different systems (heating, ventilation, electricity, water
supply, sewerage, etc.), which include all necessary technical and economic characteristics.

2. Modeling of the object itself, which occurs in the form of customary formation of technical
drawings and specifications of layouts, sections, facades, three-dimensional views and other forms of
information presentation.

In March 2015, the «Plan of a step industrial and civil construction» was approved by the order of the Ministry of Construction and Housing and Communal Services of the Russian Federation.

Implementation of this plan is associated with the significant changes in the whole construction industry, affecting every smallest part of it. Besides, a detailed interaction of these smallest parts is an essence of BIM, as huge reserves lie in maximum automation when moving information from one link in a significant reduction in the project cost [11].

According to the above mentioned plan, since 2020, the use of information modeling technologies (BIM) in the design, construction and operation of buildings and structures constructed from the budget of the Russian Federation will be mandatory.

A uniform information space shall be built on a platform of national standards, and these standards have to harmoniously fit into already existing world standards. All construction products, structural elements, materials and types of work have to be connected with this standard using electronic qualifiers. It is necessary to connect all object element libraries with the electronic directories of cost indexes and labor costs. And at present, this work has already begun [11].

3. Conclusion

Information systems in the organizations and construction industry enterprises, functioning within the concept of information modeling, require significant expenditures for the introduction of a new approach towards design and support of the construction process. Certainly, the details of a new approach can be accepted only after a careful elaboration of pilot projects, which should identify the ways and means of verification of the regulatory and technical base, as well as economic indicators.

References

[1] Ferrandiz J, Banawi A and Peña E 2017 Evaluating the benefits of introducing “BIM” based on Revit in construction courses, without changing the course schedule Universal Access in the Information Society doi: 10.1007/s10209-017-0558-4
[2] Mainicheva A Y, Talapov V V and Zhang G 2017 Principles of the information modeling of cultural heritage objects: the case of wooden Buddhist temples Archaeology, Ethnology & Anthropology of Eurasia 45(2) 142–148 (in rus) doi: 10.17746/1563-0110.2017.45.2.142-148
[3] Sharmanov V V, Simankina T L and Mamaev A E 2017 BIM in the assessment of labor protection Magazine of Civil Engineering (1) 77–88 doi: 10.18720/MCE.69.7
[4] Luo H, Gong P 2015 A BIM-based Code Compliance Checking Process of Deep Foundation Construction Plans Journal of Intelligent & Robotic Systems 79(3–4) 549–576 doi: 10.1007/s10846-014-0120-z.
[5] Chegu Badrinath A, Chang Y, Hsieh S 2016 A review of tertiary BIM education for advanced engineering communication with visualization Visualization in Engineering 4(1) doi: 10.1186/s40327-016-0038-6.
[6] Soust-Verdaguer B, Llatas C, García-Martínez A 2017 Critical review of BIM-based LCA method to buildings Energy and Buildings 136 110–120 doi: 10.1016/j.enbuild.2016.12.009.
[7] Pezeshki Z, Ivari S A S 2016 Applications of BIM: A Brief Review and Future Outline Archives of Computational Methods in Engineering doi: 10.1007/s11831-016-9204-1
[8] Lee S, Yu J 2017 Discriminant model of BIM acceptance readiness in a construction organization KSCE Journal of Civil Engineering 21(3) 555–564 doi: 10.1007/s12205-016-0555-9
[9] Alreshidi E, Mourshed M and Rezgui Y 2016 Requirements for cloud-based BIM governance solutions to facilitate team collaboration in construction projects Requirements Engineering doi: 10.1007/s00766-016-0254-6
[10] Chi H-L, Wang X and Jiao Y 2015 Archives of Computational Methods in Engineering 22(1) 135–151 doi: 10.1007/s11831-014-9127-7
[11] Kapitonova T G 2016 BIM-technology as a near-term prospect of the construction industry Architecture – construction – transport: Materials of the 72nd scientific conference of professors, teachers, scientists, engineers and post-graduates of the University (SaintPetersburg: SPbSUACE) 1 pp 18–22 (in rus)

Source:

M A Milyutina
Saint Petersburg State University of Architecture and Civil Engineering, 4, 2nd Krasnoarmeyskaya St., Saint-Petersburg, 190005, Russia

Pavement Defects and Failures You Should Know!

Pavement deterioration is the process by which distress (defects) develop in the pavement under the combined

effects of traffic loading and environmental conditions.

I. Types of pavement deterioration:

The four major categories of common asphalt pavement surface distresses are:

1.Cracking

2.Surface deformation

3.Disintegration (potholes, etc.)

4.Surface defects (bleeding, etc.)

1.Cracking:

The most common types of cracking are:

a.Fatigue cracking

b.Longitudinal cracking

c.Transverse cracking

d.Block cracking

e.Slippage cracking

f.Reflective cracking

g.Edge cracking

a. Fatigue cracking (Alligator cracking):

Fatigue cracking is commonly called alligator cracking. This is a series of interconnected cracks creating small, irregular shaped pieces of pavement. It is caused by failure of the surface layer or base due to repeated traffic loading (fatigue). Eventually the cracks lead to disintegration of the surface, as shown in Figure. The final result is potholes. Alligator cracking is usually associated with base or drainage problems. Small areas may be fixed with a patch or area repair. Larger areas require reclamation or reconstruction. Drainage must be carefully examined in all cases.

b. Longitudinal cracking:

Longitudinal cracks are long cracks that run parallel to the center line of the roadway. These may be caused by frost heaving or joint failures, or they may be load induced. Understanding the cause is critical to selecting the proper repair. Multiple parallel cracks may eventually form from the initial crack. This phenomenon, known as deterioration, is usually a sign that crack repairs are not the proper solution.

c. Transverse cracking :

Transverse cracks form at approximately right angles to the centerline of the roadway. They are regularly spaced and have some of the same causes as longitudinal cracks. Transverse cracks will initially be widely spaced (over 20 feet apart). They usually begin as hairline or very narrow cracks and widen with age. If not properly sealed and maintained

, secondary or multiple cracks develop, parallel to the initial crack. The reasons for transverse cracking, and the repairs, are similar to those for longitudinal cracking. In addition, thermal issues can lead to low- temperature cracking if the asphalt cement is too hard. Figure shows a low-severity transverse crack.

d. Block cracking:

Block cracking is an interconnected series of cracks that divides the pavement into irregular pieces.

This is sometimes the result of transverse and longitudinal cracks intersecting. They can also be due to lack of

compaction during construction. Low severity block cracking may be repaired by a thin wearing course. As the

cracking gets more severe, overlays and recycling may be needed. If base problems are found, reclamation or reconstruction may be needed. Figure shows medium to high severity block cracking.

e.Slippage cracking:

Slippage cracks are half-moon shaped cracks with both ends pointed towards the oncoming vehicles.

They are created by the horizontal forces from traffic. They are usually a result of poor bonding between the

asphalt surface layer and the layer below .The lack of a tack coat is a prime factor in many cases. Repair requires removal of the slipped area and repaving. Be sure to use a tack coat in the new pavement.

f. Reflective cracking:

Reflective cracking occurs when a pavement is overlaid with hot mix asphalt concrete and cracks reflect up through the new surface. It is called reflective cracking because it reflects the crack pattern of the pavement structure below. As expected from the name, reflective cracks are actually covered over cracks reappearing in the surface. They can be repaired in similar techniques to the other cracking noted above. Before placing any overlays or wearing courses, cracks should be properly repaired.

g. Edge cracking:

Edge cracks typically start as crescent shapes at the edge of the pavement. They will expand from the edge until they begin to resemble alligator cracking. This type of cracking results from lack of support of the shoulder due to weak material or excess moisture. They may occur in a curbed section when subsurface water causes a weakness in the pavement. At low severity the cracks may be filled. As the severity increases, patches and replacement of distressed areas may be needed. In all cases, excess moisture should be eliminated, and the shoulders rebuilt with good materials. Figure shows high severity edge cracking.

2. Surface deformation:

Pavement deformation is the result of weakness in one or more layers of the pavement that has experienced movement after construction. The deformation may be accompanied by cracking. Surface distortions can be a

traffic hazard.

The basic types of surface deformation are:

a.Rutting

b.Corrugations

c.Shoving

d.Depressions

e.Swell

a. Rutting

Rutting is the displacement of pavement material that creates channels in the wheel path. Very severe rutting will actually hold water in the rut. Rutting is usually a failure in one or more layers in the pavement. The width of the rut is a sign of which layer has failed. A very narrow rut is usually a surface failure, while a wide one is indicative of a subgrade failure. Inadequate compaction can lead to rutting. Figure shows an example of rutting due to subgrade Failure. Minor surface rutting can be fille d with micropaving or paver-placed surface treatments. Deeper ruts may be shimmed with a truing and leveling course, with an overlay placed over the shim. If the surface asphalt is unstable, recycling of the surface may be the best option. If the problem is in the subgrade layer, reclamation or reconstruction may be needed.

b. Corrugation

Corrugation is referred to as wash boarding because the pavement surface has become distorted like a washboard. The instability of the asphalt concrete surface course may be caused by too much asphalt cement, too much fine aggregate, or rounded or smooth textured coarse aggregate. Corrugations usua lly occur at places where vehicles accelerate or decelerate. Minor corrugations can be repaired with an overlay or surface milling.

Severe corrugations require a deeper milling before resurfacing.

c. Shoving

Shoving is also a form of plastic movement in the asphalt concrete surface layer that creates a localized bulging of the pavement. Locations and causes of shoving are similar to those for corrugations. Figure shows an example of shoving. Repair minor shoving by removing and replacing. For large areas, milling the surface may be required, followed by an overlay.

d. Depressions

Depressions are small, localized bowl-shaped areas that may include cracking. Depressions cause

roughness, are a hazard to motorists, and allow water to collect. Depressions are typically caused by localized

consolidation or movement of the supporting layers beneath the surface course due to instability. Repair by

excavating and rebuilding the localized depressions. Reconstruction is required for extensive depressions.

e. Swell

A swell is a localized upward bulge on the pavement surface. Swells are caused by an expansion of the supporting layers beneath the surface course or the subgrade. The expansion is typically caused by frost heaving or by moisture. Subgrades with highly plastic clays can swell in a manner similar to frost heaves (but usually in warmer months). Repair swells by excavating the inferior subgrade material and rebuilding the removed area.

Reconstruction may be required for extensive swelling.

3. Disintegration

The progressive breaking up of the pavement into small, loose pieces is called disintegration. If the isintegration is not repaired in its early stages, complete reconstruction of the pavement may be needed.

The two most common types of disintegration are:

a.Potholes

b.Patches

a. Potholes

Potholes are bowl-shaped holes similar to depressions. They are a progressive failure. First, small fragments of the top layer are dislodged. Over time, the distress will progress downward into the lower layers of the pavement. Potholes are often located in areas of poor drainage, as seen in Figure. Potholes are formed when the pavement disintegrates under traffic loading, due to inadequate strength in one or more layers of the pavement, usually accompanied by the presence of water. Most potholes would not occur if the root cause was repaired before development of the pothole. Repair by excavating and rebuilding. Area repairs or reconstruction may be required for extensive potholes.

b. Patches:

A patch is defined as a portion of the pavement that has been removed and replaced. Patches are usually used to

repair defects in a pavement or to cover a utility trench. Patch failure can lead to a more widespread failure of the surrounding pavement. Some people do not consider patches as a pavement defect. While this should be true for high quality patches as is done in a semipermanent patch, the throw and roll patch is just a cover. The underlying cause is still under the pothole. To repair a patch, a semi-permanent patch should be placed.

Extensive potholes may lead to area repairs or reclamation. Reconstruction is only needed if base problems are

the root source of the potholes.

4. Surface defects:

Surface defects are related to problems in the surface layer. The most common types of surface distress are:

a.Ravelling

b.Bleeding

c.Polishing

d.Delamination

a. Ravelling:

Ravelling is the loss of material from the pavement surface. It is a result of insufficient adhesion between the asphalt cement and the aggregate. Initially, fine aggregate breaks loose and leaves small, rough patches in the surface of the pavement. As the disinteg ration continues, larger aggregate breaks loose, leaving rougher surfaces. Ravelling can be accelerated by traffic and freezing weather. Some ravelling in chip seals is due to improper construction technique. This can also lead to bleeding. Repair the problem with a wearing course or anoverlay.

b. Bleeding:

Bleeding is defined as the presence of excess asphalt on the road surface which creates patches of asphalt

cement. Excessive asphalt cement reduces the skid-resistance of a pavement, and it can become very slippery

when wet, creating a safety hazard. This is caused by an excessively high asphalt cement content in the mix,

using an asphalt cement with too low a viscosity (too flowable), too heavy a prime or tack coat, or an improperly applied seal coat. Bleeding occurs more often in hot weather when the asphalt cement is less viscous (more flowable) and the traffic forces the asphalt to the surface. Figure 13 shows an example of bleeding during hot weather.

c. Polishing:

Polishing is the wearing of aggregate on the pavement surface due to traffic. It can result in a dangerous low friction surface. A thin wearing course will repair the surface.

II. CAUSES OF PAVEMENT DETERIORATION

Sudden increase in traffic loading especially on new roads where the design is based on lesser traffic is major of craking. After construction of good road, traffic of the other roads also shifts to that road. This accelerates the fatigue failure (Alligator Cracking).
Temperature variation ranging from 50°C to below zero conditions in the plain areas of North and Central India leads to bleeding and cracking.
Provision of poor shoulders leads to edge failures.
Provision of poor clayey subgrade results in corrugation at the surface and increase in unevenness.
Poor drainage conditions especially durinng rainy seasons, force the water to enter the pavement from the sides as well as from the top surface. In case of open graded bituminous layer, this phenomenon becomes more dangerous and the top layer gets detached from the lower layers.
If the temperature of bitumen/bituminous mixes is not maintained properly, the it also leads to pavement failure. Over heating of bitumen reduces the binding property of bitumen. If the temperature of bituminous mix has been lowered down the the compaction will not be proper leading to longitudinal corrugations.

Morandi is the fifth bridge to collapse in Italy in five years

Photos from Google Maps taken two years the before the bridge caved in appear to show spot repairs to the concrete, but engineers said the cause of the collapse was more likely to be structural.

A photo shared on Twitter purportedly from the last few weeks also seemed to show issues with the structure — although the image is thought to be from several years ago.

The bridge underwent significant maintenance in the 1980s and 1990s as well as repair works last year and more work was being done on its foundations before the collapse.

An Italian engineering professor appeared to predict the Morandi Bridge disaster two years ago, warning that the bridge was “wrong” and had “errors” and saying it would be cheapest to simply tear it down and rebuild.

Witnesses reported seeing it hit by lightning in a storm just before it collapsed, but experts also dismissed the idea this would be behind the disaster.

Morandi is the fifth bridge to collapse in Italy in five years, according to Corriere Della Sera.

Photos of Morandi bridge before the collapse show black patches believed to be spot repairs to the concrete. Picture: Google MapsSource:Supplied

There were warnings about problems with the structure well before it crumbled. Picture: Google MapsSource:Supplied

Questions have been raised as to whether the Mafia was involved in the bridge’s construction in the 1960s. “Mafia-related companies are known to have infiltrated the cement and reconstruction industries over the decades and prosecutors have accused them of doing shoddy work that cannot withstand high stress,” reported Canada’s Globe and Mail.

In December 2012, the Genoa city council discussed the state of the bridge at a public hearing and a local industry official spoke of its collapse “in 10 years”, according to the BBC.

Italian prime minister Giuseppe Conte on Wednesday declared a state of emergency covering the region around Genoa.

Deputy prime minister Luigi Di Maio said the tragedy “could have been avoided” and blamed operator Autostrade per l’Italia for not carrying out maintenance. The Italian government said it intended to fine the firm $240 million and cancel its licence.

The company insisted it had monitored the bridge quarterly, as required by law.

Transport Minister Danilo Toninelli said it was “unacceptable” and that “whoever made a mistake must pay”, assuming negligence was the cause. He called on the top management of Autostrade per L’Italia to resign.

But Italian media has also pointed to Mr Tonelli’s comments two weeks ago appearing to oppose a major infrastructure project in the area that his deputy Edoardo Rixi said was fundamental.

Questions have been raised as to whether the Mafia could have been involved in the bridge’s construction in the 1960s. Picture: Luca Zennaro/ANSA via APSource:AP

The bridge on a main highway linking Italy with France collapsed during a storm, sending 45 vehicles plunging 45 metres into a heap of rubble below. Picture: Luca Zennaro/ANSA via APSource:AP

DIRE PREDICTION

In 2016, Antonio Brencich, associate professor of civil engineering at the University of Genoa, warned it would cost more to repair the “uneven” construction, rather than just knock the bridge down.

He said maintenance costs “are so exorbitant that it would be cheaper to build a new one”.

“The Morandi Bridge is referred to as a masterpiece of engineering. In reality it is a bankruptcy,” he said in an interview with Italian TV channel primocanale.it. “That bridge is wrong. Sooner or later it will have to be replaced. I do not know when.

“But there will be a time when maintenance costs will exceed those of reconstruction, and then we will have to proceed with the replacement.”

In December 2016, Genoan newspaper Il Secolo XIX claimed bridge restorations were underfunded because authorities “preferred to allocate more funds to new works”.

In a statement following the incident, Italy’s motorway operator Autostrade said the bridge “dates back to the 1960s” and “maintenance works were under way to consolidate it”.

It went on to say that “a bridge-crane was installed to allow maintenance works to be carried out”, adding that “the work and status of the viaduct were subject to constant observation and supervision” by their Genoa division.

“The causes for the collapse will be the subject of an in-depth analysis as soon as it is possible to safely access the site,” the company said.

Genoa Mayor Marco Bucci told CNN the bridge collapse was “not absolutely unexpected”.

“(It’s a) very bad time with the collapsing of the bridge which was not absolutely unexpected. But we don’t know the reason,” he said.

“My role as the mayor is to make sure we have the correct infrastructure for the city and make sure that from the government we get the right amount of money in order to be able to set up the new infrastructure as soon as possible.”

To be continued…

What we know about Genoa bridge that collapsed

The Monrandi bridge in Genoa, Italy is part of the A10 motorway which runs runs over a railway line, riverbed and industrial area.

The road which is close to the French boarder connects the city of Genoa to Savona and Ventimiglia.

Both sides of the highway fell due to severe weather and torrential rain sending cars plummeting to the ground.

It is currently unclear why a section of the Morandi Bridge collapsed. But here’s what do we know about structure:

It’s a highway bridge: The section of the A10 highway affected crosses over several roads, railway tracks, shopping centers, homes and the Polcevera river.
It’s a major thoroughfare: It links central Genoa with Genoa airport and towns along the coast to the west of the city.
It’s long (and tall): The cable-stayed bridge had a total length of 1.1 kilometers and is 100 meters tall at its highest point.
It’s 50 years old: The bridge, also known as the Polcevera Viaduct, was designed by Italian civil engineer Riccardo Morandi and completed in 1968.

The bridge was undergoing maintenance when it collapsed

The bridge that collapsed near Genoa, Italy, was undergoing maintenance, the company in charge of Italian highways, Autostrade, said in a statement on Tuesday.

The Morandi Bridge “dates back to the 1960s” and “maintenance works were underway to consolidate it,” Autostrade said

The statement goes on to say that “a bridge-crane was installed to allow maintenance works to be carried out” adding that, “the work and status of the viaduct were subject to constant observation and supervision” by their Genoa division.

The company added: “The causes for the collapse will be the subject of an in-depth analysis as soon as it is possible to safely access the site.”

Dramatic pictures show the collapsed bridge as rescue workers search the debris.

Emergency services having been working around the clock at the scene.

Italian firefighters said cars and trucks are trapped among the rubble after falling 50 meters to the ground from the Monrandi bridge.

China finalises design of 135km Taiwan rail tunnel

Chinese engineers have finalised a method for building the world’s longest transport tunnel: a 135km link connecting Taiwan with the mainland.

Any live project would depend on a radical change in the international situation – relations between Beijing and Taipei are in the freezer following the election victory of Tsai Ing-wen and the pro-independence Democratic Progressive party in 2016. However, the People’s Republic is planning to have everything in place ready to begin the project when it becomes politically possible.

It would also depend on the two countries’ finding the cost of the scheme, which has been given a speculative cost estimate of $80bn.

According to the South China Morning Post, Chinese engineers are proposing a “warm-up” project to make sure China has the capabilities to tackle what would be one of the most ambitious civil engineering projects of the 21st century.

It is also possible that Beijing will make a symbolic start work on the project without any agreement from the other side of the Formosa Strait .

The idea of a tunnel has been under discussion throughout the 20th century, without any solution emerging for the formidable problems it would face as it cut through complex layers of rock, including granite, and crossed two seismic faults zones.

Possible routes for the tunnel. The Chinese are presently working on the northernmost option (Creative Commons)

The Chinese solution, completed last year with funding from the Chinese Academy of Engineering, would involve sinking the tunnel at least 200m below the surface.

The idea of a link achieved prominence in 2016, when Beijing included the “Beijing–Taipei expressway and rail link” in its 13th five-year plan.

The declaration triggered an emergency session of the Taiwanese legislature and a statement by the Taiwanese government rejecting the idea.

This was followed by a statement from Wang Mengshu, a prominent Chinese railway engineer, claiming that he had been holding secret discussions over the project with his Taiwanese counterparts for a decade, and that then Taiwanese president Ma Ying-jeou, approved of them.

Top image: In the 2016-20 national plan, China proposed extending its high-speed rail system to Taiwan (Alancrh/Creative Commons)

http://www.globalconstructionreview.com

Virgin Hyperloop announces $500m testing centre in Andalucia

Virgin Hyperloop One has signed an agreement with Spain to build a $500m Advanced Technology Development and Testing Centre in the Andalusia.

The facility, which will be the company’s first in Europe, will be partly financed by $146m in public aid through loans and grants on the grounds that the development will stimulate regional economic growth and job creation.

Rob Lloyd, Virgin Hyperloop’s chief executive, said: “By investing in the development and testing of Virgin Hyperloop One, Spain is extending its long-tradition as an innovative, global transport leader. We are excited to partner with such a forward-thinking country in developing the next generation of transportation.”

The plant will be built in the village of Bobadilla in the province of Malaga, part of a cluster of aerospace cluster in Spain. Virgin Hyperloop estimates that it will hire 200-300 technicians.

The plan is to open the 19,000-sq-m in 2020, after which it will work on developing, testing and certifying components and subsystems.

Image: Virgin Hyperloop is part of a global race to bring vacuum maglev technology to market

http://www.globalconstructionreview.com

Roads Paved with Plastic Bottles: Making Use of an Ecological Threat

Rotterdam in the Netherlands may become the first city to repurpose one of Earth’s biggest pollutants by paving its streets with plastic bottles. The Rotterdam City Council is working out a way to efficiently pilot a new type of plastic road surface since their initial declaration in 2015.

The concept raises some concerns. Heat on all-plastic surface may be a problem, as plastic, just like asphalt, can soften under higher temperatures. And the engineers behind the project are working to ensure that the roads are capable of withstanding both the heat and the abuse from constant traffic.

VolkerWessels, a European construction firm, addressed concerns by creating and testing a surface made entirely from plastic. Results suggest that the surface required less maintenance than typical road surfaces and could even withstand extreme temperatures of -40°C to 80°C (-40°F to 176°F).

A Plastic Road Hybrid with Roots in India

While the process is still ongoing in the Netherlands, a UK start-up called MacRebur is succeeding in persuading local councils to use plastic to pave new roads. Cumbria in northwest England has become the first county to turn its local waste into roads.

The project began in a small farmhouse in Lockerbie, Scotland, led by the plastic-road pioneer Toby McCartney.

“We use waste plastics to add into an asphalt mix to create a stronger, longer-lasting pothole free road,” Mr. McCartney says.

Mr. McCartney’s idea came about during his trip to India, where he witnessed the locals pouring plastic into the potholes. The plastic was then burnt into the potholes and smoothed over, fixing the holes and at the same time, making use of the plastic waste. Mr. McCartney left India inspired. But he didn’t act on the idea until until later, back home, when he heard the response his daughter gave when her school teacher asked what lived in our oceans. She said “plastics, miss.” And Mr. McCartney sought to make a change.

How is it done?

The secret lies in a mixture of plastic pellets, but the details are proprietary.

“I give the analogy of Irn Bru, we will never tell anyone what is actually in our mix,” Mr. McCartney says.

Normally, roads are comprised of about 90 percent rocks, limestone and sand, with roughly 10% bitumen used to bind it. Bitumen is extracted from crude oil. The plastic pellets replace a significant part of the bitumen, and can be made from household waste, and commercial waste.

Mr. McCartney regularly receives large bundles of waste, most of which is destined to end up in landfill, or is thrown into the incinerator. The waste plastic however, is processed into millions of pellets at an asphalt plant, where bags of pellets are mixed with quarried rock and bitumen. The result is a road that repurposes plastic waste and lasts longer and costs less than typical roads , Mr. McCartney says.

Can Plastic-Eating Caterpillars Cause Chaos?

The strangest dilemma the might roads face isn’t from the heat, or the weight of the cars. Instead, it may come in the form of hungry caterpillars.

The question arose while researching the possible hazards linked to this innovation in road materials. Plastic-eating caterpillars are a blessing, as their ability to eat through plastic could eventually solve some plastic waste issues. But could they also eat through plastic roads?

Experimenters at Cambridge have discovered that the caterpillars ‘can break down the chemical bonds of plastic in a similar way to digesting beeswax.’ Dr Paolo Bombelli – a scientist as Cambridge University believes that the caterpillars are just the starting point and that “we need to understand the details under which this process operates.”

Alan Read, owner of Ames Pest Control believes that the caterpillars aren’t strong enough to eat through the roads, however:

“The roads look as if they go through multiple safety tests and chemical transformations before being laid onto the roads. Even if thousands of these caterpillars were to focus on eating through one particular section, it would take months, if not years to make a dent. There really is no cause for concern.”

A Bright Future for the Use of Plastic

Either way, with plastic-eating caterpillars and plastic-infused roads slowly making their appearance in contemporary society, it only looks good for the future of our eco-system.

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Europe’s Longest Bridge Spans Troubled Waters

The Crimea Bridge under construction. The road bridge (right side in the picture) is now completed and ready for light traffic, while the rail bridge is scheduled for completion in 2019. Most of the spans are less than 200 meters, which a critic believes are insufficient to let ice that breaks up in spring pass safely underneath. (Image courtesy of the official information site for the construction of the Crimea Bridge.)

Earlier this month, Russian President Vladimir Putin got behind the wheel of a bright orange dump truck and led a convoy across the Crimea Bridge, a new bridge that links Russia to the Crimean Peninsula. The bridge, which stretches12 miles across the Kerch Strait, is now Europe’s longest bridge.

But media coverage of the bridge hasn’t focused on its length, or any of its physical properties. That’s because the new bridge connects Russia to territory it annexed from the Ukraine in 2014—an action Western governments have called illegal. To many observers, especially those in the Ukraine, the bridge was a political power move, designed to seal Russia’s hold on the region.

While the politics of the bridge are complicated, its engineering is fascinating. A bridge across the Kerch Strait has been under consideration for more than a century, but has been blocked by brutal geological and environmental conditions. Experts in the area aren’t sure how long the bridge will stand.

History

The first Russian plans for the bridge were put forward by Tsar Nicholas II in 1903, but were then sidelined by wars and economic concerns soon afterward. German engineer Albert Speer picked up the idea for the bridge in 1943, envisioning that it would aid in the Nazi takeover of Soviet Russia. Bridge construction started that year, but was halted by Soviet attacks, and much of the remaining bridge was blown up by the German army during its retreat from the region.

The next year, the Soviet Army used the leftover building materials to build a single-track railway bridge across the strait for the wartime Yalta Conference. Part of the conference delegation managed to take the train across the bridge, but seasonal ice floes took out several of the structure’s supports in early 1945, and the bridge was not repaired. More permanent plans were put on hold due to the cost of the project and the difficult building conditions across the strait.

After the Soviet Union collapsed, politics became yet another barrier to bridge building. In 1954, Soviet Russia had transferred control of the Crimean Peninsula to Soviet Ukraine, so Russia no longer had control of Crimea when the USSR disbanded. Proposed projects in the 1990s and 2000s collapsed, but in 2010, the two countries finally signed an agreement to build a bridge together.

But Russia’s annexation of Crimea in 2014 severely strained relations between the two countries. The Ukraine imposed sanctions on Crimea, effectively cutting off most of its trade and forcing it to conduct trade across the strait with Russia by ferry. These sanctions made goods expensive in Crimea, as well as limited the number of Russia tourists crossing the strait to vacation there. So, in 2015, Putin announced that Russia would build a bridge to the peninsula on its own.

Building Bridges

In early 2015, the Russian government awarded the 228billion-ruble ($3.7 billion) bridge contract to infrastructure construction firm Stroygazmontazh Ltd. (SGM), a company that specialized in pipelines but which had not previously built any major bridges. The risk of international sanctions made it difficult to attract foreign investment or obtain insurance to cover the project, and SGM eventually used a small Crimean insurance company to underwrite a potential $3 billion loss.

The physical environment also presented several barriers to bridge construction. The site’s historic significance briefly worked against the project: divers searching the sea floor in preparation for the construction found over 200 bombs and a downed WWII-era plane. The weather also posed problems in the early stages of the project. Leonid Ryzhenkin, the project’s construction director, told NPR in 2016 that poor weather had interfered with the work, making it impossible for construction vessels to leave port. To limit weather disruption, SGM put up three temporary bridges to transport workers, supplies and heavy machinery like mobile cranes and piling rigs to the build sites.

Despite these disruptions, the project was finished ahead of schedule. And while officials projected that the road portion of the bridge would be finished by the end of 2018, it’s already open to light traffic.

The finished road bridge has four lanes, with a two-lane railroad bridge planned for the end of 2019. It stretches from the town of Taman in Russia to the city of Kerch on the Crimean Peninsula, passing through Tuzla Island along the way. It covers 4 miles of open water between Taman and Tuzla, 4 miles across the sandy island, and 3.4 more miles of water from Tuzla to Crimea.

Composite satellite image of the completed bridge, stretching from the Crimean Peninsula (left) to Russia’s Taman Peninsula (right). Approximately one-third of the bridge passes over Tuzla, an island that legally belongs to Crimea (Image courtesy of Google Maps.)

Between Tuzla and Crimea, there is a 745-foot double shipping channel arch, with one arch on the road bridge and one on the forthcoming rail bridge. Both arches have a 115-foot clearance for boats to pass underneath. The arches were built on land and towed out to sea by boat.

The road bridge is completed, and the rail bridge is on track to be finished soon. International disapproval hasn’t stopped the project’s construction—or even slowed it. But while the political and economic challenges facing the bridge have largely been overcome, there are other possible threats lurking under the waterline.

Shaky Ground

The Kerch Strait is known to be geologically unstable. A tectonic fault passes through the ocean floor under the strait, and the bedrock is covered in a layer of silt up to 197 feet thick that must be dug through to get a stable foundation. Further complicating matters is that the strait’s seismic activity can make mud volcanoes from the silt. Mud volcanoes are formed when water heated deep in the Earth’s crust mixes with underground mineral deposits, and the mixture is forced upward through a geological fault. As of 2010, Ukraine’s Department of Marine Geology and Sedimentary Ore Formation reported almost 70 mud volcanoes found in the Azov-Black Sea Basin where the Kerch Strait is located.

The bridge is supported by over 7,000 piles of three different varieties: bored piles (reinforced concrete piles poured into depressions on-site), prismatic piles (blunt, wedge-shaped supports), and tubular steel piles. These piles were driven up to 300 feet below water level because of concerns about stability.

The site’s tubular pillars are arranged in a fan shape, with many of the supports set at an angle, making the bridge more stable in case of seismic activity.

But not everyone thinks these measures will be enough to keep the bridge steady on its perilous ground. Civil engineer Georgy Rosnovsky, who previously designed two other possible versions of the Kerch Bridge, is troubled by the current design. He believes that the bridge is necessary, but has stated that he thinks it’s being built “in the wrong place and the wrong way.” He believes the pilings need to be at least 100 meters (328 feet) long, and worries that they are not sunk deep enough into the bedrock to be stable.

Rosnovsky also thinks that the bridge’s spans (the distance between supports) aren’t long to allow ice floes through. He planned his 1993 bridge with spans of 230-660 meters (755-2,170 feet), but said that any spans over 200 meters would be safe from ice. The current design’s longest span is 227 meters, but most of the spans are much shorter than that. According to Rosnovsky, this design puts the bridge at risk of suffering the same fate as the temporary bridge that was destroyed by ice floes in 1945.

Yuri Medovar, of the Russian Academy of Sciences, is another critic of the bridge. Talking to news agency Sotavision in late 2016, Medovar expressed concern that the area hadn’t been sufficiently mapped, and that the complex geology and weather conditions would make the structure risky. He warned of the costs of poorly built bridges, citing the 2013 bridge collapse in Borisoglebsk that killed two people. “You can build everything, ” he concluded, “but how much it will cost, and how [long will it] stand?”

Despite the difficult building conditions, the bridge’s creators aren’t worried about the possibility of collapse. “It will stay intact for 100 years, Rotenberg said in an interview with the Itogi Nedeli weekly news roundup after the bridge’s inaugural drive. “At least. We guarantee that. Everything is done perfectly well.” But critics like Rosenberg aren’t satisfied. “It’s a rich firm, but it’s not built by experts. They think that money is everything,” Rosnovsky told FOCUS in 2016. “The bridges are built from the calculation of the service life of a hundred years, but I think that this bridge will be short-lived.”

Source : www.engineering.com

World’s Biggest Infrastructure Project is One You Never Heard Of

While the U.S. dawdles with much needed domestic infrastructure upgrades, China is already engaged in a project so massive that it will tilt the Earth in its favor. The trillion-dollar Belt Road Initiative (BRI) is a plan for a web of transportation routes (road, rail, shipping lanes, more—all leading to China) that will be created or expanded over the next 30-plus years. The BRI’s main purpose is to facilitate trade. China, the world’s leading producer of exports, no longer wants to rely on slow moving boats to move its goods out.

All roads lead to China. This map details major stops along the “New Silk Road,” the popular name for China’s Belt Road Initiative, an infrastructure project without equal. The map includes roads, rail and sea lanes. The routes are meant to ease the transport of goods produced in China. The dotted lines are simplifications of multiple parallel routes (Image courtesy of NPR.)

Lost in Translation

BRI not ringing any bells? This development plan for a number of megaprojects was introduced in 2013 as the One Belt One Road (OBOR). The “belt” referred to the roads, and “road,” inexplicably, the sea lanes. It was renamed the Belt and Road Initiative (BRI) at the 2017 Belt and Road Forum(BARF? Really, guys?) in Beijing.

The U.S.—and most of the West—paid scant attention. Even now, as money and concrete are pouring into projects, the U.S. continues to draw inward, led with an “America First” ideology. By the time the concrete is dry on the New Silk Road projects (China hopes to finish by 2049), the economic effect and, later, its political and even military consequences of the New Silk Road could make China the most dominant world super power for centuries to come.

Walls and Bridges

Under the Trump administration, the U.S. pulled out of the Paris Climate Accord in 2017 and then the Trans-Pacific Partnership. The proposed Mexico border wall extension will further separate the U.S. from neighbors to the South.

China’s state-run news agency responded with this during the Beijing conference, without any sense of irony: “As some Western countries move backwards by erecting ‘walls’, China is contriving to build bridges.” It was China that built the most famous wall of all time, the Great Wall, to keep out its neighbors to the North.

The New Silk Road will help China connect its far-flung provinces, but most of the development plans seem to be in neighboring countries with global trade partners. The BRI will help connect the heavily populated eastern part of the country with its Western provinces, which are considered underpopulated and underdeveloped. The highly promoted two thousand-kilometer Qinhai-Tibet railway, ostensibly built for tourism, deposits 3,000 Han Chinese (the predominant Chinese ethnic group) into Tibet, and has already made native Tibetans a minority in their own land.

While China has earmarked $900 billion to spend on the New Silk Road, the country is also prepared to loan $8 trillion to over 60 countries, many of them too poor to fund their own big infrastructure projects. One trillion dollars is said to have already been allocated by these countries. By comparison, the entire 47,000 miles of the US Interstate Highway system cost roughly half that amount ($459 billion).

Bugs Life Leads to Silk Roads

On its way to adulthood, the larvae of a certain insect, the Bombyx mori, gorge themselves on mulberry leaves and spin themselves into a cocoon so they can privately morph into an adult moth. One of these journeys was interrupted thousands of years ago, as Chinese legend has it, when a cocoon fell from a tree into a royal tea cup. A bored, but inquisitive, queen unraveled the cocoon into a one surprisingly long continuous fiber. The fiber could be spun into a thread which could produce the most luxuriant fabric. A silk industry was born.

Word of silk spread all the way to ancient Rome. Favored by Roman nobility, its trade became lucrative. Centuries of trade between Asia and Europe led to a tangle of trail and thoroughfares. Countless travelers, traders and pack animals demanded food, shelter and supplies. Marco Polo travelled along the Silk Road in the 13^th century. Towns and cities formed and grew. The Silk Road also spread wealth and facilitated cultural exchange.

The journeys along the Silk Road were not for the faint-hearted. They were plagued by bandits, extortionary rates of passage, ridiculous extremes in weather and imposing physical barriers. Some dangers were unseen. The camels carried fleas and introduced the bubonic plague to Europe.

The Silk Road name came much later, coined by German geographer Ferdinand von Richthofen in 1877 who was seeking a succinct term for the multitude of thoroughfares connecting Asia and Europe. Historians now favor the use of the more accurate “Silk Routes.”

Slow Boats to China

The Middle Ages led to ocean-going ships that took over from camel caravans over deserts and mountains. The Silk Road lapsed to serving local trade.

The modern maritime fleet relies on container ships for dry goods and tankers for liquids, both of which have reached gargantuan proportions. The biggest of all ships, a tanker, holds enough oil for 15,000 tanker trucks. Only a bit shorter, the biggest container ship carries 19,000 truck loads. Since China houses the world’s biggest labor force and produces the most goods, it makes sense that China also has the largest set of container ports to get those goods out, including the world’s biggest in Shanghai.

It’s not enough. The world’s growing appetites for goods demand that more of them arrive faster. Those ships could use more ports, and existing ports could be modernized. More ships could be built. For goods that are to be consumed and producers on the same landmass, why not connect them with modern highways and railroads? Why go around continents or through choke points (examples: the Suez and Panama canals) when you can make a relative beeline with a tractor trailer on a smooth multilane highway?

Maritime traffic dots China’s port cities. Ships squeezes through the Panama canals and Suez canals. (An interactive map, created by the data-visualization firm Kiln and University College London’s Energy Institute.)

Iron Will, Iron Road

Only China would seem to have the ability to even consider a project the magnitude of the New Silk Road. Upheavals caused by mega-projects are plagued by detractors in democracies. Transecting an unspoiled wilderness with pipelines or roads in the U.S. may be met with protest from environmentalists. Trying to move villages for a hydroelectric project will cause riots in India. In China, the national will overrides individual and special interests.

But joining the super initiative are 68 countries, all seeking benefits of trade passing through their borders—lands that time and technology may have forgotten can now hope to get into the act.

Not all countries are giving China a green light, however. Regional powers India and Japan (among others) have expressed reservations, each with a historical distrust of China’s international ambition.

What is Happening Right Now?

The New Silk Road is a big story told in billions of dollars.

In Sri Lanka (formerly Ceylon), the financially suffering Hambantota port was handed over to a Chinese company and has received almost $300 million out of a total of $1.1 billion for its revitalization. It has neighboring India a little nervous. A regional power, India has fought wars with Sri Lanka.

Routes connect China to the Arabian Sea through Pakistan, by passing a maritime route that took weeks to negotiate. Graphic by Marecelo Duhalde. (Image courtesy of SCMP.)

India’s prime minister has loudly objected to roadways cut through regions in dispute with Pakistan. Though these routes from China through Pakistan may not be officially part of the New Silk Road, they might as well be. Pakistan’s old roads will be improved, and new roads will be built. No small task, as the roads will snake over the tallest mountain range in the world with passes of over 5,000 meters. China has promised Pakistan $46 billion in energy and infrastructure—about 1/6 of Pakistan’s GDP. While the roads and rail will shortcut Chinese goods to Karachi and the Gwadar Port (half the cost of the much longer sea route), the coal power plant and hydro power stations planned will benefit the local economy for generations.

An estimated $300 billion has already been spent.

Eastward, Ho.

China’s Lhasa Express in the Tibetan grass lands near Lhasa.(Image courtesy of AP Photo/Color China Photo.)

Tibet, annexed by China in 1951, is known for the Dalai Lama (he used to live there), yaks—and one of the most inhospitable climates in the world. China sees it as a frontier to be settled, much the same way as the US thought of its West in the 1800s. Only 2 million Tibetans occupy an area that is somewhere in size between Texas and Alaska. There are 40 Chinese cities with more people than the entire Tibet Autonomous Region. To balance the population load, a railway was built.

It was a railway they said could never be built and qualifies as one of the modern world’s engineering marvels. Opened with great fanfare in 2006, China invited travel writers seeking the ultimate luxury rail adventure. It wasn’t a luxury. Complaints include not enough oxygen (oxygen masks drop from overhead and the highest elevation is 17,000 ft.) and the vomiting. But the pristine vistas and clear skies may be enticing enough for Chinese fleeing overcrowded cities, rampant pollution and limited opportunity. They may hope to tap into timber and mineral wealth. They will need places to live and an infrastructure to support them.

Building bridges: The Dashengguan Yangtze River Bridge under construction A section of the New Silk Road passes through Nanjing, capital of east China’s Jiangsu Province on its way to London. (Image courtesy of SCMP.)

Gassing up in Russia

China and Russia, “frenemies” through recent history, are acting on the opportunity provided by the void left behind by the U.S. in international relations. The China-Russian deal in 2014 has China buying 38 billion cubic meters of natural gas from Moscow for $400 billion. Parts of the New Silk Road are the pipelines that must be built to handle the flow of gas. In addition, plans call for road and rail to be newly constructed or improved (like the Trans Siberia Railway).

Chinese sources have the New Silk Road snaking through Poland and Germany, ending its western overland route by dropping off containers in London, after use of the existing Chunnel.

China’s trade with European nations is said to be a billion dollars a day and the E.U. trade with China is second only to the US—a situation that could easily switch to China’s favor with the completion of the New Silk Road.

Taking the high road: The Xinjiang-Tibet Highway, part of the New Silk Road, crosses the Tibetan Plateau. Elevation averages 4,500 meters., making it one of the highest roads for vehicles in the world. (Image courtesy of SCMP.)

Another country spurned by the U.S is being courted by China and included in New Silk Road projects: Iran. A New Silk Road corridor opened up in 2016 as a freight train completed a 10,000-km journey from Tehran, Iran to China.

Will it Work?

China has spent some of its 5,000 years of civilization in isolation. But since the emergence of a globalized economy, the choice has been either active participation or marginalization as the world passes by. Haltingly at first, Communist-led China has found advantage in participating in capitalist markets with its incredibly large human population. Cheap labor never seems to run out and workers work diligently for more hours per day and more days per week than in the West. Add to that the apparent disregard for costly safeguards Western nations have (arguably) put in place for protection of man and animal, of air and water, and the country has the formula for an engine to be able to make, grow or mine just about everything the rest of the world wears or uses. The New Silk Road is not only an expansion and improvement in the methods to get the goods out there at a faster rate, it creates a further dependence on China and increases its influence.

That’s if it all goes according to plan. China’s economy is deemed slow when GDP dips below 7 percent—when United States and European countries get than 2 percent growth. China’s population growth has been on a decline for decades, which will limit the labor force, if it hasn’t already. The aforementioned work conditions may also cause workers to ultimately throw a collective wrench in the engine. The smog over its cities gets thicker and the rivers have become more toxic; that will not be a cheap clean up, further slowing down the economy. China also has to play nice with others. Neighboring countries may see it as the big kid who has finally come out of his house to play but could steal their marbles. Building trust could be slow. China is also finding out that people in other countries are not as easy to control as its own. Parts of the New Silk Road stop abruptly at some countries’ borders, as their rulers fidget with more pressing issues.

Nevertheless, there is no mistaking such a huge investment will make a big difference when coupled with the force of a unified people and government and a massive investment.

Historians may one day see the New Silk Road as the catalyst for a new world order, with China on top. All without firing a shot.

Source : www.engineering.com