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Punching Shear Strength Design of RC Slab According ACI318M-08 Spreadsheet

The main objective of this sheet is to evaluate the effect of design tje RC slab for punching shear strength . The increasing of the punching shear strength and deformation capacity when subjected to patch load was studied here.

An experimental study was carried out on reinforced concrete slabs under a central patch load with circular, square and rectangular shapes of patch areas. A single concrete mix design was used throughout the test program. All of slab specimens were reinforced with distributed mesh reinforcement with equal steel ratios in both directions.

The validation of the experimental work was made by analyzing the tested slabs by finite element method under cracking load. The results obtained by the finite element method were found to compare well with those obtained
experimentally. In order to calculate the ductility for the tested slabs, the punching load has been determined by applying the published failure criterion and a load-rotation relationship obtained from semi-empirical relationship for the tested slabs.

Conclusions on the influence of patch area on the punching shear capacity of reinforced concrete slabs were drawn. The experimental results confirm that the strength and deformation capacity are slightly influenced by the shape of the patch area. Among all specimens, the slabs with circular shape of patch area exhibited the best
performance in terms of ductility and splitting failure.

In flat-plate floors, slab-column connections are subjected to high shear stresses produced by the transfer of the internal forces between the columns and the slabs (ACI-421.1R-08, 2008; ACI-421.1-99, 1999). Normally it is desired to increase the slab thickness or using drop panels or column capitals of exceptionally high strength for shear in reinforced concrete slab around the supporting column. Occasionally, methods to increase punching shear resistance without modifying the slab thickness are often preferred (Cheng and Montesinos, 2010).

The ways to transfer the force from column to the slab need to be studied to increase the shear resistance. Several reinforcement alternatives for increasing punching shear resistance of slab-column connections, including bent-up bars (Hawkins et al., 1974; Islam and Park, 1976), closed stirrups (Islam and Park, 1976), shearheads (Corley and Hawkins, 1968), and shear studs (Dilger and Ghali, 1981), have been evaluated in the past five decades. But there is a little experimental and theoretical information about the influence of patch area or cross section area shape for supporting column in the reinforced concrete shear resistance.

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RC Element Analysis and Design Spreadsheet

The theory and techniques relative to the design and proportioning of concrete mixes, as well as the placing,
finishing, and curing of concrete, are outside the scope of this book and are adequately discussed in many other
publications . Field testing, quality control, and inspection are also adequately covered elsewhere. This is not to
imply that these are of less importance in overall concrete construction technology but only to reiterate that the objective of this book is to deal with the design and analysis of reinforced concrete members.

The design and construction of reinforced concrete buildings is controlled by the Building Code Requirements for
Structural Concrete (ACI 318-11) of the American Concrete Institute (ACI) [1]. The use of the term code in this text
refers to the ACI Code unless otherwise stipulated.

The code is revised, updated, and reissued on a 3-year cycle. The code itself has no legal status. It has been incorporated into the building codes of almost all states and municipalities throughout the United States, however. When so incorporated, it has official sanction, becomes a legal document, and is part of the law controlling reinforced concrete design and construction in a particular area.

Therefore, tensile reinforcement must be embedded in the concrete to overcome this deficiency. In the United States, this reinforcement is in the form of steel reinforcing bars or welded wire reinforcing composed of steel wire. In addition, reinforcing in the form of structural steel shapes, steel pipe, steel tubing, and high-strength steel tendons is
permitted by the ACI Code.

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Prestressed Post-Tensioned Concrete Section Spreadsheet

Prestress is defined as a method of applying pre-compression to control the stresses resulting due to external loads below the neutral axis of the beam tension developed due to external load which is more than the permissible limits of the plain concrete.

The pre-compression applied (may be axial or eccentric) will induce the compressive stress below the neutral axis or as a whole of the beam c/s. Resulting either no tension or compression.Prestressed concrete is basically concrete in which internal stresses of a suitable magnitude and distribution are introduced so that the stresses resulting from the external loads are counteracted to a desired degree.

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Development of Reinforcement Based on ACI 318-14 Spreadsheet

Development length is certain minimum length of the bar required on either side of a point of maximum steel stress, in order to transfer the bar force to surrounding concrete through bond, without slip,so as to prevent bar from pulling out under tension. This is “development length or anchorage length”. Hooks,bends, mechanical anchorages can be used to supplement.

End anchorage may be considered reliable if the bar is embedded into concrete a prescribed distance known as the “development length” of the bar. In a beam, if the actual extended length of the bar is equal or greater than this required development length, then no bond failure will occur.

If the actual available length is inadequate for full development, special anchorages ,such as hooks, must be provided to ensure adequate strength.

Methods for Determining the Development Length, ld
– The ACI allows the determination of the
development length by two methods:
• Tabular criteria (ACI Section 12.2.2).
• General equation (ACI Section 12.2.3).
– In either case, ld shall not be less than 12 in.
– The general equation of the ACI Code offers a simple approach that allows the user to see the effect of all variables controlling the development length.

A reduction in the development length ld is permitted where reinforcement is in excess of that required by analysis (except where anchorage or development for fy is specifically required or where the design includes provisions for seismic considerations).

The method for determining the development length in compression ld involves finding the the basic development length ldb and multiplying it by applicable modification factors.

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Steel Beam Design Excel Sheet with Gravity Loading

The Steel Beam module does not permit biaxial loading at the present time, so there are two potential approaches to this loading scheme:

One option is to do two separate Steel Beam runs. One run would apply the gravity loads to the beam with the beam oriented “web vertical”. The other run would apply the wind loads to the beam with the beam oriented “web horizontal”. This would require that the user manually combine the results of the two runs using engineering judgment to come up with a final result.

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Combined Tension and Shear in a Slip Critical Connection Spreadsheet

Combined tension and shear in a slip critical connection must be considered when bolted connections subjected to both shear and tension must be checked for prying action, the interaction between tension and shear must be considered.

The AISC Specification for Structural Steel Buildings (AISC, 2010) presents interaction equations for bearing connections and for slip-critical connections. However, little guidance for applying these equations to prying action analysis has been available.

This spreadsheet will demonstrate how these interaction equations may be used in the prying action analysis presented in the 14th edition Steel Construction Manual (AISC, 2011) by comparing two methods. The Excel sheet is formulated in terms of Load and Resistance Factor Design (LRFD), but the principles are similar for Allowable Strength Design (ASD).

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Concrete Pool Design Spreadsheet Based on ACI 318-14

Concrete pool design for rebar at middle or equal of each face, is pool wall at inward soil pressure before restrained at top and pool filled. since the wall axial load small and sections under tension-controlled (aci 318-14 21.2.2), only check wall flexural capacities are adequate. since the slab at flexural & axial loads, the combined capacity of flexural & axial must be checked.

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Wind Analysis for Shade Open Structure Spreadsheet Based on ASCE 7-16

In order for a structure to be sound and secure, the foundation, roof, and walls must be strong and wind-resistant. When building a structure it is important to calculate wind load to ensure that the structure can withstand high winds, especially if the building is located in an area known for inclement weather.

The main wind force resisting system of a building is a vital component. While wind load calculations can be difficult to figure out because the wind is unpredictable, some standard calculations can give you a good idea of what a building can withstand. Wind loading analysis is an essential part of the building process.

If wind loading analysis is not done correctly the resulting effects could include collapsed windows and doors, ripped off roofing, and more. Contact Buildings Guide for quotes on safe and durable prefabricated steel buildings.

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Concrete Pier (Isolated Deep Foundation) Design Spreadsheet Based on ACI 318-14

Foundation elements are most commonly constructed of reinforced concrete. As compared to the design of concrete elements that form the superstructure of a building, additional consideration must be given to concrete foundation elements due to permanent exposure to potentially deleterious materials, less precise construction tolerances and even the possibility of unintentional mixing with soil.

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Reinforced Flat Slab Design Spreadsheet

Flat slab system is an important division of concrete floor system. A civil engineer must know all the aspects regarding the flat floor system. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place. These materials are originally located at different websites. A civil engineer should study these lectures and materials for structural engineering acumen.

A flat slab is a reinforced concrete slab supported directly by concrete columns without the

use of beams. The benefits of using flat slab construction are becoming increasingly recognized. Flat slabs without drops (thickened areas of slab around the columns to resist punching shear) can be built faster because formwork is simplified and minimized, and rapid turn-around can be achieved using a combination of early striking2 and flying systems. The overall speed of construction will then be limited by the rate at which vertical elements can be cast. Flat slab construction places no restrictions on the positioning of horizontal services and partitions and can minimize floor-to-floor heights when there is no requirement for a deep false ceiling. This can have knock-on benefits in terms of lower building height, reduced cladding costs and prefabricated services.

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