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Stress In a Plate Due To a Point Load Spreadsheet

Purpose of calculation: Calculate plate bending stress when subject to a point load.
Calculation Reference: First principles

Calculation Reference
Peterson’s Stress Concentration

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Design Of Spread Footing As Per ACI 318-07 Spreadsheet

PIPE SUPPORT FOUNDATION
DESIGN OF SPREAD FOOTING TO ACI 318-07
DESIGN OF ISOLATED FOOTING
Density Of Concrete
Density Of Soil
Depth Of Foundation
Soil Bearing Capacity
Length Of Footing
Width Of Footing
Thickness of Fdtn.
Width Of Pedestal
Length Of Pedestal
Height Of Pedestal
Coefficient Of Friction
Ground Water Table Ht.

1.0 Load Calculation for Footing & Soil:
Self Wt. Of Footing
Weight of Soil
Self Wt. Of Pedestal
Weight of Footing + Soil

2.0 Check Maximum and Minimum Pressure at Footing Base:
Area of Footing
Section Modulus
Section Modulus
Total Vertical Load

3.0 Check for Overturning:
Overturning Moment
Due to External Load
Due to wt. of Pedestal
Due to Self Wt. of Fdn
Due to Wt. of Soil
Total Stabilizing Moment
F.O.S. against Overturning

4.0 Check for Sliding:
Resultant Shear Force
Total Vertical Load
F.O.S. against Sliding

5.0 Load Case Check:
Check Max. & Mini. Pressure at Footing Base:

6.0 Check for Overturning & Sliding:

7.0 Check For Shear
a) Two Way Shear
b) One Way Shear

8.0 Design Of Foundation/Footing:
a) Calculation of Reinforcement at Bottom
b) Calculation of Reinforcement at Top

This presents the design of isolated spread footing using the results from Staad Support Reactions.

Calculation Reference
Reinforced Concrete Footings

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Moment Connection Of Portal Frame Spreadsheet (Eurocode 3)

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Design Of Ships Masts Spreadsheet

This spreadsheet incorporates Vessel motion loading with Environmental Criteria in estimating stresses for mast designs. It covers both unstayed and stayed mast in SI unit and Imperia unit. Although it is being specifically doctored for mast, it could be adapted for estimating stresses of similar structures on floating unit such include Burner boom, Derricks etc. The calculation is referenced to Design of Ships masts R.W. Milliman published by the Association of Engineering and Shipbuilding Draughtsman AESA.

Calculation Reference
Design of Ships Masts

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Tubular Joints in Offshore Structures As Per API RP2A (WSD) Spreadsheet

This spreadsheet defines the principle terms and ratios used in tubular joint design. It presents the classifications for T, Y, X, N, K and KT joints and the details of joint arrangements. It describes design methods for static strength.

The main structure of a topside consists of either an integrated deck or a module support frame and modules. Commonly tubular lattice frames are present, however a significant amount of rolled and built up sections are also used. This calculation sheet refers to the design of tubular joints. These are used extensively offshore, particularly for jacket structures.

Only static check is performed here, fatigue check shall be added in further revisions.

Calculation Reference
Tubular Steel Construction

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Design Of Monorail In Offshore Industry Spreadsheet

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Design Of Concentrically Loaded Isolated Footing Spreadsheet

The footings were proportioned so that the bearing pressure does not exceed the safe bearing capacity of the soil. The bending moments and shears are determined at critical sections. The calculation follows methods set out in ACI 318-08.

Calculation Reference
Reinforced Concrete Design

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Angle Type Tension Fitting Calculation Spreadsheet

Purpose of calculation: Calculate stress in a ‘angle’ tension fitting.
Calculation Reference: UK railway industry method (the British Rail “Brown Book” method).
Note: requires XlXtrFun addin (interp function).
Calculation Validation: Independent verification is required.

Calculation Reference
Peterson’s Stress Concentration

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Angle Section Properties Calculation Spreadsheet

If you are like me you may have found out the hard way that the values published in the 13th Edition AISC manual for the principle axis section modulus for angles are incorrect. Although the values for principle axes moment of inertia are correct, an incorrect value of “c” was consistently used to obtain the section modulus. In addition to the principle axis properties and orientation of the principle axes with respect to the geometric axes, Version 2.0 now includes the following:

1. The ability to specify orientation of the angle legs and to subsequently calculate the section properties about the modified axis orientation. The following are addressed SLVD Unequal leg – short leg vertically SLVU Unequal leg – short leg vertically up LLVD Unequal leg-long leg vertically down LLVU Unequal leg – long leg vertically up EQVLD Equal leg – long leg vertical down EQVLU Equal leg – long leg vertically up

2. Calculation of the Beta w factor which is utilized in the 13th Edition AISC Manual – equation F10-6 for calculation of allowable moments about the major principle axis for unequal length angles. The proper sign of Beta w is also calculated which is dependent upon whether the shear center is in flexural compression or tension.

3. Calculation of the torsional resistance factor J

4. Calculation of the extreme fiber distances from neutral axis to all angle tip points. The worksheet is protected but without a password

Calculation Reference
AISC 13th Edition

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Flexible Seat Angle Reaction Analysis Spreadsheet

This spreadsheet is a program written in MS-Excel for the purpose of determining the capacity of a flexible seat angle connection and determine the allowable beam end reaction, the allowable end moment for the purpose of end connection design and the weld capacity of the angle to a steel connection.

Design References:

1. AISC Steel Construction Manual, 13th Ed.
2. AISC spreadsheet, “AISC_ShapesDatabase_v13.0-Current.xls”
3. Handbook of Structural Steel Connection Design and Details; Tamboli, Akbar R.; The McGraw-Hill Companies, Inc.; 1999

This program is a workbook consisting of two (2) worksheets, described as follows:

Doc – documentation sheet
ANGLEFLEXSEAT – Allowable End Reaction for Angle Seat Connection Design

1. Revision 1.2 (5/31/10) Limited the angle width, ‘b’, to prevent erroneous output and limit angle bending stress.

Program Assumptions and Limitations:

1. This program uses the database of member dimensions and section properties from the “AISC Shapes Database”, Version 13.0 (2005) as well as the AISC 13th Edition (ASD) Manual (2005).

2. The user may select a beam from W, S, M, C, and MC shapes and angles from all AISC listed shapes.

3. This program determines the appropriate minimum angle thickness from design procedures of the Handbook of Stuctural Steel Connection Design and Detail, p. 154-156.

4. This program utilizes the procedure which a steel fabricator would typically use to determine end connection design loads when end reaction values are not specified on the design and construction drawings by the engineer. This procedure is based on the AISC 13th Edition (ASD) Manual (2005) Maximum Total Uniform Load Tables on pages 3-33 to 3-95 and AISC Specification Chapter J10, pages 16.1-116 and 16.1-117.

5. The welding capacity, found in this program, is from the AISC 13th Edition (ASD) Manual (2005) Coefficients C for Eccentrically Loaded Weld Groups (Table 8-4) and AISC Specificiations Chapter J2, pages 16.1-93 to 16.1-102.

6. This program does not check the column or angle supporting member’s web or flange as there are too many variables for connection.

7. This program contains “comment boxes” which contain a wide variety of information including explanations of input or output items, equations used, data tables, etc. (Note: presence of a “comment box” is denoted by a “red triangle” in the upper right-hand corner of a cell. Merely move the mouse pointer to the desired cell to view the contents of that particular “comment box”.)

Calculation Reference
AISC Steel Construction Manual, 13th Ed.

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