Solved Problems
1. Base Plate Bearing Area Without Confinement
A W10x49 steel column ( ksi) is supported by a concrete pier ( ksi). The pier dimensions exactly match the required base plate dimensions (). The column carries an LRFD factored axial load . Determine the minimum required area () for the base plate.
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0 of 1 Steps Completed2. Base Plate Bearing Area With Confinement
The same W10x49 column carrying is now supported by a massive concrete spread footing where the concrete support area is significantly larger than . Assume the maximum confinement multiplier applies. Determine the new minimum required area ().
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0 of 1 Steps Completed3. Base Plate Required Thickness
A base plate is sized at and to support a W10x49 column (, ). The factored load is . The plate is A36 steel (). Calculate the required plate thickness, .
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0 of 3 Steps Completed4. Anchor Rod Tensile Design
Determine the required LRFD nominal tensile strength () of an anchor rod. The factored uplift force on the column is . There are 4 anchor rods in the base plate layout, and the load is distributed equally among them. Assume the threads are included in the shear plane (though this is pure tension).
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0 of 2 Steps Completed5. Flange Force Extraction in Moment Connections
A fully welded moment connection is used to connect a W18x50 beam to a W14x90 column flange. The factored bending moment at the connection is . The depth of the beam is , and the flange thickness is . Calculate the required factored force () that the top flange weld must resist in tension.
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0 of 3 Steps CompletedCase Studies & Practical Considerations
Case Study 1: Large Base Plate Leveling
A contractor is setting a massive W14x311 column on a concrete foundation for a heavy industrial facility. The concrete foundation is rarely perfectly level, and the heavy base plate (3 inches thick) must be set to an exact elevation. How is this practically achieved?
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0 of 1 Steps CompletedCase Study 2: Resisting High Base Shear
A rigid frame building is designed to resist extreme lateral wind loads. The calculated lateral shear force at the base of the column exceeds the combined shear capacity of the anchor rods and the friction between the base plate and the grout.
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0 of 1 Steps CompletedCase Study 3: Overturning Moments & Prying Action
A tall slender column is subjected to a large lateral wind load, creating a significant overturning moment at the base plate in addition to its axial load.
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0 of 1 Steps Completed6. Base Plate Bearing Pressure Under Axial Load Plus Small Moment
A base plate (, ) is subjected to an axial load and a small overturning moment . Assume the eccentricity is small (). Calculate the maximum bearing pressure on the concrete.
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0 of 2 Steps Completed7. Moment Connection Simple Web Yielding Check
A moment connection transfers a flange tension force of into the column. The column is a W14x90 (, , ). The specified yield stress of the column is . Determine if the column web yields locally under this concentrated force. Assume the force is applied at a distance greater than the column depth from the column end.
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0 of 3 Steps Completed8. Anchor Rod Shear Capacity Calculation
Calculate the LRFD nominal shear strength () of a single 1-inch diameter ASTM F1554 Grade 36 anchor rod. The threads are included in the shear plane.
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0 of 3 Steps Completed9. Shear Lug Basic Bearing Capacity
A shear lug measuring 10 inches wide by 3 inches deep (embedded into the grout/concrete) is used to transfer a lateral shear force of . The foundation concrete has . Check if the bearing pressure on the concrete face of the lug is acceptable.
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0 of 4 Steps Completed10. Base Plate Bearing Pressure Under Axial Load Plus Large Moment
A base plate (, ) is subjected to an axial load and a large overturning moment . Assume the eccentricity is large (). Calculate the maximum bearing pressure on the concrete.
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0 of 3 Steps Completed11. Shear Transfer: Friction vs Shear Lugs
A column base must resist an axial load of and a lateral shear force of . The coefficient of friction between the steel base plate and concrete is . Determine if friction alone is sufficient, or if a shear lug is required.