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Seismic Design of Reinforced Concrete Mat Foundations: NEHRP Seismic Design Technical Brief No. 7 An Overview

Ron Klemencic, P.E., S.E. FACI

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Soil pressure under centrally loaded foundation

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Bearing pressure distribution example (peak value shown in grey color)

USD v. ASD

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Seismic Demand Levels n  Direct Assessment using NLRHA n  Over-strength Factors n  Reduced, R

Ф = 0.6

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Examples of critical punching perimeter at shear walls

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Backstay effect on moment diagram

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WIDTH?

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Example of edge reinforcement at mat foundation edge

Example of placement diagram to clarify layering

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