Structural Analysis and Design at Base of Riser with Conduit Openings in Both Endwalls

摘要

This technical release (TR) discusses procedures for structural analysis and design of portions of risers at and near the wall-to-footing connection assuming openings in both endwalls framed by wall fittings with equal diameters. Applicable design criteria and structure specification are given in Technical Release No. 30, 'Structural Design of Standard Covered Risers'. See Report No. SCS/ENG/TR-30. The introduction of a significant opening in the upstream endwall near the top of the riser footing invalidates the conditions assumed in the design of the standard risers. This necessitates a re-evaluation of required concrete thickness and steel in the vicinity of the wall-to-footing connection. Deflection coefficients are provided from which the increased moment and shear values may be computed.