Title:
Simple Rational Formulas for Cracking Torque and Twist of Reinforced Concrete Members
Author(s):
Chyuan-Hwan Jeng
Publication:
Structural Journal
Volume:
107
Issue:
2
Appears on pages(s):
189-198
Keywords:
cracking; design; reinforced concrete; torsion.
DOI:
10.14359/51663535
Date:
3/1/2010
Abstract:
To date, predictions of cracking torque have been empirical. A recently proposed rational model, the Softened Membrane Model for Torsion (SMMT), can predict the entire torque-twist curve, including the cracking point. In the SMMT, however, the cracking point has to be determined via a complicated iterative solution algorithm. This paper presents a step-by-step simplification of the SMMT and proposes a set of simple formulas for direct calculation of both cracking torque and twist. The formulas are validated with tests of 93 torsional specimens and compared with three other empirical formulas. It is shown that the proposed formulas are not only simple enough to be used for design purposes, but are also capable of producing more rational and accurate predictions than other empirical formulas.