基于SL 191的RAC梁开裂弯矩计算公式研究

Study on calculation formula for cracking moment of RAC beams based on SL 191

研究了再生混凝土(RAC)梁开裂弯矩的计算公式.首先分析了RAC梁开裂弯矩的影响因素,然后依据20组RAC梁的试验数据和《水工混凝土结构设计规范》(SL 191—2008)给出了RAC梁开裂弯矩的计算公式,最后对该公式进行了验证.结果表明:RAC梁的开裂弯矩比普通混凝土梁低,并随着再生骨料取代率的增加而不断降低;开裂弯矩修正系数与再生骨料取代率近似呈线性关系;本文给出的公式计算值与试验值吻合良好.

The formula for calculating cracking moment of recycled aggregate concrete(RAC)beams was studied.Firstly,the influencing factors of cracking moment of RAC beams were analyzed.Then,based on the test data of 20 groups of RAC beams and the Design Code for Hydraulic Concrete Structures(SL 191-2008),a formula for calculating cracking moment of RAC beams was proposed.Finally,the formula was verified.The results show that the cracking moment of RAC beams is lower than that of ordinary concrete beams,and it decreases with the increase of replacement rate of recycled aggregate.The correction coefficient of cracking moment is approximately linear with replacement rate of recycled aggregate.The calculated value of the formula in this paper is in good agreement with the experimental value.