钢纤维混凝土桥墩抗震性能数值模拟与试验对比

Comparative analysis of Numerical and Experimental Results on Seismic Performance of Bridge Piers with Application of Steel Fiber Reinforced Concrete

摘要:

根据普通混凝土和钢纤维混凝土桥墩试件在低周反复荷载作用下的拟静力试验，基于纤维模型的有限元分析技术，采用考虑钢纤维影响的混凝土材料模型和考虑黏结－滑移效应的钢筋材料模型，建立了在反复荷载作用下普通混凝土和钢纤维增强混凝土桥墩的非线性有限元模型。采用数值分析方法得到钢纤维体积分数、配箍率和钢纤维混凝土区高度对钢纤维混凝土桥墩抗震能力的影响规律。对各试件模型的水平荷载－位移滞回曲线、骨架曲线和延性性能进行了分析，并与试验结果进行了对比。结果表明：数值模拟与拟静力试验结果基本一致，呈现出相似的规律性；钢纤维可部分代替箍筋的抗震作用，在一定范围内随着钢纤维体积含量的增加，桥墩试件的抗震性能增强；在桥墩局部采用钢纤维混凝土，可达到与整体采用钢纤维混凝土相近的抗震能力。

Abstract:

On the basis of the pseudo-static tests of reinforced concrete (RC) and steel fiber reinforced concrete (SFRC) pier specimens under low reversed cyclic loading, the nonlinear finite element models of concrete piers under cyclic loading were established using analytical method of fiber model. In the modeling, the concrete material model with the affect of steel fiber and steel material model considering bond-slip effect were adopted. The influences of steel fiber volume fraction, stirrup ratio and the height of SFRC region on seismic capacity of the piers were obtained by the numerical analysis. Several aspects about seismic performance of the models, including hysteretic characteristics, skeleton curves and ductility, were discussed by the numerical simulation method. The numerical results were compared with the test results. The results show that the simulation results of seismic response are basically identical with the pseudo-static test results; part of the stirrups’ role of seismic resistance can be substituted by the addition of steel fibers, and the seismic capacity of concrete piers is improved with the increase of steel fiber content in a certain range; similar seismic capacity can be sustained when the piers are constructed with local or wholly application of SFRC.