桩端后注浆灌注桩竖向承载性能的数值分析

采用数值方法建立了桩端后注浆灌注桩桩土体系分析模型,并对某工程注浆前后的钻孔灌注桩的承载性能进行了数值模拟,结果计算值与实测值较吻合,验证了该方法的有效性.按照该模型模拟单桩静载试验,对均质土层中的后注浆钻孔灌注桩的承载性能进行了模拟分析,结果表明:注浆量以及注浆体强度对承载力的影响存在一定范围;桩长的变化也影响注浆量对承载力的贡献;桩侧翻浆高度以及桩侧摩阻力提高对承载力影响显著;承载力随着桩侧翻浆高度和侧摩阻力的提高而线性增加.

Numerical Analysis on the Bearing Capacity of Post-grouting Bored Pile under Vertical Load

An analysis model of post-grouting bored pile and soil was built up by numerical method to simulate the bearing capacity of the pile.The results of numerical analysis on the pile load tests are agreement with the measured ones.The effects of post-grouting on bearing capacity were simulated by this method with considering the grouting volume,the strength of grouted soil body,the height of turn-up grout and the improvement of skin friction.The results show that the grouting volume and the strength of grouting soil body have a limited effect on the bearing capacity,and the increasing effect of the grouting volume is also influenced by the length of pile.The height of turn-up grout and the improvement of skin friction have a great effect on the bearing capacity,which is linearly increased with the increasing of the height of turn-up grout and the improvement of lateral friction.