全长黏结螺纹玻璃纤维增强聚合物抗浮锚杆蠕变试验研究

CREEP TESTING ON ANTI-FLOATING ANCHORS OF FULL-LENGTH BONDING THREAD GLASS FIBER REINFORCED POLYMER(GFRP)

通过4根全长黏结螺纹玻璃纤维增强聚合物(GFRP)抗浮锚杆在长期荷载作用下的拉拔蠕变试验,研究GFRP抗浮锚杆抗拔的蠕变力学模型,计算出模型中的蠕变参数并对模型的正确性进行验证。另外,引入时间损伤效应的概念,结合蠕变力学模型推导出GFRP抗浮锚杆的长期抗拔力。结果表明,中风化花岗岩中GFRP抗浮锚杆在40%的极限荷载下才发生蠕变,GFRP锚杆在低荷载水平下蠕变性能优良,能够满足工程需要;Burgers力学模型能够很好地描述GFRP抗浮锚杆的蠕变规律,模型预测结果与试验结果具有较好的吻合程度,且随着拉拔荷载的增大,模型中的各力学参数均逐渐减小;建立的蠕变损伤模型用于预测GFRP抗浮锚杆的长期抗拔力具有较好的适用性。

Based on four pull-out creep tests on anti-floating anchors of full-length bonding thread GFRP under the long-term loading,a creep model for the pulling resistant anchor was established,and the parameters of the model were derived and the correctness of the model was validated in this paper. In addition,the concepts of the time effect of damage were developed and the long-term pull-out strength of GFRP anti-floating anchor was obtained. The experimental results demonstrated that the creep behavior of GFRP anti-floating anchors in moderately weathered granite occurred when the load reached 40% of the load limit. The creep properties of GFRP anti-floating anchor were excellent under the low loading level,which met the engineering requirement. The Burgers model described well the creep behavior of the GFRP anti-floating anchors,and the predicted results were consistent with the experimental data. The mechanical parameters in the Burgers model were reduced gradually with the increase of the pulling load.