风化砂岩中压力型锚索锚固机理的拟静力分析

Pseudo-static force analysis of pressure-type cable anchoring mechanism in weathered sandstone

为更加精确地研究地震作用下风化砂岩中压力型锚索的锚固机理,根据集中力荷载作用在横观各向同性无限空间体内的应力解,结合拟静力简化方法推导出了圆形均布荷载作用下压力型锚索体系中锚索孔内砂浆体等效压应力解和锚固段砂浆与砂岩接触界面等效剪应力解,分析了砂岩弹性模量、泊松比、地震烈度、预应力荷载、承压板半径、锚索孔半径等因素对压力型锚索锚固效果的影响。研究结果表明:弹性模量、地震烈度、预应力荷载、承压板半径与等效应力分布曲线和应力峰值之间存在正相关关系;锚索孔半径与等效应力分布曲线和应力峰值之间存在负相关关系;砂岩泊松比与等效压应力分布曲线和压应力峰值之间存在正相关关系,但与等效剪应力分布曲线和剪应力峰值之间存在负相关关系。研究结果丰富了压力型锚索的锚固机理内容,可为实际工程加固边坡的抗震设计提供参考。

The stress solution of the concentrated force load in the transversely isotropic infinite space is applied.The anchoring mechanism of pressure type cable in weathered sandstone is studied under the earthquake more precisely.The equivalent compressive stress solution of mortar body in anchorage hole and the equivalent shear stress solution of the contact interface of mortar and sandstone in anchorage section under the circular uniform load in pressure type anchor cable system are derived based on pseudo-static method.The influence of the elastic modulus,the Poisson ratio,the seismic intensity,the prestress load,the radius of pressure plate and the radius of anchor hole on the anchorage effect of the pressure-type cable are analyzed.The results shows that there is a positive correlation between the elastic modulus,the seismic intensity,the prestress load,the radius of pressure plate and the equivalent stress distribution curve,the stress peak;there is a positive correlation between the radius of the pressure plate and the equivalent stress distribution curve,the peak stress;there is a negative correlation between the Poisson ratio of sandstone and the distribution curve of the equivalent compressive stress and the peak stress,but there is a negative correlation between the Poisson ratio of sandstone and the distribution curve of the equivalent shear stress and the peak shear stress.The results are enriched the content of anchorage type pressure mechanism,and are provided the reinforced slope seismic design for practical engineering applications.