基于荷载传递法的嵌岩锚杆抗拔承载特性  

Anti-pullout bearing characteristics of rock-socketed anchor based on load transfer method

作　　者：雷勇[1] 尹君凡 陈秋南[1] 贺成斌[1] 

机构地区：[1]湖南科技大学岩土工程稳定控制与健康监测湖南省重点实验室,湖南湘潭411201

出　　处：《水利水电科技进展》2017年第4期70-76,共7页Advances in Science and Technology of Water Resources

基　　金：国家自然科学基金(51208195;41372303);岩土工程稳定控制与健康监测湖南省重点实验室开放基金(E21618)

摘　　要：为研究嵌岩锚杆抗拔过程中锚-岩界面承载特性,根据岩质地基中嵌岩锚杆的受力破坏机理,采用二段线性函数模拟锚杆-围岩界面的力学行为;基于荷载传递理论,推导了岩质地基中嵌岩锚杆的轴力、侧阻力及锚头位移的计算公式,分析了综合影响系数η对嵌岩锚杆抗拔承载特性的影响,给出了相应的确定方法;结合工程算例采用提出的计算方法对锚杆的轴力、侧阻力及P-S曲线进行了分析。分析结果表明:当上拔荷载较小时,嵌岩锚杆侧阻力呈双曲函数分布;当上拔荷载较大时出现塑性区,塑性区侧阻力均匀分布,弹性区呈双曲函数分布。In order to study the bearing characteristics of the interface between the anchor and rock in the anti-pullout process of a rock-socketed anchor,according to the failure mechanisms of the rock-socketed anchor in the rock foundation,the mechanical behavior of the interface between the anchor and surrounding rock was simulated using a two-segment linear function. The formulas of axial force,side resistance,and top vertical displacement of the rock-socketed anchor were derived based on the load transfer theory. The influence of the comprehensive influence coefficient η on the anti-pullout bearing characteristics of the rock-socketed anchor was analyzed,and the method for determining the value of η was provided. The axial force,side resistance,and P-S curve for an engineering example were analyzed using the presented calculation method. Results show that,when the uplift load is small,the side resistance of the rock-socketed anchor shows a hyperbolic distribution. When the uplift load is larger,the plastic zone appeares. The side resistance shows a uniform distribution in the plastic zone and a hyperbolic distribution in the elastic zone.

关 键 词：嵌岩锚杆 承载特性 荷载传递理论 综合影响系数 

分 类 号：TU476[建筑科学—结构工程]