论文部分内容阅读
为了有效地确定悬臂式抗滑桩加固的黏土边坡地震永久位移,基于极限分析上限定理,针对圆弧滑动式土坡破坏模式,通过对设置抗滑桩条件下土坡进行外力功率和内能耗散率的计算,按严格力学定义推导出坡体在地震作用下的安全系数,进而导出与安全系数相对应的边坡地震屈服加速度计算公式,并结合Newmark滑块位移法对边坡产生的转动加速度进行二次积分,推导出与边坡设计安全系数密切相关的坡体地震永久位移的详细计算公式。以5.12汶川地震卧龙测站东向地震波为例,通过对一算例边坡进行分析,给出了边坡永久位移时程曲线以及不同设计安全系数与永久位移的关系,分析了算法与Ambraseys算法的结果,验证了所提计算方法的有效性,并得到不同设计安全系数时边坡土体黏聚力和内摩擦角对坡体永久位移的影响规律。研究结果表明,坡体永久位移随着设计安全系数的增加逐渐呈指数函数式减小变化,在较低设计安全系数下,坡体永久位移受土体抗剪强度参数影响较为敏感,随着设计安全系数的提高,这种敏感性则逐渐降低。
In order to effectively determine the permanent seismic displacement of clay slope reinforced by cantilever anti-slide piles, based on the upper bound theorem of limit analysis, aiming at the failure mode of circular sliding slope, the external force and internal energy According to the strict mechanics definition, the safety coefficient of the slope under earthquake action is deduced, and then the formulas for calculating the yielding acceleration of the slope earthquake corresponding to the safety factor are deduced. Combined with the Newmark slider displacement method, The second integral of rotational acceleration is deduced, and the detailed formula of permanent displacement of slope earthquake is deduced which is closely related to slope design safety factor. Taking the eastward seismic wave of the Wolong station in 5.12 Wenchuan earthquake as an example, the relationship between the permanent displacement time history curve and the safety factor of different designs and the permanent displacement is given through an example slope analysis. The relationship between the algorithm and the Ambraseys algorithm The validity of the proposed method is validated and the influence of soil cohesion and internal friction angle on the permanent displacement of slope is obtained when the design safety factor is obtained. The results show that the permanent displacement of the slope gradually decreases exponentially with the increase of the design safety factor. Under the low design safety factor, the permanent displacement of the slope is sensitive to the shear strength parameters of the soil. With the design The safety factor increases, this sensitivity is gradually reduced.