CAJ | 학술논문

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.
위료유효지학정현비식항활장가고적점토변파지진영구위이,기우겁한분석상한정리,침대원호활동식토파파배모식,통과대설치항활장조건하토파진행외력공솔화내능모산솔적계산,안엄격역학정의추도출파체재지진작용하적안전계수,진이도출여안전계수상대응적변파지진굴복가속도계산공식,병결합 Newmark 활괴위이법대변파산생적전동가속도진행이차적분,추도출여변파설계안전계수밀절상관적파체지진영구위이적상세계산공식.이5.12문천지진와룡측참동향지진파위례,통과대일산례변파진행분석,급출료변파영구위이시정곡선이급불동설계안전계수여영구위이적관계,분석료산법여Ambraseys 산법적결과,험증료소제계산방법적유효성,병득도불동설계안전계수시변파토체점취력화내마찰각대파체영구위이적영향규률.연구결과표명,파체영구위이수착설계안전계수적증가축점정지수함수식감소변화,재교저설계안전계수하,파체영구위이수토체항전강도삼수영향교위민감,수착설계안전계수적제고,저충민감성칙축점강저.
@@@@In order to get the seismic permanent displacement of clay slope reinforced with cantilever stabilizing piles effectively, based on the upper bound theorem of limit analysis and circular failure mode of soil slope, factor of safety and the corresponding yield acceleration of slope with stabilizing piles under the earthquake can be derived through calculating the rate of work done by external loads and the energy dissipation rate. Then, combined with the Newmark’s sliding block method, the expression for the seismic permanent displacement related to design safety factor can be deducted by the double integrals of the rotational acceleration of slope. The paper takes a clay slope reinforced with cantilever stabilizing piles under the 5.12 Wenchuan Earthquake for example, the validity of the proposed method is verified by comparison with Ambraseys’s method. In Addition, the permanent displacement time history of the reinforced slope is given, and the relationship between the permanent displacement and factor of safety of the slope is also shown. The laws that the permanent displacement affected by the cohesion and internal friction angle of soil under different safety conditions are obtained. The research results show that the permanent displacement exponentially decreases with design safety factor of the slope increasing. In the case of lower design safety factor, the permanent displacement is more sensitive to soil shear strength parameters. However, the sensitivity is gradually reduced with the increase of the design safety factor.