岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2013年
10期
2154-2159
,共6页
土力学%挡土墙%地震%稳定性%拟动力法
土力學%擋土牆%地震%穩定性%擬動力法
토역학%당토장%지진%은정성%의동역법
soil mechanics%retaining wall%earthquake%stability%pseudo-dynamic method
基于拟动力法,考虑墙背面和填土面倾斜的工况,推导出挡土墙在地震作用下的抗倾覆稳定安全系数的计算表达式。数值算例结果表明,稳定安全系数随着填土内摩擦角、墙土外摩擦角和墙背面倾角的增大而增大,随地震放大系数、水平加速度影响系数和填土面倾角的增大而减小。其中,只有在地震作用较大时,放大系数的影响才逐渐显现,同时,摩擦角的影响却相对减弱;墙背面倾角和填土面倾角不同时,稳定系数随地震作用的变化趋势基本一致。通过对比2种计算方法的结果可知,拟动力法由于考虑了地震周期和地震波效应的影响,计算得到的稳定安全系数比拟静力法大。
基于擬動力法,攷慮牆揹麵和填土麵傾斜的工況,推導齣擋土牆在地震作用下的抗傾覆穩定安全繫數的計算錶達式。數值算例結果錶明,穩定安全繫數隨著填土內摩抆角、牆土外摩抆角和牆揹麵傾角的增大而增大,隨地震放大繫數、水平加速度影響繫數和填土麵傾角的增大而減小。其中,隻有在地震作用較大時,放大繫數的影響纔逐漸顯現,同時,摩抆角的影響卻相對減弱;牆揹麵傾角和填土麵傾角不同時,穩定繫數隨地震作用的變化趨勢基本一緻。通過對比2種計算方法的結果可知,擬動力法由于攷慮瞭地震週期和地震波效應的影響,計算得到的穩定安全繫數比擬靜力法大。
기우의동역법,고필장배면화전토면경사적공황,추도출당토장재지진작용하적항경복은정안전계수적계산표체식。수치산례결과표명,은정안전계수수착전토내마찰각、장토외마찰각화장배면경각적증대이증대,수지진방대계수、수평가속도영향계수화전토면경각적증대이감소。기중,지유재지진작용교대시,방대계수적영향재축점현현,동시,마찰각적영향각상대감약;장배면경각화전토면경각불동시,은정계수수지진작용적변화추세기본일치。통과대비2충계산방법적결과가지,의동역법유우고필료지진주기화지진파효응적영향,계산득도적은정안전계수비의정역법대。
Based on pseudo-dynamic method,a formula of stability safety factor of retaining wall against overturning under seismic action is derived,considering the inclination conditions of retaining wall back and backfill soil. Numerical results indicate that the stability safety factor increases with the increase of soil friction angle,wall friction angle and wall inclination angle;but it decreases with the increase of seismic amplification factor,horizontal seismic acceleration coefficient and backfill inclination angle. Thereinto,only under violent earthquake action,the seismic amplification effect can emerge gradually;at the same time,the influences of friction angles on the stability relatively weaken instead. The various trends of stability safety factors with seismic actions are in basic agreement under different wall inclination angles and backfill inclination angles. Comparing the calculating results by two methods,the overturning stability safety factor by pseudo-dynamic method considering the effects of earthquake period and seismic waves into account,is larger than that by pseudo-static method.