边坡稳定性分析例题.docx

1、边坡稳定性分析例题曲线滑动面的路基边坡稳定分析题目：某路堤高H=15m，路基宽b12m，填土为粘性土，内摩擦角，粘聚力，填土容重，荷载分布全路基（双车道），试验算路堤边坡稳定性。1.边坡稳定性分析原理1.1等代荷载土层厚度计算=4.09(N=2,Q=550KN,B=12M,L=12.8M,r=17.5KN/M3)1.2圆心辅助线的确定（4.5H法）1) 4.5H得E点E2)由得F点-查表得1=26度，2=35度1.3假设滑动圆弧位置，求圆心位置一般假设圆弧一端经过坡脚点，另一端经过的位置为：路基顶面左边缘、左1/4、中1/2、右1/4、右边缘等处，圆心分别对应O1，O2，O3，O4，O5，分别

2、计算这五种滑动面的稳定安全系数，从中找出最小值。1.4对滑动土体进行条分-从滑动面顶端（路基上）向左每5m划分一个土条。1.5在AUTOCAD图中量取各计算数据量取半径各土条的面积各土条横距图-圆心在O1图-圆心在O2图-圆心在O3图-圆心在O4图-圆心在O51.6数据填入EXCEL表格并计算五种滑动面的计算数据汇总圆弧法边坡稳定性分析表-O1分段XisinAicosAiSiGi=Si*rNi=GicosAiTi=GisinAiL126.750.7312310.682136.6224115.89279.053374884.74384731.406222.070.6033020.7975113.

3、1051229.339182.900962138.3608673317.1250.4681320.8836617.457305.498269.955499143.0131154413.0130.355710.934615.8602277.554259.40044898.728682859.87480.2699360.962888.4375147.656142.17499339.8577425464.13160.1129410.99360.53059.283759.224349971.04851406478合计942.709627505.7527691R=36.582Xa=3.1353Xb=29

4、.635K=1.99506211圆弧法边坡稳定性分析表-O2分段XisinAicosAiSiGi=Si*rNi=GicosAiTi=GisinAiL126.0690.7914420.6112416.1607282.812172.867321223.829529334.673220.7370.6295810.7769325.4912446.096346.587551280.8535396315.2770.46380.8859425.6378448.662397.487072208.0893293410.250.3111870.9503526.2598459.547436.729458143.00

5、4777855.41220.1643140.9864118.0611316.069311.77324951.9346894661.14860.0348710.999395.8908103.089103.0263023.59486507778合计1768.47095911.3067305R=32.938Xa=-1.842Xb=27.658K=1.54501031圆弧法边坡稳定性分析表-O3分段XisinAicosAiSiGi=Si*rNi=GicosAiTi=GisinAiL123.8690.7806020.6250320.0794351.39219.62848274.295299638.238

6、219.1660.6267830.7791938.8931680.629530.342059426.6069338314.3630.4697140.8828238.5938675.392596.24831317.240652349.12630.2984580.9544235.7511625.644597.129171186.728359454.6350.1515790.9884529.8233521.908515.87721679.110033336-3.304-0.108060.9941416.8884295.547293.816367-31.93699937-4.202-0.13740.9

7、90522.306840.36939.9861159-5.5467736338合计2793.027721246.497506R=30.578Xa=-5.86Xb=26.64K=1.51882406圆弧法边坡稳定性分析表-O4分段XisinAicosAiSiGi=Si*rNi=GicosAiTi=GisinAiL123.0590.7927220.6095822.329390.758238.199448309.761919342.124219.3870.6664780.7455349.3117862.955643.354395575.140003314.0010.4813140.8765553.4

8、268934.969819.545349450.013835948.8050.3026930.9530947.417829.798790.87019251.173711954.16350.143130.989742.6951747.164739.471348106.94176666-3.294-0.113220.9935730.1196527.093523.703649-59.678461397-5.64-0.193870.9810312.5422219.489215.323994-42.55325388-8.936-0.307180.951650.11261.97051.87522758-0

9、.605303047合计3972.34361590.194219R=29.089Xa=-9.269Xb=26.232K=1.53906982圆弧法边坡稳定性分析表-O5分段XisinAicosAiSiGi=Si*rNi=GicosAiTi=GisinAiL123.0720.8171990.5763625.1032439.306253.196238359.000594346.352218.5660.6576240.7533555.0529963.426725.793355633.5717651313.7380.4865860.8736368.72331202.661050.68089585.19

10、6824948.79120.3113870.9502863.54021111.951056.67075346.247772453.77650.1337650.9910154.5968955.444946.857533127.80473026-1.122-0.039750.9992145.1172789.551788.926914-31.386388957-5.961-0.211140.9774527.4401480.202469.375592-101.39168668-6.182-0.218970.975736.1231107.154104.553828-23.46338156合计5396.05511895.58023R=28.232Xa=-12.26Xb=26.235K=1.639177393.计算结果分析与结论3.1计算结果分析稳定系数K与滑动面位置变化示意图。重点说明：稳定系数在滑动面在路基最左端时最大,然后逐渐减小,当滑动面在路基中间时达到最小,为1.51,然后当滑动面在路基上的点继续向右移动时,稳定系数又逐渐增大，到达最右端时为1.64。3.2结论1)由于Kmin=1.51,大于规范规定的1.201.25,故边坡稳定。2)不满足要求,如何处理:1.减小边坡坡度2.换添路基土 ,选择粘性系数较大的土3.加固边坡