抗滑桩设计岩土工程课程设计(共13页)

1、精选优质文档-倾情为你奉上2013年岩土工程课程设计某高速公路 K15+620K15+880 滑坡处治设计 设 计： 秦万家 学 号： 班 级：10级土木12班 指导教师： 邓荣贵 2013年11月1、工程概况1.1：概述某高速公路K15+620K15+880位于崩坡积块石土斜坡前缘，原设计为路堑墙支挡块石土，泥岩已护面墙防护。开挖揭露地质情况与设计差异较大，在坡题前缘全断面开挖临空后，受预计暴雨作用块石土形成牵引式滑坡。滑坡发生后，对该滑坡进行施工图勘测，并结合工程地质勘测报告，对该滑坡提出处置的方案。K15+620K15+880滑坡采用“清方+支档+截排水”综合处理，滑坡处治平面布置图见附

2、图1，要求对抗滑桩进行设计。1.2：工程地质条件 该高速公路 K15+620K15+880 滑坡区位于条状低山斜坡中上部，沿该段公路左侧展布，前缘高程304m 左右，后缘高程355m 左右，地形坡角约30 度。滑体纵向长约105 米，宽200300 米，滑体厚度820 米，面积接近1.5×104m2，体积约15×104m3。主滑动方向202°，属于大型牵引式块石土滑坡。 通过地质测绘及钻探揭露，滑体物质主要由崩坡积块石土（Q4c+dl）组成。块石土呈紫红、灰褐等色，稍湿湿，松散稍密，成份主要为砂岩、少量粉砂质泥岩，多为中等风化，棱角状，粒径20cm50cm，约占6

3、0%，次为小块石，约占10%，其间由紫红色低液限粘土充填。在滑体后部相对较薄，厚m；在滑体中部、前端分布较厚，厚924m。滑动带（面）多为块石土与基岩的接触带，滑带厚0.20.6m 左右，滑带土中小块石含量较低（<5）,低液限粘土湿、 可塑软塑，有搓揉现象，见镜面、擦痕等。滑床物质主要为侏罗系沙溪庙组泥岩、砂岩。泥岩多为紫红色，主要由粘土矿物组成，砂质含量不均，局部富集，泥质结构、厚层状构造；砂岩多为灰白色，主要由长石、石英、云母等矿物组成，泥、钙质胶结，细粒结构，厚层状构造。岩层产状265º290º15º28º,基岩顶面的产状近似于岩层产状。岩体

4、内见节理、裂隙发育，裂隙产状273º72º、210º65º。 该滑坡的变形迹象明显，包括拉张裂缝、滑塌、地裂缝等。拉张裂缝主要沿后缘基岩陡壁的壁脚分布，分布高程一般在340350m 左右，缝宽一般1020cm，长度一般615m，一般无下错，可见深度30cm，延伸方向100º左右。随着滑坡变形发展，该滑坡可分为I、II 级。I 级滑坡主要位于路线左侧的第一级块石堆积坡体，为滑坡的主要推力来源。该段滑体深厚，下滑变形强烈，裂缝密集，前缘溜塌、鼓出明显。II 级滑坡位于整个滑坡的右后缘块石堆积坡体上，滑体厚度较小，变形不强烈，主要受一级牵引所致。 1

5、.3平面图及主要计算断面：见附图。 1.4主要计算参数与数据根据地勘单位提供的室内试验值、推荐值，结合实测断面反算参数，确定计算参数及数据如下： 设计采用滑面参数 C=20kPa =10o。=22.5kN/m3滑坡稳定安全系数 K=1.202、 设计计算2.1滑坡推力计算*传递系数法第i条块的剩余下滑力（即该部分的滑坡推力）Ei可用下式计算式中Ei第i块滑体剩余下滑力；Ei-1第（i-1）块滑体剩余下滑力；Wi第i块滑体的重量；Ri第i块滑体滑床反力；传递系数，；ci第i块滑体滑面上岩土体的粘聚力；li第i块滑体的滑面长度；第i块滑体滑面上岩土的内摩擦角；第i块滑体滑面的倾角；第（i-1）块滑

6、体滑面的倾角。安全系数。计算时从上往下逐块进行。按上式计算得到的推力可以用来判断滑坡体的稳定性。如果最后一块的En为正值，说明滑坡体是不稳定的；如果计算过程中某一块的Ei 为负值或为零，则说明本块以上岩土体已能稳定，并且下一条块计算时按无上一条块推力考虑。专心-专注-专业剖面1滑面1：条块号hb底滑面长（m）s重度(kN/m3)重量（kN/m3)倾角倾角/弧度C传递系数下滑力抗滑力剩余下滑力稳定性系数安全系数支护力1支护力200/0/14.959.9313.6424.5767522.5552.42.250.300.0371.496.-124.1.1.2-149.-50.210.3318.782

7、5.13143.479222.53228.28241.840.300.0.2029.1264.764.0.1.2916.1169.312.633.34.4337.88422.5852.3941.840.300.11332.267.1064.812330.1.21277.1331.416.068.7910.64126.0925522.52837.34.340.300.0.2656.846.1809.0.1.22171.2340.516.6711.3912.78186.3973522.54193.27.020.300.0.3699.1226.2473.0.1.22968.3213.613.9226

8、.2326.64401.1878522.59026.6.610.300.0.3357.2888.48292468.0.1.2562.1140.2062176.127.0326.89270.570322.56087.831753.650.300.0.855.2103.-1247.2.1.2-1497.-1076.8012.8812.9139.28422.5883.893.650.300.1-1191.574.-1766.-0.1.2-2119.-2004.剖面1滑面2：条块号hb底滑面长（m）s重度重量（kN/m3)倾角倾角/弧度C传递系数下滑力抗滑力剩余下滑力稳定性系数安全系数支护力支护力20

9、0/15.553.37.039.157522.5206.0437562.011.300.0181.231.-49.1.1.2-59.-13.210.338.7911.9869.792622.51570.333542.810.300.0.1020.600.419.0.1.2503.623.316.6711.3915.52153.76522.53459.712542.810.300.12770.1005.1765.0.1.22118.2319.413.8926.4226.64403.697622.59083.1966.610.300.0.2470.351872938.-468.1.1.2-562.

10、25.56.126.8326.89268.1658522.56033.3.650.300.0.-83.2081.-2165.-24.1.2-2598.-2181.6012.8812.9139.28422.5883.893.650.300.1-2108.574.-2683.-0.1.2-3220.-3105.37181剖面2：条块号hb底滑面长（m）s重度重量（kN/m3)倾角倾角/弧度C传递系数下滑力抗滑力剩余下滑力稳定性系数安全系数支护力支护力200/15.94.9789.8514.685122.5330.41475601.300.0286.330.-44.1.1.2-53.12.28.39

11、28.0330.66200.2743522.54506.240.300.0.1796.849981789.7.0.1.29.366.310.4223.6726.7222.6163522.55008.280.300.1.2359.1740.618.0.1.2741.1089.48.127.0528.7250.48322.55635.8675200.300.0.2539.730342004.534.0.1.2641.1042.510.5618.7819.44175.217422.53942.3915150.300.0.1553.1402.150.0.1.2180.461.6018.7619.439

12、9.052822.52228.688150.300.1727.1040.-313.1.1.2-375.-167.剖面3：条块号hb底滑面长（m）s重度重量（kN/m3)倾角倾角/弧度C传递系数下滑力抗滑力剩余下滑力稳定性系数安全系数支护力支护力200/16.193.989.3912.318122.5277.15725651.300.0251.306.-55.1.1.2-66.-5.27.415.398.7636.65222.5824.67470.300.0.550.378.171.0.1.2206.281.38.428.9632.68228.928822.55150.898280.300.0.

13、2580.1958.621.0.1.2745.1137.49.3416.6318.27147.508122.53318.93225240.300.0.1969.1201.768.0.1.2921.1162.2121458.828.2729.28256.408922.55769.20025150.300.0.2251.2088.163.0.1.2196.613.6032.9935.25145.15622.53266.01210.300.1.1333.1701.-368.1.1.2-442.-102.取三者平均值为支护力：F=1081KN/m。3、 抗滑桩计算： 当滑坡体为粘聚力较大的粘土、土夹石

14、、较完整的岩层时，滑体系均匀向下蠕动，或整体向下移动，推力可按矩形分布考虑。 拟采用2×3m的桩径，间距5m，桩长20m，嵌固深度10m，采用k值法计算。K=kN/m3 （该桩属于弹性桩）嵌固段任意深处内力计算： 用excel计算如下：受荷段A型桩总长20mz(m)Q(kN)M(kN.m)0000.5270.2567.56251540.5270.251.5810.75608.06252108110812.51351.251689.062531621.52432.253.51891.753310.56254216243244.52432.255472.562552702.56756.2

15、55.52972.758175.06256324397296.53513.2511418.062573783.513242.257.54053.7515201.562584324172968.54594.2519525.562594864.521890.259.55134.7524390.062510540527025锚固段A型桩锚固段最短值h2(m)10Ah21.77831根据=1.78查表5，-0.6333Xa10.21.1923Xa20.31.4089cta1-0.40.8953cta2-0.滑面处的位移Xa(m)0.滑面处的转角a(rad)-0.y1234010000.50.0.0.0

16、.10.0.0.0.1.50.0.0.0.20.0.0.0.2.50.0.0.0.30.0.0.0.3.50.0.0.0.40.0.0.0.4.50.0.0.0.50.1.0.0.5.50.1.0.0.60.1.0.0.6.50.1.0.0.70.1.1.0.7.5-0.1.1.0.8-0.1.1.0.8.5-0.1.1.0.9-1.1.1.1.9.5-1.0.1.1.10-2.0.1.1.锚固段位移及内力A型桩Qy43EIxA14473.9151142EIA-73281.07586My42EIxA81391.863634EIA-.0017XyxA0.A/-0.固定支座y-10xyQyMysi

17、gmay(kPa)00.540527025857.0.51.4279.29849.07443.023710.3909.32244.445891600.1.50.4239.3830334668.031491629.20.5210.6317537561.008871666.2.50.6763.41347.597521713.7510530.8835.46433.612281768.3.50.11360.1795653204.582291829.40.14267.7719162023.237341895.198944.50.17482.2109273226.173761964.50.20920.62

18、81187119.523022033.5.50.24491.60441.45912101.60.28093.49952.3962165.6.50.31612.71732.7432222.70.34921.95714.10932269.7.50.37878.50658.87082302.80.40322.63799.0442317.8.50.42076.17851.44852310.90.42941.33168.17712276.9.50.42699.8377.44652212.100.41112.56895.95542111.配筋计算结果：z(m)Q(kN)M(kN.m)抗剪安全系数第1排钢筋

19、直径32mm根数第1排抗弯矩抗弯安全系数第2排钢筋直径32mm根数第2排抗弯矩两排合弯矩合抗弯安全系数01190000106684.6684.006684.6684.0.531077.5290.106684.86.006684.86.1620310145.106684.21.006684.21.1.5930697.596.106684.9.006684.9.21240124072.106684.5.006684.5.2.515501937.558.106684.3.006684.3.31860279048.106684.2.006684.2.3.521703797.541.106684.1.0

20、06684.1.42480496036.106684.1.006684.1.4.527906277.532.106684.1.006684.1.53100775029.2013369.845351.0013369.845351.5.534109377.526.2013369.845351.0013369.845351.637201116024.2013369.845351.0013369.845351.6.5403013097.522.2013369.845351.0013369.845351.743401519020.3020054.768031.0020054.768031.7.54650

21、17437.519.3020054.768031.0020054.768031.849601984018.3020054.768031.0020054.768031.8.5527022397.517.4026739.69071.0026739.69071.955802511016.4026739.69071.0026739.69071.9.5589027977.515.4026739.69070.0026739.69070.1062003100014.5033424.613381.0033424.613381.10.53474.33400.3603625.5033424.613381.0033

22、424.613381.111170.34544.6466276.5033424.613380.106204.39629.130961.11.5-745.34635.36682-120.5033424.613380.106204.39629.130961.12-2306.33858.24725-39.5033424.613380.106204.39629.130961.12.5-3546.32382.173-25.4026739.69070.106204.32944.208281.13-4498.30359.55368-20.4026739.69070.106204.32944.208281.13.5-5191.27927.03178-17.4026739.69070.106204.32944.208281.14-5654.25206.4591-15.3020054.768030.106204.26259.285611.14.5-5914.22306.07467-15.3020054.768030.106204.26259.285611.15-5993.19321.82426-15.2013369.845350.106204.19574.362931.15.5-59