临潼骊山Ⅱ区滑坡前部深基坑开挖效应

发布时间：2018-03-23 15:06

本文选题：骊山Ⅱ　切入点：区滑坡　出处：《西安科技大学》2017年硕士论文

【摘要】：滑坡前部深基坑开挖是滑坡治理工程的大忌,但这种做法屡见不鲜,灾害实例不胜枚举,因此,开展滑坡前部基坑开挖对其产生的影响研究具有重要的理论与现实意义。以临潼骊山Ⅱ区滑坡前部基坑开挖工程为研究背景,采用理论分析、现场监测及数值模拟相结合的方法,分析不同开挖工况下滑坡体、抗滑桩及基坑围护桩变形规律,以期揭示深基坑开挖的滑坡(支挡工程)响应,指导工程实践,主要结果及结论如下:(1)、基于滑坡基本特征及其稳定性理论计算成果,提出滑坡治理方案——“三级支挡+系统排水”及施工监测方案——“多点监测+跟踪预报”,确保了深基坑工程顺利、安全实施。(2)、进行了现场监测试验研究,得到了不同开挖工况下滑坡深部位移、围护桩桩身变形曲线,抗滑桩、围护桩后侧沿桩身土压力、钢筋应力变化曲线,及时分析,跟踪预报,指导了工程实践。①滑坡深部位移曲线整体向背山侧发生倾斜且在滑动面处发生突变;②随着基坑开挖深度的增加,C9围护桩外侧钢筋应力在不断增大,在开挖面以上应力先增大,随后由于土体抵抗作用,在开挖面处开始减小,随后继续增大,再减小,曲线呈“双峰型”;③B10抗滑桩随着基坑开挖深度增加桩身外侧钢筋应力在不断增大,曲线在滑动带处变化较大;④C9、B10桩在不同开挖工况下土压力所测值整体偏小,但在滑动带处变化明显。(3)、运用FLAC~(3D)软件进行滑坡治理前及治理后基坑开挖模拟,分析滑坡体、抗滑桩及围护桩变形特征,模拟结果与实测变形特征基本一致,检验了滑坡治理方案的有效性。
[Abstract]:The excavation of deep foundation pit in front of landslide is a big taboo of landslide treatment project, but this method is common and the disaster examples are numerous, so, It is of great theoretical and practical significance to study the influence of excavation on the front excavation of landslide. Taking the excavation of the front foundation pit of Lishan area in Lintong as the research background, the theoretical analysis is adopted. Based on the method of field monitoring and numerical simulation, the deformation law of landslide body, anti-slide pile and foundation pit retaining pile under different excavation conditions are analyzed in order to reveal the landslide (retaining engineering) response of deep foundation pit excavation and guide engineering practice. The main results and conclusions are as follows: (1) based on the basic characteristics of landslide and its stability theory, This paper puts forward the landslide control scheme, "drainage of three-stage supporting and retaining system", and the construction monitoring scheme, "multi-point monitoring, tracking and forecasting", which ensures the smooth and safe implementation of deep foundation pit engineering, and carries out field monitoring and experimental research. Under different excavation conditions, the deformation curve of the deep landslide, the deformation curve of the retaining pile body, the anti-slide pile, the change curve of the soil pressure and the stress of the reinforcement along the pile body are obtained, and the timely analysis and prediction are made. The results show that the slope of the deep displacement curve of the landslide is inclined to the back of the hill and the stress of reinforcing bar on the outside of the C9 retaining pile is increasing with the increase of the excavation depth of the foundation pit, and the stress above the excavating surface first increases. Then, due to the soil resistance, the stress of reinforcing bar outside the pile body increases with the increase of excavation depth, and then increases, and then decreases. The curve is "double peak" type of anti-slide pile with the depth of excavation increasing, and the stress of reinforcing bar on the outside of the pile body is increasing with the increase of excavation depth. The curve varies greatly in the sliding zone. The measured value of earth pressure of pile 4C9B10 under different excavation conditions is on the whole small, but the change is obvious in the sliding zone. The excavation simulation of foundation pit before and after the landslide treatment is carried out by using the software of FLACC9B10, and the landslide body is analyzed, by using the software of FLAC9B10, which is used to simulate the excavation of the foundation pit before and after the landslide treatment. The deformation characteristics of the anti-slide pile and the retaining pile are basically consistent with the measured deformation characteristics, and the effectiveness of the landslide treatment scheme is tested.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P642.22;TU753

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