深大基坑开挖对邻近历史风貌建筑基础变形的影响

发布时间：2018-02-21 17:59

本文关键词： 深基坑有限元地下连续墙历史风貌建筑基础地面沉降倾斜值　出处：《河北工业大学》2013年硕士论文　论文类型：学位论文

【摘要】：本文针对天津市某基坑工程开挖是否会对周围邻近历史风貌建筑产生不良影响这一问题，依据现场中的实测数据结果，采用有限元软件ABAQUS，对三维基坑变形性状进行研究。实际监测和计算模拟结果表明： 1.监测的支撑轴力大多数为正，承受压力，第一道支撑内力相比其余几道内力大，随着开挖深度增加支撑内力逐渐减小。支撑水平位移普遍向基坑内移动，且第一道支撑的位移值最大，随着开挖深度增加支撑位移值逐渐减小。 2.监测的地连墙水平位移向基坑内移动，由于东面和北面墙体早已作为其他基坑支护结构，变形较小，中心附近水平位移分别为0和10mm以下。另两面墙体变形较大接近100mm。模拟的西面和南面墙体水平位移变化趋势和监测结果吻合，随着埋深的变化墙体位移呈现倒三角式变化趋势，与监测结果吻合。同一深度处地连墙中间处位移值比四角处大。 3.监测的基础沉降在开挖后大部分为0，只有11、12点沉降值为0.01mm。模拟的位移离基坑越近，其数值越大，越远其数值越小，最大和最小沉降值分别为0.0178m和0.0033m。模拟的基础主拉应力四角处相比中间而言数值较小，但总体分布数值不大。局部倾斜值均小于规范中的允许值0.002，满足规范的要求。分析结果认为： 1.对深基坑进行现场监测，分析各项监测内容的变化规律，对邻近历史风貌建筑基础变形规律进行了预测，指出动态监测在保障安全施工中发挥着重要作用。由结果看出可以忽略基坑开挖对基础变形造成的影响。 2.对基础在基坑分步开挖过程中的反应进行分析研究，将实测结果和有限元分析结果进行对比，变形规律基本一致，，说明ABAQUS可以用于基坑工程，并指导基坑设计和施工。基坑工程用三维有限元分析能够得到和实际测量接近的结果本文的得分析结果可以用于基坑工程的变形计算及对邻近建筑物产生的影响预估。
[Abstract]:This paper aims at the question whether the excavation of a foundation pit in Tianjin will have a bad effect on the surrounding historical buildings, and according to the measured data in the field, The finite element software Abaqus is used to study the deformation behavior of three-dimensional foundation pit. The actual monitoring and simulation results show that:. 1. Most of the supporting axial forces monitored are positive, bearing the pressure. The first bracing internal force is larger than the other several internal forces, and gradually decreases with the increase of excavation depth. The horizontal displacement of the bracing generally moves to the foundation pit. The displacement value of the first bracing is the largest and decreases gradually with the increase of excavation depth. 2. The horizontal displacement of the monitored ground connection wall moves to the foundation pit. As the east and north walls have already been used as other foundation pit supporting structures, the deformation is relatively small. The horizontal displacement near the center is below 0 and 10 mm, respectively. The deformation of the other two walls is close to 100mm. the horizontal displacement of the west and south wall is consistent with the monitoring results, and the displacement of the wall shows a trend of inverted triangle with the change of the buried depth. The results are in agreement with the monitoring results. At the same depth, the displacement value of the middle part of the connecting wall is larger than that of the four corners. 3. The monitored foundation settlement is mostly 0 after excavation, and only the settlement value of 11 ~ 12 points is 0.01mm. the closer the simulated displacement is to the foundation pit, the greater its value is and the smaller its value is. The maximum and minimum settlement values are 0.0178m and 0.0033mrespectively. Compared with the center of the four corners of the basic principal tensile stress, the simulated values are smaller than the values of the total distribution, and the local tilting values are smaller than the allowable values of 0.002 in the code, which meet the requirements of the code. The results of the analysis show that:. 1. The field monitoring of deep foundation pit is carried out, and the variation law of each monitoring content is analyzed, and the deformation law of adjacent historic buildings is forecasted. It is pointed out that dynamic monitoring plays an important role in ensuring safe construction, and the influence of excavation on foundation deformation can be neglected from the results. 2. The response of foundation in the process of excavation by steps is analyzed and studied. The measured results are compared with the results of finite element analysis, and the deformation law is basically the same. It shows that ABAQUS can be used in foundation pit engineering. And guide the design and construction of foundation pit. Three-dimensional finite element analysis for foundation pit engineering can get results close to actual measurement. The results obtained in this paper can be used to calculate the deformation of foundation pit and predict the influence on adjacent buildings.
【学位授予单位】：河北工业大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU433

【参考文献】