摘要
结合兰州某什字立交改造工程基坑的特点,对基坑围护桩顶水平位移、周围地表沉降、周边建(构)筑物沉降等监测结果进行了分析,采用FI。AC3D软件模拟基坑开挖过程,对排桩加钢支撑支护下的基坑变形规律及变形影响因素进行了研究.结果表明:1)基坑固护桩顶位移、基坑周边地表沉降等随着基坑开挖深度增加而同步变化.围护桩顶水平位移最大为15.8mm,桩顶竖向位移最大为11.5mm.2)敞开段地表沉降呈三角形分布.离基坑越近沉降越大,最大为11.4mm;暗埋段地表沉降呈抛物线形分布.离坑边5~8ITI处沉降较大,最大为15.7mm,坑边和较远处沉降较小.3)将数值模拟结果与监测结果进行对比,两者变化趋势基本一致且较接近,说明数值分析结果可靠、支护结构支护效果理想.
In combination with the characteristics of the foundation pit of a reconstruction project in Lanzhou,the monitoring result of displacement of pile top, the settlement around the founda- tion pit and the settlement of surrounding building are analyzed. The deformation rules and the influencing factors of the pile-steel support foundation pit are analyzed by using FLAC3D soft- ware to simulate the excavation process of foundation pit. The results show as follows: 1) the horizontal displacement of foundation pit and the foundation settlement increase with the increase of the excavation depth of the foundation pit,and the maximum value of the horizontal displace- ment of pile top is 15.8mm and the maximum value of settlement of pile top is 11.5ram; 2) the ground surface settlement of the opening section is triangular distribution: the closer the section is,the greater the ground surface settlement is,and the maximum value is 11.4mm; the ground surface settlement of the buried section is parabolic distribution: the ground surface settlement is maximum around the pit at about 5~8m and the value is 15.7ram while the ground surface settle- ment is small at both the edge of the pit and far away from the pit; 3)the simulating result and the actual monitoring result are similar ,and their variation rules are almost the same, so the simu- lating result is reliable and the supporting effect of the pile-steel support structure is ideal.
出处
《兰州交通大学学报》
CAS
2015年第6期38-44,54,共8页
Journal of Lanzhou Jiaotong University
关键词
基坑
监测
桩顶位移
地表沉降
数值模拟
foundation pit
monitoring
displacement of pile top
surface settlement
numericalsimulation