摘要
为增加地铁基坑变形预警的可靠性和准确性,提出利用尖点突变理论和速率比值法构建基坑变形预警模型,即先利用尖点突变理论从累计变形和变形速率两方面评价不同监测对象的稳定性,当评价对象处于不稳定状态时,应立即停工,并采取相应加强措施;反之,再进一步利用速率比值法对各监测对象在不同阶段的稳定性程度进行评价,并根据状态划分,制定相应的处理措施。实例研究表明:累计变形的突变分析结果和变形速率的突变分析结果较为一致,得出各监测对象均处于稳定状态,说明基坑的稳定性较好,其施工对周边近接建筑物的影响有限。同时,速率比值法可判断各监测对象在不同时间节点处的稳定状态,进而实现基坑变形的实时预警,有效保证了基坑施工过程中的信息化施工管理,为基坑变形预警研究提供了一种新的思路。
In order to enhance the reliability and accuracy of the deformation early warning of subway foundation pit,it is proposed herein to build up the early warning model for the foundation pit deformation with the cusp catastrophe theory and rate ratio method,i.e.evaluating the stabilities of different monitored objects from the aspects of both the cumulative deformation and the deformation rate with the cusp catastrophe at first.When the evaluated object is in an unstable state,the construction is necessary to be immediately shut down and the relevant reinforcement measure must be taken as well.Otherwise,the rate ratio method is then adopted to evaluate the degrees of the stabilities of all the monitored objects at different stages and make the corresponding treatment measures according to the relevant division of the states.The study of the actual case shows that the result from the catastrophe analysis of the accumulative deformation is more coincided with that from the catastrophe analysis of the deformation rate;from which it is obtained that all the monitored objects are in stable state;that indicates that the stability of the foundation pit is better and the impact from its construction on the adjacent buildings is limited.Meanwhile,the states of the stabilities of all the monitored objects at different time nodes can be judged with the rate ratio method,and then the real-time early warning of the deformation of the foundation pit can be realized for effective guarantee of the informationized construction management during the construction of the foundation pit;which provides a new idea for the study made on the early warning of foundation pit deformation.
作者
张志会
张明
王先斌
ZHANG Zhihui;ZHANG Ming;WANG Xianbin(State Nuclear Electric Power Planning Design and Research Institute Co.,Ltd.,Beijing 100095,China)
出处
《水利水电技术》
北大核心
2019年第7期174-180,共7页
Water Resources and Hydropower Engineering
关键词
地铁基坑
尖点突变理论
稳定性评价
速率比值法
变形预警
subway foundation pit
cusp catastrophe theory
stability evaluation
rate ratio method
deformation early warning
作者简介
张志会(1980-),男,高级工程师,学士,主要从事工程勘察及地基处理。E-mail:1358024457@qq.com。
