Risk Assessment Of Deep Foundation During Construction Based On Monitoring

The risk factors is complex and changeable during construction process of deepfoundation pit, No matter which aspects appear problem, the consequencesare unforeseeable. How can accurately judge the risk factors in each period and carryout effective control, reduce the occurrence of accidents, which has been manyexperts and scholars continue to discuss the issue of research. According to theconventional process of risk assessment to evaluate the safety of foundationpit, which is mainly based on expert experience to qualitative analysis,It is limited toguide construction because of great uncertainty, certain difference an engineeringactual.Through the survey on a large number of deep foundation pit accident foundthat accident can be monitored through out the analysis of the databasically.Therefore, how to make full use of the field monitoring data were used toassess the risk of deep excavation during construction is a research topic of greatconcern.In this paper, through statistical analysis and investigation of deep foundation pitengineering based on Guangxi Jiuzhou International Building in foundation pitengineering. To study systematically construction period risk assessment methodbased on the monitoring data of deep foundation pit. The main work and conclusionsare as follows:(1) To analyzed for the accident in the course of deep excavation constructionfrom two aspects of deep foundation pit in the cause of the accident and the accidentphenomenon based on the existing literature,points out that the design andconstruction is the two leading cause of accidents.(2) Described in detail the basic concept of construction, characteristics of deepfoundation pit engineering risk; risk assessment of several main analysis methods arecompared on the deep foundation pit; risk evaluation steps in detail, and summarizesthe commonly used risk measures.(3) To establish a risk assessment index system based on the monitoring dataduring the construction of deep foundation pit engineering; Alarm value as the most senior risk limits on safety monitoring project was classified;Risklosses wereestimated by the expert investigation method; The risk is defined as the basis, toestablish the riskassessment model based on the single field monitoring data,meanwhile establish a comprehensive risk dynamic evaluation model based on thecomprehensive field monitoring data; Analysis the possible dangerous state and risksource based on the abnormal monitoring data of each monitoring project,so thatcontrol measures more targeted.(4) In light of the current situation of Guangxi Jiuzhou International Buildingfoundation,the analysis of monitoring data were screened out as monitoring projectindex foundation pit safety evaluation and the establishment of evaluation system.Thefirst analysis is the single monitoring project on risk of the whole constructionprocess, then combined with the respective weights of risk degree evaluation offoundation pit.Take measures according to the risk acceptance criteria. The objectivereliability risk assessment based on process monitoring provide the reference for thesimilar engineering.