摘要

近些年来我国城市地铁建设规模巨大，地铁施工安全事故率呈上升趋势。监测手段可以为安全事故预防和控制提供信息。识别风险部位，优选监测项目对于事故预防非常重要。然而，我国规范中对于监测项目选择规定较为笼统，未考虑实际工况。为对规范进行补充，本文在对地铁深基坑工程基本信息风险评估的基础上，对施工监测项目选择方法进行了系统化研究。

首先，论文对地铁深基坑施工监测、风险评估和监测法规进行详细论述，提出监测项目选择问题研究的必要性。其次，论文提出采用“揭示风险贡献率”描述监测项目表征风险能力。并采用专家调查、监测规范比较和监测案例研究三种方法进行调研，将监测项目揭示风险贡献率数值量化，确定监测项目优先度分区标准。同时，以工程风险特征参数量化识别为基础，构建出基于工程基本信息的地铁深基坑施工风险等级划分体系，对基坑总体和风险部位的风险等级进行识别。再次，通过分析监测项目机理和借鉴监测项目揭示风险贡献率成果，建立风险部位和监测项目优先度体系。以基坑总体与风险部位的风险等级为前提，进行监测项目优先度调整，最终确定实际工程监测项目优先度分区。最后，论文结合某地铁深基坑监测实际案例，运用本文研究得出的选择方法进行实证分析，并与规范和实际监测进行对比。

论文提出的监测项目选择方法适合地铁深基坑施工前，以供监测方案制定参考。然而，结合不同决策者对于风险接受度不同以及施工全过程动态监测项目调整有待进一步研究与探讨。

关键词：风险评估地铁深基坑风险部位监测项目选择揭示风险贡献率

Abstract

In recent years,urban’s metro development is in large scare while safety accident rate is onthe rise in China during construction stage. Useful information for theprevention and control of accidents can be provided by monitoring. It is veryimportant to identify risk position accuratly and select monitoring itemsproperly for prevention. However, due to the regulation related to monitoring itemsselecting lacking of focalization, the actual condition risk is not considered inour country. In order to supplement the lack of specification, making asystematic research on monitoring items selecting based on the risk assessment ofthe basic engineering information during the deep foundation pit construction phaseof metro is needed.

First of all, onthe detailed analysis of the research of deep foundation pit monitoring, risk assessmentand related laws and regulations of metro, it is found that the study on monitoringitems selecting is vitally important. Secondly, it puts forward the concept of"revealling the risk contribution rate" for describing the nature of monitoringitems innovatively. After three methods（i.e. the investigation of experts investigation, the comparison ofmonitoring codes and monitoring cases) were applied to calculate quantitativelythe priority of monitoring items, the final quantitative value and standard of monitoringitems priority is determined. At the same time, based on the quantitativeidentification of engineering risk characteristic parameters, building the riskrating standard system based on the basic engineering information can achieveto identify the risk level of overall and risk position for deep foundation pitof metro. Again, through the analysis of the monitoring mechanism and theresult of revealling the risk contribution rate, the priority system between riskposition and monitoring items is established. The final monitoring items prioritypartition adjustmentent were based on the risk level of overall and riskposition. Finally, a corresponding study on the actual case of a deepfoundation pit of metro monitoring is to verify this method for monitoring itemsselecting by comparing the result from this method, specification and theactual project.

The paper introducesthe method of monitoring items selecting for deep foundation pit of metro,which is suitable for the stage of decision-making before excavation. However,taking into account different decision-makers for risk acceptance and on theadjustment for dynamic monitoring should be discussed and evaluated during thewhole construction stage for monitoring items selection in the future.

Key words：Risk Assessment  Deep Foundation Pit of Metro

Risk Position  Monitoring Items Selecting  Reveal the Risk Contribution Rate