摘要
为解决深基坑施工风险评价中存在多维监测指标融合的客观性不足、用断面风险信息代替基坑整体风险的问题,建立基于投影寻踪及信息扩散的深基坑施工风险动态评价方法。对深基坑施工的风险等级标准体系进行数据挖掘,得到能够反映各指标权重的最佳投影方向向量,从而将多维监测数据投影成一维风险值。运用信息扩散理论,将多个断面风险信息扩散到整个基坑工程上,以实现深基坑工程风险的综合评价。并将该方法应用于长沙一个地铁车站深基坑项目。结果表明,多维监测指标对同一监测断面风险值的贡献度不同,不同监测断面携带的风险信息亦不相同,对基坑整体风险的动态评价既应考虑不同监测指标的贡献度,还应兼顾不同断面风险值的影响。
In order to solve the problem about the defect in guaranteeing objectiveness in fusion of multi-dimensional indicators and avoid the risk assessment of the entirety pit instead of monitoring section. A method of risk dynamic assessment was worked out for deep excavation based on projection pursuit and information diffusion theory. Firstly, a data mining process for the grading standards of the risk in construction of deep excavation was carried out, and then the optimal projection direction vector which can reflect the weight of each index was obtained. Therefore the multidimensional monitoring data can be pro- jected into one-dimensional risk values. Subsequently, through spreading the risk information of multiple cross sections over the whole foundation to make a comprehensive evaluation of the whole excavation based on information diffusion theory. Finally, the above mentioned method was applied in deep excavation pro- ject of a metro station in Changsha Hunan province. The results show that the contributions of multi-dimen- sional indicators to value-at-risk in the same section are different, and also the pieces of information car- fled by different sections are not the same, and that for the assessment what need to be taken into accout are not only the different contributions of the indicators, but also the influence of the different monitoring sections.
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2015年第2期147-152,共6页
China Safety Science Journal
基金
国家自然科学基金资助(51178386)
关键词
投影寻踪
信息扩散理论
深基坑
动态
风险评价
projection pursuit
information diffusion
deep excavation
dynamic
risk assessment
