成果名称：Estimating the Frequency of Exposure to Uncertain Hazards Impact of Wind Conditions on Concrete Dam

作者：Shu Chen; Ya Tian; Lianghai Jin; Lei Xiang

期刊：Journal of Construction Engineering and Management

摘要：Due to the narrow construction site, intensive construction, and constant strong winds, some concurrent activities during concrete dam construction are proven to lead to space conflicts and increase the frequency of exposure to hazards. Despite some valuable contributions, the current methods for quantifying exposure frequency are still subjective and inadequate for reliable safety evaluation. Therefore, this study provides a formal approach to identify exposure under dynamic wind loads and to estimate exposure frequency to scrutinize dynamic interactions at construction sites. In this study, first, the force of hazard with wind loads is analyzed to identify the impact of potential hazards from vertical concrete transport in an undesirable event. Second, combined with the concrete dam construction cycle process and the operating time characteristics, the probability of hazards and victims concurrently appearing in an overlapping space is calculated to measure the possibility of disastrous events from the perspective of spatial and temporal attributes. Then, the exposure frequency is expressed using statistical information on wind conditions, location information on the site layout, and mechanical motion parameters. In contrast to traditional risk-assessment methods, the proposed model combines the uncertainty of wind and the probability of hazards and victims simultaneously appearing in an overlap into a more rigorous safety perspective. Finally, the model’s capability of hazard exposure assessment is demonstrated and tested by applying it to a case study of a major real-world construction project. The results show that the novel methodology is able not only to quantify the exposure frequency with the contribution of the influence of strong winds but also to assess the risk of dam construction projects. Furthermore, this method will provide an important objective and precise evaluation tool for hazard exposure.

论文创新点：当前我国在建拟建水电工程大多处于大渡河、雅砻江、金沙江、怒江、澜沧江等西部干热河谷。由于河谷深切、峰峦重叠、岸坡陡峭，施工区狭管效应显著，极易引发焚风和山谷风，形成频繁的灾害性大风。而大坝混凝土浇筑过程中，缆机吊罐的偏移量主要取决于风力特征和吊罐的整体重量。鉴于此，针对吊罐的不同状态和不同的风力等级，建立了识别和量化风力作用下大坝浇筑交叉作业空间冲突的模型。

论文链接：https://ascelibrary.org/doi/full/10.1061/%28ASCE%29CO.1943-7862.0001972