基于DBO模型的焊接式顶升模架施工安全风险动态评价

杨航

摘要

我国的超高层建筑是从1976年开始发展起来的，到1990年之后进入了超高速发展的阶段。超高层建筑在中国乃至全世界兴起的同时，就其高度高、施工难度大、不易围护、安全风险较高等特点，超高层建筑施工工艺技术也在发生着很大的变化。目前，很多的超高层施工对核心筒进行施工时都选用了焊接式顶升模架系统。焊接式顶升模架系统虽然在超高层建筑施工的过程中带来了很大的便利，但是它体积大、重量大、难控制，一旦有安全事故发生就会十分严重。对于开展和加强对焊接式顶升模架系统进行安全评价研究的工作变得势在必行，探寻导致工程事故的各种主要原因和相关途径，对其采取因地制宜的采预防控制手段，达到对焊接式顶升模架系统失事造成的危害进行预防或者说减少。

本文通过建立DBO模型对工程实例中焊接式顶升模架失稳事故进行了定性分析，并列举了安全屏障对各个事故和事件进行了隔离，之后运用动态故障树的分析方法和动态事件树的分析方法对焊接式顶升模架失稳事故的失效概率进行了定量分析，得出不均匀顶升、局部荷载过大、标高控制失误这几个在施工过程中需要重点关注的点，并评估了工程实例的安全风险水平。最后结合结构的设计计算和现场应力检测结果验证了上述DBO模型完成的分析结果，增强了分析结果的说服力，同时也验证了DBO模型在焊接式顶升模架系统施工过程中应用的可行性。

本文提出的DBO模型整合了静态Bow-tie模型的有点，同时弥补了其定量分析方面的不足，相信在之后的研究过程中会有很好的发展和运用。

关键词：超高层建筑  安全风险评价  焊接式顶升模架  DBO模型  动态故障树

Abstract

China's super high-rise building began to develop from 1976, and it entered the stage of ultra-high speed development after 1990. With the rise of super high-rise buildings in China and even in the world, the construction technology of high-rise buildings was also undergoing great changes in terms of their high height, difficulty in construction, difficulty in enclosure, and high safety risks. At present, many super high-rise constructions had adopted the welded overhead formwork system when constructing the core tube. Although the welded overhead formwork system brought great convenience in the construction of super high-rise buildings, it was bulky, heavy, and difficult to control. Once a safety accident occurs, it could be very serious. It was imperative to carry out and strengthen the work on the safety evaluation and research of welded overhead formwork systems, to explore the various causes and related approaches that lead to engineering accidents, and to adopt measures for mining prevention and control that suit local conditions and achieve welding. The damage caused by the failure of the lifter system was prevented or reduced.

In this thesis, the DBO model was used to qualitatively analyzed the instability of welded overhead jigs in engineering examples, and the safety barriers were listed to isolate the accidents and events. After that, the dynamic fault tree analysis method and the dynamic event tree were used. The analytical method quantitatively analyzed the failure probability of a welded overhead jig frame failure accident, and concluded that points of non-uniform lifting, excessive local loads, and elevation controlled errors need to be paid attention in the construction process and evaluated. The safety risk level of engineering examples. Finally, combined with the design calculation of the structure and field stress test results, the analysis results of the above DBO model were verified, the persuasiveness of the analysis results was enhanced, and the feasibility of the application of the DBO model in the construction process of the welded lift formwork system was also verified.

The DBO model proposed in this thesis integrates the static Bow-tie model and makes up for the lack of quantitative analysis. It is believing that there will be good development and application in the subsequent research process.

Keywords: Super High-rise Building; Security Risk Assessment; Welded Lifting

Formwork; DBO Model; Dynamic Fault Tree