碗扣式支架安全状态综合评估方法

Comprehensive safety state assessment method of cuplok scaffolding

为评估碗扣式模板支撑架的安全稳定性,提出碗扣架安全状态评估方法。该方法首先选取9个常态监测项目作为评价指标,根据不同杆件间距、顶底杆自由长度和碗扣节点刚度选取多套碗扣架,提取与指标相关数据。然后采用主成分分析法分析各指标相关性,构建碗扣架安全状态评估方法,按照碗扣架安全状态得分评估碗扣架安全等级。最后以西安市辛家庙立交桥为例,通过MIDAS/CIVIL有限元分析程序分别对同一桥跨的24套碗扣架方案进行模拟试验,通过特征值分析、屈曲分析和静力分析提取与指标相关的数据,用所选取的指标对该方法进行验证。研究结果表明:选取的安全评价指标能够表征碗扣式支架的整体刚度、安全储备能力、静力特性和稳定性,现场测量方便,该方法在碗扣架安全评价中合理有效,具有较强的实用性;将主成分分析法引入碗扣架安全评估是可行的,评估结果能够综合反映各评价指标的重要性和碗扣架的实际安全状态,可为碗扣架的安全分析和评价提供理论指导。

To assess the safety and stability of cuplok scaffolding, the comprehensive assessment method was put forward. Firstly, 9 normal monitoring subjects were chosen as the assessment indexes and the data related to indexes was extracted from a series of cuplok scaffoldings with different bar spacing, free length of top and bottom vertical bars, and stiffness of joints. Then the principal component analysis method was introduced to analyze the correlation among each index and create the comprehensive assessment method of cuplok scaffolding, which can give out the safety grade according to the safety state evaluation score. Finally, taking Xinjiamiao overpass in Xi＇an as an example, 24 different cuplok scaffolding designs of the same span were analyzed through eigenvalue analysis, buckling analysis and static analysis by MIDAS/CIVIL. And the method was verified through the data extracted from the analysis. The results show that the safety assessment indexes can absolutely express the integral rigidity, safety stock, static stress state and stability, and can be easily measured in-place. So these indexes are well chosen, reasonable and effective in the assessment. The introduction of principal component analysis into the cuplok scaffolding safety assessment, which can reflect the importance of each assessment index and the actual measured safety status of cuplok scaffolding, is feasible. This method has a strong practicability and is expected to provide theoretical guidance for safety analysis and assessment of cuplok scaffolding. 8 tabs, 4 figs, 16 refs.