为了准确评估中小型在役桥梁安全状况,提出利用灰色关联故障树分析法对中小型在役桥梁进行安全预警研究。首先建立中小型在役桥梁安全预警故障树;其次采用专家打分法确定故障树各底事件的不可靠概率,得到各底事件的重要度,并利用灰色关联理论求出故障树各底事件的关联度;根据预警理论将各底事件的关联度与各底事件的重要度加权平均确定预警值所处的警限区间,从而确定警度及需要发出的预警信号灯,完成预警工作,并提出相应的预控对策。最后通过实例分析,结果表明该方法具有可行性与实用性。
In order to accurately evaluate the safety situation of middle and small existing bridge,it was put forward to conduct early- warning study on middle and small existing bridge by using the fault tree method with gray correlation. Firstly,the fault tree about early- warning of middle and small existing bridge was established. Secondly,the unreliable probability of each basic event in the fault tree was determined by expert evaluation method,then the importance of each basic event was obtained,and the correlation degree of each basic event in the fault tree was deduced by using gray correlation theory. The warning limit interval where the early- warning value existed was determined by weighted average on the correlation degree and importance of each basic event based on the early- warning theory,thereby,the warning degree and early- warning signal lamp needed to be sent out were determined. The early-warning work was finished,and the corresponding prevention and control measures were proposed. Finally,the method was applied to an example,and the results proved the feasibility and practicability of the method.