基于云模型的长时停工隧道初期支护质量评价

Quality risk evaluation for the initial internal supports of the long-lasting shutdown tunnels based on cloud model

为解决长时停工隧道初期支护质量评价中的定性概念与定量描述的转换问题,基于云模型理论,根据相关文献和标准规范,建立了长时停工隧道初期支护质量评价指标体系,并将评价因子进行等级分类,通过正向正态云发生器生成对应的云模型参数,再结合各评价指标的权重,获得云模型的综合确定度,最后利用最大隶属度原则确定长时停工隧道初期支护质量状态等级。基于该模型,对2个长时停工隧道初期支护进行了质量评价,结果表明：本文构建的长时停工隧道初期支护质量评价模型与模糊综合评价模型的评价结果相吻合,验证了云模型的可行性和合理性。

The given paper is inclined to present a quality evaluation model for the longtime-forsaken tunnels based on the cloud model theory. As a matter of fact, the evaluation index system of the initial support quality of the forsaken tunnels should be established based on the 8 first-level evaluation indicators, including the water leakage, the steel-plate deterioration or getting rusty, and the anchorage effect, etc. In order to convert the qualitative indexes in the indicative system into the quantitative description indexes, we have managed to identify and determined the weights of the evaluation factors via the analytic hierarchical process, which can be divided into 4 grades, namely, B （better） , 1A （general）, 2A （range）, and 3A （poor） , based on the cloud model theory, whereas the forward cloud generator FCG can be used to generate the expected value En, the positive random number X, the cloud droplet and the other quantization items. According to the two boundary constraints [ Imin, Imax ] of the evaluation grades and the formula Ex = （Imin ＋ Imax, ） / 2, En = （Imax - Imin ） / 6, He = K （ its coefficient K is set to 0. 02 ）, we have worked out the cloud model parameters En and He. And, next, the comprehensive deterministic factor Y can be deduced to be equal to the accumulated product of each index weight and its corresponding definite degree. Thus, finally, taking the advantage of the maximum membership principle, we can deduce the quality grade of the initial or original support of the tunnel that have been forsaken for a long-lasting period. Based on this model theory, the quality evaluation of the initial support of the two tunnels that have been shut down for long years should have been generally biased poor. The results of our study have thus been proven well in agreement with the results of the fuzzy comprehensive evaluation model. Hence, the cloud model has thus been verified feasible and rational and in turn can be expected to provide an innovative idea or thinking line for similar research areas.