基于模糊集重心理论的膨胀土胀缩等级评判

膨胀土及其对实际工程稳定性的影响问题有基础工程界的“癌症”之称。而准确评定膨胀土的等级进而有针对性的采取工程措施是治理膨胀土的关键,然而传统的膨胀土胀缩等级评判是采用模糊综合评判理论进行的,该方法易丢失评判信息,从而影响评判结果的科学性和可信度,基于此,首先通过引入模糊集重心理论来弥补传统模糊综合评判方法的不足,然后在此基础上选取五个对膨胀土胀缩等级评判影响较大的因素,并以正态分布作为其隶属函数,采用加权平均值法确定各因素权重值,建立起基于模糊集重心理论的膨胀土胀缩等级评判方法。最后以某市政道路一处膨胀土为例,阐述了基于模糊集重心理论的膨胀土胀缩等级评判的计算程序,并证明了此方法的合理性与有效性。

Shrinkage and Expansion of Expansive Soil Judgment Based on Theory of Barycenter of Fuzzy Set

The expansive soil and its influence on the engineering stability of foundation engineering is called ＂cancer＂. The accurate evaluation of expansive soil grades and then take engineering meas- ures is the key to treatment of expansive soil, However,the traditional shrinkage and expansion judgment of expansive soil is carried out by the method of fuzzy synthetical assessment, and the method is easy to lose the evaluation information, then influences scientificity and reliability of the result. Based on this, the author introduces the theory of barycenter of fuzzy set to make up for the traditional fuzzy comprehensive evaluation method. Based on this theory, the author chooses five more important influential factors for shrinkage and expansion of expansive soil judgment, then the author uses the normal school as its sub- ordinate function and uses the theory of the weighted average to conform weights of the whole factors. Thus the method of shrinkage and expansion of expansive soil based on the theory of fuzzy set has been established. Finally the author uses an expansive soil of a municipal road as an example, expounds the calculation program of shrinkage and expansion of expansive soil judgment based on the theory of barycenter of fuzzy set ,and it validates rationality and validity of the textual method.