Research on the Comprehensive Evaluation of Grouting Quality Based on Fuzzy Rock Engineering System and Variable Fuzzy Set Theory

Grouting is a fundamental technology in engineering construction, and its grouting quality evaluation is a critical scientific problem. Proper and reasonable grouting quality evaluation is vital to ensure engineering safety. Standard research on grouting quality evaluation does not consider the uncertainty in the evaluation process and lacks multi-index comprehensive analysis. Because of the above problems, this paper puts forward a comprehensive evaluation method of grouting quality based on FRES-VFS. Firstly, based on the systematic analysis of relevant factors affecting grouting quality, the comprehensive evaluation of grouting quality is divided into three parts: the groutability before grouting, the rationality of design and construction, and the quality evaluation after grouting. Then, twelve indexes, such as the number of joints in the rock mass, the opening degree of the joint in the rock mass, the water permeability before grouting, the water–cement ratio of grout, the grouting pressure, the design parameters, the hole position, the borehole deviation rate, the construction parameters, the permeability, the compactness, and the durability after grouting, are selected to construct the rating index system. Secondly, the weight of each index in the index system is calculated based on the fuzzy rock engineering system (FRES) method. Furthermore, considering the uncertainty in the comprehensive evaluation of grouting quality, the uncertain mapping between evaluation grade and evaluation index is established using variable fuzzy set (VFS) theory. Finally, the comprehensive evaluation method based on FRES-VFS is applied to the Huanggou Pumped Storage Power Station grouting project in China, which provides a new idea for the comprehensive evaluation of grouting quality.