Experimental investigation on water/gas resistance and strength properties of clinoptilolite/Na-PAA amended compacted clay cover

Abstract

Compacted clay is an effective and economical engineering barrier for seepage prevention and gas blocking in landfills (including tailings pond, landfill, etc.). In addition to the lack of durability such as desiccation cracks of compacted clay modified by clinoptilolite and sodium polyacrylate, it is also necessary to consider the changes of engineering properties such as water holding capacity, water and gas resistance, and strength of compacted clay. Therefore, through oven evaporation test, flexible wall permeability test and unconfined compressive strength test, this paper studies the water retention, permeability and strength characteristics of compacted clay with different amounts of clinoptilolite and sodium polyacrylate. Orthogonal experiment L16(45) was used to optimize the amount of clinoptilolite and sodium polyacrylate and the compaction conditions, and further combined with the analytic hierarchy process (AHP), the factors affecting the water retention, permeability and strength of the compacted clay before and after the modification of clinoptilolite and sodium polyacrylate were discussed simply and quickly, and the applicability of the orthogonal experiment traditional analysis method and the analytic hierarchy process in the modified compacted clay of clinoptilolite and sodium polyacrylate was studied.