Investigation on desiccation crack initiation and development of Tianjin Binhai dredger filling soils with fiber- reinforced

Abstract

The increased porosity and permeability caused by cracking can pose a leachate hazard to municipal landfills. This paper describes a procedure for the evaluation of the cracking tendency during drying process on clayey soil. Based on desiccation experiments, it was found possible to estimate the moisture content, fractality and cracking characteristics, and the effect of fibre corporation incorporation on the cracking propagation of cohesive soils collected in dredger filling area in Tianjin. Based on this analysis, the following conclusions may be presented: fibre incorporation does not change the evaporation pattern of dry cracks, but can reduce the critical moisture content of cracking, which is reduced by 22.1% at 0.5% incorporation. The fractility also shows a continuous decreasing trend with the increase of fibre incorporation,which is reduced by 52.9% at 0.5% incorporation compared to the original state. The cracking characteristics were divided into three development stages. The results showed that the critical moisture content of the soil body was significantly reduced (18.8–7.8%) in stage II after fibre addition, and the cracks did not divide the soil body in stage III, which maintained the integrity of the soil body. The cracks had significantly decreased in length and width after fibre incorporation, and the number of cracks increased significantly. It indicates that the cracks cannot form through the cracks after fibre incorporation, and the crack resistance is obviously improved, which reduces the permeability of the soil.