Investigation of Compression Modulus and Consolidation Coefficient of Cement Solidified Peat with Ultra High Water Content

Abstract

Abstract: Peat has the characteristics of high water content, high organic matter content, large void ratio and low shear strength. Chemical solidification can be used to improve the bearing capacity and deformation resistance of the soft ground. By conducting one-dimensional consolidation test, effects of water content, organic content, pH value, cement content and sand particle size on compression modulus and consolidation coefficient of cement solidified peat were systematically investigated. The results show that the amount of hydration reaction induced gel increases with the increase of cement content and curing age, resulting in an increase in compression modulus of solidified peat. By decreasing water content from 600% to 300%, the compression modulus of solidified peat increases by 3.5 times. The compression modulus of solidified peat decreases by 50% as organic content of peat increase from 40% to 80% (mass fraction). Moreover, the compression modulus of solidified peat decreases by 15.8% as pH value decrease from 7.0 to 3.5. Based on compression modulus and consolidation coefficient of solidified peat, water and cement contents have the greatest influence on solidified peat, followed by organic content and pH value. The modulus of solidified peat can be increased by adding quartz sand, and the smaller the size of sand particle, the greater the compression modulus.

Key words: high water content, peat, solidification, compression modulus, consolidation coefficient, foundation engineering

CLC Number:

TU41

TAO Ran, WANG Rong, FAN Yanqi, DONG Junquan, SHI Jiangwei. Investigation of Compression Modulus and Consolidation Coefficient of Cement Solidified Peat with Ultra High Water Content[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(1): 60-67.

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