JOURNAL OF YANGTZE RIVER SCIENTIFIC RESEARCH INSTI ›› 2017, Vol. 34 ›› Issue (8): 130-134.DOI: 10.11988/ckyyb.20160501

• ROCK-SOIL ENGINEERING • Previous Articles     Next Articles

Degradation Effect of Humic Acid on Long-term Strength of Solidified Sludge Soil

WU Jun1, 2, 3, WANG Hong-xing1, 2, 3, TAN Yun-zhi1, 2, 3, HUANG Long-bo1, 2, 3, HU Mo-zhen1, 2, 3   

  1. 1.Hubei Provincial Key Laboratory of Construction and Management in Hydropower Engineering, China Three Gorges University,Yichang 443002,China;
    2. Key Laboratory of Geological Hazards on Three Gorges Reservoir Area under Ministry of Education, China Three Gorges University,Yichang 443002,China;
    3.Institute of Problematic Soil Mechanics, China Three Gorges University, Yichang 443002,China
  • Received:2016-05-23 Revised:2016-11-03 Online:2017-08-01 Published:2017-08-18
  • Contact: 汪洪星(1983-),男,湖北咸宁人,讲师,博士,主要从事软土加固及土体本构模型研究,(电话)13986829679(电子信箱)。
  • Supported by:
    水电工程施工与管理湖北省重点实验室(三峡大学)开放课题(2014ksd14); 三峡大学博士科研启动基金(KJ201413036); 三峡大学科研创新基金(2015CX035)

Abstract: Studies on the effect of humic acid on the long-term strength of solidified sludge soil, are of great importance. In this research, sludge with low organic matter content was solidified by mixtures of cement, metakaolin,and lime, etc. On this basis, humic acid in proportion of 0.5%, 1.5%, 3% and 4.5%, 6%, respectively, was added into the sludge. The development laws of bending strength, stress-strain relationship and failure strain of solidified sludge soil under standard curing condition for 240 days were obtained.Results revealed that 1) under the joint actions of humic acid and inherent humic acid slowly released from organic matters of the sludge, the initial bending strength of solidified soil increased rapidly and then decreased to different extents; 2) when humic acid content increased from 0.5% to 6%, the bending strength of solidified soil at different ages almost degraded to a certain degree, and the balance between solidification and humic acid erosion occurred in advance, from the 180th day to the 60th day; 3) the failure mode of solidified soil with high content of humic acid experienced the tendency from plastic failure to brittle failure, and then to partial plastic failure, and the bigger content of humic acid is, the more obvious the action of plastic failure is.

Key words: solidified sludge soil, humic acid, long-term strength, stress-strain relationship, degradation, failure mode

CLC Number: