EXPERIMENTAL STUDY ON EARLY STRENGTH OF NEW POLYMER SOLIDIFIED HIGH WATER CONTENT SILTY SOIL

Based on the traditional solidifying materials, a new polymer material was introduced in this paper. As for the insufficient early strength of solidified high water content silty soil and practical engineering applicability problems, a series of soil tests were carried out under two working conditions of in-site filling and off-site filling. The influence of environmental factors, dosage of curing agent and initial water content on the early strength of solidified silty soil were studied, and the optimal dosage of curing agent was determined. The damage property of solidified silty soil was analyzed by one-dimensional compressive stress-strain curve. The microstructure of solidified soil was analyzed by SEM, and the solidification mechanism of curing agent was explored. The test results show that the new polymer curing agent has a good curing effect on high water content silt. The optimal dosage of curing agent is 5%, and the unconfined compressive strength of cured silt soil can reach 2.4MPa for 7 days. The off-site filling conditions were more conducive to the strength development of solidified soil, which increased by about 30% compared with in-situ filling. Brittle failure occurs when solidified soil reaches ultimate strength, which should be avoided in engineering use. By analyzing the microstructure of solidified silty soil, it shows that the strength of solidified silt mainly comes from the agglomeration of soil particles with polar ions and the cementation of soil particles by the chain network structure formed by the hydration of high polymer.