Experimental Study On The Properties And Mechanism Of Solidified Saline Soil In Inshore With SH Agent And Lime For Construction Of Road Embankment

There is a lot of saline soil in the west land of Bohai gulf, in usually saline soil should be solidified before using for engineering construction. Take the road embankment of highway for an example, the solidified saline soil with lime is prone to absorb water and lose some strength. A great quantity of previous research results in laboratory have demonstrated that mixing the SH agent into solidified soil with lime can effectively increase the strength and obviously improve the water stabilization. The in-situ compaction test was carried out in the important place of coastal highway located in Fengnan country of Hebei province (the percentage of easily dissolved saline is 3.87),which principally studied the suitability of applying previous research results in laboratory to the practice; and the experiments in laboratory were tested with same saline soil and same solidifying materials during the same period, in which the mechanism of SH agent was explored; meanwhile the influencing factors to the effect of solidified soil with SH agent and lime were analyzed in this thesis. Main research contents and results are as follows:(1)Took the typical section of coastal highway located in Fengnan country of Hebei province as experimental road, on which the in-situ compaction test of solidified soil with lime and SH agent + lime were carried out. When the curing periods of experimental road embankment were one, two, three and four weeks, such tests as the compression strength of the big piece of soil models, shear strength, compression and permeability were done in laboratory, and all experimental samples came from the site of experimental road. It has been indicated that the water stability of solidified soil is improved, the strength and distorted resistance is increased by mixing SH agent into the solidified soil with lime.(2)After curing period of six weeks of the experimental road, the Degree of compaction, California Bearing Ratio, rebound modulus, deflection value of compacted soil were inspected in site. It has demonstrated that these parameters of solidified soil with SH agent that have met the requirements of road embankment of highway, it is better than those with lime only.(3)The experiments in laboratory of solidified soil with lime and SH agent +lime were done with same saline soil and same solidifying material during the same period of the test in site, which included California Bearing Ratio test, unconfined compression strength test, pull strength test, triaxial compression test, compression test and permeability test. It has revealed that SH agent can improve the strength of solidified soil and decrease the abilities of permeated and distorted, which is identical with the results of compaction test in site.(4)In order to research the solidifying mechanism of SH agent, the microstructure pictures of solidified soil with lime and SH agent + lime were taken by using SEM, and Leica QWin5000 was used to treat these pictures. It has been certified that SH agent encloses soil particles and makes the connection like fishing net between particles and in void, which increases the strength and improves the precluding water.(5)Based on the previous experiments in laboratory, the compaction test in site and the experiments in the same period of compaction test, the influencing factors of the effect of solidified soil with SH agent+lime have been analyzed.