Research On The Curing Agent For Shallow Mucky Soil

Coastal urban development requires consolidation of mudflats and backfill soils,where the mucky soils in the foundations have high moisture content,high compressibility,and low strength.These characteristics of mucky soil have a great influence on the construction of the project,making it impossible for many machines to enter the site.The shallow reinforcement of mucky soil can effectively solve the problem of the approach of construction machinery in the early stage.The curing method is an efficient and economical treatment method.In this paper,based on the properties of mucky soil,combined with the reinforcement effect of various solidified materials,the curing agents suitable for the shallow layer of mucky soil reinforcement are selected and the corresponding additives are designed.And through the experimental analysis of the curing scheme of the reinforcement principle and applicability,given a convenient and efficient curing program,so as to achieve the purpose of high efficiency and economy.For this reason,this article mainly carried out the following work:(1)Based on the characteristics of high moisture content,high compressibility,and low strength of mucky soil,the reinforcement effect of various reinforcement materials on mucky soil was analyzed.On this basis,factors such as solidification effect and material price were comprehensively considered.Determined to use the combination of fly ash and quicklime as a basic curing agent,and the use of sodium silicate,calcium sulfate,calcium chloride as an additive to reinforce mucky soil.(2)The additive ratio test is designed using the mixture design method.After determining the amount of the basic curing agent and the ratio of fly ash and quicklime,the unconfined compressive strength of the solidified soil at different ages is taken as the response value,and the ratios of three additive components are taken as independent variables.After the test is designed,the result is obtained.Through the single factor effect analysis,interaction analysis and microscopic analysis,the formulation of additive TZ-01 is finally determined.(3)The response surface method is used to optimize the curing protocol.The unconfined compressive strength of the solidified soil at different ages is used as the response value,and the initial moisture content,organic matter content,ash content of the mucky soil and the ratio of TZ-01 are four independent variables.The strength regression equations for solidified soils under different ages are constructed.According to the results obtained from the tests,the effect of internal and external factors on the strength of solidified soil are analyzed from single factor effect analysis and interaction analysis.The test results show that this solidification scheme can effectively reinforce mucky soil and make its early strength meet the construction requirements.(4)According to the analysis of the response surface method test results,using the strength of the 7-day solidified soil as the reference value,tests are taken to establish a prediction model of the consolidated soil strength considering the age and various influencing factors.Through the obtained strength prediction model,according to the initial moisture content and organic matter content of the mucky soil in the site,the best curing ratio and the corresponding solidified soil strength can be obtained through calculation.Finally,through the cost analysis under different proportions of the curing agent,the economic suitability of the curing program is illustrated.