Study On The Ratio Of Mud In The Peat Soil For The Mud Which Is Used To Protect Cast-in-place Pile

In this paper,the problem of the mud ratio of the mud-protected cast-in-place pile in peat soil is studied.Starting from the actual engineering background,t-he change law of bentonite mud in the presence of peaty soil medium is obtain-ed through experiments.It is found that the peaty soil medium has a positive effect on bentonite.The mud has a "weakening effect",and two measures are specifically adopted to solve this problem.One is to eliminate the adverse effects of mainly peaty soil on the mud,and to study the effects of wood carbon powder,coconut shell carbon powder,potassium hydroxide,sodium humate and other samples;the second is to improve additives and introduce new additives,to enhance the performance indicators of the mud;researched the different（Sichuan,Liaoning,etc.）bentonite and additive polyanionic cellulose and more than ten kinds of admixtures for different dosages and different organic content of peaty soil media.Through experiments about lots of programs and multiple measurements of some indicators during experiments combined with theoretical analysis of admixtures,the solution was finally selected（sodium polyacrylate,hydroxypropyl methylcellulose,sodium hydroxide solution）.And through the use of Design Expert software for response surface processing analysis,to explore the effect of admixtures on the mud and interactive effects,and combined with the SPSS statistical software to carry out an experimental analysis of the effect of the performance of the mud under the high content of peaty soil medium,Explore the feasibility of the plan;draw certain conclusions:（1）The presence of peaty soil media will increase the water loss of bentonite mud,decrease the colloid rate,and deteriorate the properties of the mud skin.The organic matter component is more,The “unfavorable effect” on the mud will be greater;the presence of high humic acid in the peaty soil affects the mechanism of the bentonite the mud and changes the acid-base environment of the mud,which is one of the main reasons for the decline in the performance of the mud One.（2）According to the characteristics of high organic matter content and high humicacid content in peaty soil,we selected coconut shell activated carbon,wooden activated carbon,sodium hydroxide and other substances to conduct multi-group experiments to try Reduce the adverse effects of humic acid in peaty soil.Through lots of experimental comparisons,analysis and verification,it was screened out that potassium hydroxide and sodium hydroxide solutions have a good effect on the improvement of the performance of the mud.（3）Aiming at the characteristics of bentonite mud under peaty soil,through the improvement of additives and the introduction of new additives,it can resist the adverse effect of peaty soil on the bentonite mud.Through the screening of more than ten kinds of additives such as sodium polyacrylate,a series of orthogonal experiments under the action of a factor was carried out to explore the effects of unequal contents on the mud in the peaty soil.The results show that sodium polyacrylate and hydroxypropyl methylcellulose as admixtures have good adaptability in peat soil compared to other admixtures.（4）For different organic peat soil media mud,three selected additives（sodium polyacrylate,hydroxypropyl methyl cellulose,sodium hydroxide solution）are used for analysis and improvement.And using Design Expert software response surface method to conduct multi-factor simulation experiment analysis for the three substances in these two methods,explore the influence of each factor on the mud index under the peat soil medium and the interactive influence.（5）The composition,impurities,treatment process and other factors of different bentonites in different places have an impact on the performance of the mud.The statistical software SPSS was used to assist in the analysis of the mud performance under the high peat soil content,and the ratio of the scheme was verified.feasibility.And analyze the many advantages of the new mud ratio scheme in terms of environmental protection,economy,and simplifying the construction process from the aspects of the nature of the additives and the working environment.