| The ancient Pingyao Wall of Shanxi province is the most intact ancient county,it has been placed on the《International legacy content》in 6 December of 1997.The ancient Pingyao Wall had been serviced many times,however it also has many problems,such as surface airslake and unstable structure.The main reason of phenomenal is some clay included in soil,the hydrosphere percent changing of the soil including some clay result in expend with sop water or shrink with miss water.The second reason is that there are some problems of materials and technics existing in the old wall.The ancient wall's materials is soil and lime,and the lime's percent ia always 20-30%.What's more,the ancient technics is one flat soil and one flat lime,the technics lead the soil and lime mixing asymmetry. The aim of this study is,firstly,to solve the reinforce and protect problem of the soil wall.Firstly,both the historic soils from the ancient Pingyao Wall and the new soils from the soil deposits have been mineralogically and chemically studied.Base on the study and experience,we decided to add lime to the new soil. Although the method adding lime to soil has been existed thousands years, especially it has been used in building road broad.There are some researches show that the percent and kinds of lime is different by terrene,it is not the more lime percent,the more intensity.A ubiquity problem is that some project's lime percent adopt traditional 20-30%without any science researches. Peoples always think the more lime percent,the better.Reverse,overfull lime can not increase the intensity but reactive.Based on the problem and subject of expert,the thesis finish the following content:we ensure the quicklime percent by a series of researches,and discuss the influence of water percent and deposit time on the characteristics of improving soil.Considered the different of actual tamper and sample mould,we carry out the agin researches, in the research we adopt manual tamper,and we discuss the influence of additive on the characteristics of improving soil.At last,we test the structure of soil and improving soil by IR,XRD,SEM.The research shows that the structure of kaolinite has some change and there are some colloid in the structure.Based on the researches we discuss the improving mechanism.The thesis get the following conclusion:We made many kinds of directions of improved soil,then test their characteristics to improve directions.At the same time,we discuss the influence of conserve and deposit on the characteristic of improved soil. Finally,we find perfect direction and technics.On the basis of experimental results,the main mechanisms of improvement have been primarily discussed, the following conclusions can be drawn from the experimental results.1.The clay particles(＜2μm)of the new soils ranges from 15-16%, showing the new soils fall into the categories ST/TL according to the DIN 18196.2.Based on the influence of percent of quicklime on intensity and expend, we get the best percent of quicklime.3.Based on the influence of deposit time on intensity and expend,when the deposit time is 2 hours,we can get the biggest intensity and the most clam expend curve.4.Adding white lime,hemp and rice water to improved soil can improve the characteristics of improved soil,however,it is not actual to be used in engineering.5.the best direction is:3 percent quicklime,3 percent hydratable lime and 20 percent water.6.Conservation condition play an very important role in intensity,we can confirm the best conservation condition is to conserve in wettest condition 28 days,by the influence of conservation condition on characteristic of improved soil.7.The improving mechanism:the most of quicklime has react and turn to colloid calcium carbonate,there are few colloid calcium hydroxid between grain,and there are few colloid aluminate calcium and silicate calcium exist in the surface of grain.Colloid connected the grain lead to increase the intensity,enhance the water-resistant,weaken the dilatability...
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