Experiment And Application Research On Factors To Influence Formation Of Lime-ash Soil Strength

Because of many merits, such as higher strength, better water stability, convenient for construction and good for environment protection, lime-ash soil is widely used now in high class highway sub-base. However, there are some difficulties in controlling lime-ash soil construction quality, especially the lime content, fewer researches are done to inspect lime content as well as lime content decaying in lime-ash soil and most inspections on the construction spot are based on lime-soil. On the basis of large numbers of indoor experiments, this paper studies a series of physical and chemical change laws of lime-ash soil along with the strength in the process of sealing and compactness when it is used to be highway sub-base or sub-grade. Moreover, this paper also does some experimental researches on the decaying condition of effective calcium and magnesium content in lime-ash soil as the strength increases under different water contents and different compactness conditions, which is very helpful for the inspection of effective calcium and magnesium content as well as the strength under different conditions and different periods.The experiments in this paper mainly include physical and mechanical properties of raw materials, standard compactness characters of lime-ash soil as well as the compressive strength change laws of lime-ash soil with different proportions. Meanwhile, this paper analyzes the lime content decaying in lime-ash soil and dry density change laws in the process of lime-ash soil strength forming under different ages, different conservation conditions and different compactness conditions, which has guiding meaning for the inspection of lime-ash soil strength under different conditions and different periods as well as effective calcium and magnesium content. The experimental research shows that the primary factor to influence early strength of lime-ash soil is lime-ash proportion, while the late strength is lime-ash content. Therefore, we should base on later age experimental results when we design the mixture composition. Under the standard conservation condition, the decaying of lime-ash soil is about 10% in the first seven days, 18% in fifteen days and 30% in thirty days. In addition, its dry density is almost the same in the first three days, about 1% to the seventh day and is not very obvious in later period.