Experimental Study On Compaction Performance Of Soil Modified By Biomass Power Plant Ash And Nano-silic

As a by-product of biomass power generation,biomass power plant ash has been used in low-level utilization methods such as road construction and landfill in practice,and some are accumulated or treated as waste.Studies have shown that the types of elements involved in biomass power plant ash can be used as a material for soil improvement,to achieve the purpose of modifying soil,and then to improve the properties of engineering fill.In this paper,the embankment filling soil from Tonghe County,Heilongjiang Province was used to simulate embankment filling indoors,and the modification of biomass power plant and nano-Si O₂ was studied.The proportion of modified soil mixed with power plant ash is 10%,15%,20%,25%,30%,and mixed with nano-Si O₂ 0.5%,1.0%,1.5%,2.0%and 2.5%.A series of tests were carried out on the modified soil:natural moisture content test,liquid plastic limit test,particle analysis test,compaction test,unconfined compressive strength test,SDG densitometer test,ring knife test,etc.The main work and research conclusions are as follows:（1）Biomass power plant ash and nano-Si O₂ have significant effects on the basic physical properties of soil samples.The non-uniformity coefficient of the modified soil sample has a decreasing trend,and its liquid limit and plastic index are also decreasing,but the plastic limit has little change.With the proportion of materials such as biomass power plant ash added to the soil sample changing,the optimum moisture content of the modified soil is also changing,showing a decreasing trend.（2）The unconfined compressive strength of the modified soil samples increases first and then decreases with the change of the dosage.（3）In the laboratory,the compaction test method is used to restore the embankment filling construction site.According to the pre-set amount of modifier,the SDG soil densimeter non-destructive testing is suitable for this kind of modified soil.（4）The optimum dosage of biomass power plant ash and nano-Si O₂ particles are20%and 1.5%respectively,and the properties of modified soil after adding nano-Si O₂are better than those under the optimum dosage.