Research Of Basic Properties And Pore Structure Of Foamed Mixture Lightweight Soil

A new light in recent years in the development of civil engineering in the field of filling material is foamed mixture lightweight soil,with its many characteristics,will be used for foamed mixture lightweight soil backfill soil or reducing load,can solve the shortage of land resources(such as the Pearl River Delta region),geological condition is not good(and soft soil permafrost area),covers an area of over(such as high embankment,settlement)is too large(bump,old road widening embankment frost)etc..In this paper,the use of botanical composite foaming agent with Shenyang clay as raw material,starting from the concept of foamed mixture lightweight soil,composition,and its preparation process of foam material analysis,prepared dry density in the 8?12KN/m3 foamed mixture lightweight soil,this paper made the following research on foamed mixture lightweight soil light soil gas:(1)The flexible use of experimental design method(uniform design method and orthogonal design method)is used to discuss the mix ratio.combined with multivariate nonlinear regression method of wet bulk density and fluidity of the regression equation,the orthogonal test and the variance analysis,finally the experimental results showed that the optimal foamed mixture lightweight soil mixing ratio is:cement dosage of 280kg/m3,dosage of raw soil 260kg/m3,bubble group the amount of 630L/m3,water cement ratio of 0.76.(2)On the basis of indoor test,the basic properties of air foamed mixture lightweight soil were studied.The effects of the types of raw soil(clay and river sand)and the amount of mixing on the strength are analyzed.The foamed mixture lightweight soil belongs to brittle failure and the compression strain is about 4.5%.The compressive strength of 28d under the same dosage of the same foaming agent is 2.56 times of the compressive strength of 7d,and the greater the cement model,the higher the strength.The foaming agent dosage on the bulk density,water absorption and anti impact properties were investigated,the foamed mixture lightweight soil has light intensity,easy to adjust,and the water absorption rate of slow growth in the 20d,110d absorption rate below 18%,and the shock resistance is 2.2 times that of cement stabilized soil,with low elastic damping good effect.(3)The pore structure of foamed mixture lightweight soil was studied.Scanning electron microscope was used to observe the microstructure of 1 kinds of cement stabilized soil and 4 different components of foamed mixture lightweight soil.The strength mechanism and hydration products of foamed mixture lightweight soil were analyzed.The porosity,average pore size and pore size distribution of the foamed mixture lightweight soil were obtained by Image-pro plus software.The influence of macropore structure parameters on the basic performance of the lightweight aggregate soil was analyzed.Under the same raw material,the larger the porosity,the smaller the density,the lower the compressive strength,the higher the water absorbability and the better the impact resistance.Based on that,the future development of this technology is evaluated and prospected,which is of great guiding significance for further research,application and popularization of foamed mixture lightweight soil in the future.