Laboratory Study On Wheat Straw Fiber Cement Soil

The reinforcement and treatment of soft soil has been a major problem in geotechnical engineering field.Due to the influence of sea water,the Dongtai area of Jiangsu has accumulated a lot of thick soft clay,which forms a representative soft soil layer.The soil layer is mainly silt soil,and the ground resistance is poor,so it can not meet the requirements of construction.Therefore,cement is often used as curing agent in the project,and the soil is mixed together to form the cement soil with good mechanical properties.Because of its low cost and simple operation method,cement soil has a wide range of applications in foundation reinforcement,slope stability and subgrade engineering.In this paper,the soft soil in Dongtai area is taken as the experimental object.At the same time,the method of improving the mechanical properties of cement soil by adding wheat straw fiber into cement soil was discussed.The main research contents and results are as follows:(1)of soft soil in Dongtai area was solidified by cement,the Dongtai soft soil solidified the unconfined compressive test,considering the influence of the two factors of cement content and curing time on the strength of soil cement,also got cement soil stress-strain curve,can be read from the curve cement soil with cement content increased with the development direction of the trend to brittle.(2)the corrosion of wheat straw fiber in pH value solution with different pH value was studied.The mass loss rate and tensile test of wheat straw after corrosion were calculated.So we have a basic understanding of the mechanical properties of wheat straw fiber.The experimental results show that the corrosion mechanism of wheat straw is completely different from that of acidic and alkaline environments.(3)the optimal proportion of wheat straw fiber cement soil was obtained through a large number of experiments,and the optimal blending rate and the optimal reinforcement length were determined by the method of single variable control.The optimal ratio of straw was 0.1%,and the optimal mixing length was 5mm.(4)the cement soil and wheat straw cement soil are compared.It is proved that the incorporation of straw into the soil can improve the strength of cement soil and the ability to resist deformation,and can also reduce the brittleness of cement soil.