Study On Durability Of Modified Raw Material

Raw soil construction is constructed from raw materials that have not been roasted,and has the characteristics of heat insulation,heat preservation,and humidity adjustment.However,due to the fatal defects of the material itself,raw soil construction itself has low strength and poor water resistance,which hinders raw soil.The application and promotion of materials,this topic through different methods of modification to study the effect of modification methods on raw material durability.In this paper,raw material is taken as the object of study.The change of the durability of the raw material after the modification of the raw material with cement and jute fibers is discussed.Provides data and theoretical basis for load performance,structural safety and stability of raw material and raw soil construction during service.research shows:(1)Under capillary water absorption: the unmodified raw soil capillary absorption coefficient was 0.090 g/cm2·min-1/2.After adding jute fiber,the water absorption increased by 43.2%,and the capillary absorption coefficient increased by 33.7%.After adding cement,the water absorption decreased by 35.3%,and the capillary absorption coefficient decreased by 19.8%.Under the environment of constant humidity,raw material's ability to hold water gradually weakens.(2)The compressive strength of the unmodified raw material before the freeze-thaw cycle reached 3.5 MPa,and the flexural strength was 0.90 MPa.After 30 freeze-thaw cycles,the compressive strength was 1.9 MPa and the flexural strength was 0.32 MPa.After cement modification,the compressive strength was increased to 10.6 MPa and the flexural strength was increased to 4.13 MPa.After 30 freeze-thaw cycles,the compressive strength was 9.6 MPa and the flexural strength was 3.85 MPa.When the cement modified raw soil after 7d carbonization compressive strength up to 11.6MPa,with the deepening of carbonization,the compressive strength of 28 d compressive strength is reduced to 10.4MPa.(3)The compressive strength and flexural strength of the unmodified raw material before and after the wet-dry cycle were 3.9 MPa and 0.99 MPa,respectively.After 30 cycles of dry-wet,the compressive strength and flexural strength were 3.2 MPa and0.33 MPa.After the jute fiber was modified,the compressive strength was reduced to 3.5MPa and the flexural strength was increased to 1.65 MPa.After 30 freeze-thaw cycles,the compressive strength was 4.9 MPa and the flexural strength was changed to 0.54 MPa.When jute-modified raw soil was sprayed with rainwater,collapse and strength instability occurred immediately.