This work was on non-activated and activated lateritic soil used in proportions of 0%to 30%,to replace fine sand by wt.%,in the production of lateritic concrete.A mix of 1:2:4 was used,and the cube samples were cured...This work was on non-activated and activated lateritic soil used in proportions of 0%to 30%,to replace fine sand by wt.%,in the production of lateritic concrete.A mix of 1:2:4 was used,and the cube samples were cured in four(4)curing media of water,sand,polythene,and sawdust.The aim was to evaluate the effects of these curing methods on the mechanical strengths,and other properties of lateritic concrete.The sensitivity of the generated data was characterized statistically and developing linear regression models for predictions.For the Non-Activated Laterite soil(NALS,control mix(0%)),the design strength of 20 MPa was achieved by all the curing methods(standard and non-standard).However,for other replacement levels,water curing was adequate for 10%and 30%,sand at 10%,and sawdust for 20%and 30%,respectively.On the other hand,for the Activated Laterite soil(ALS),the 20 MPa design strength was met only at 0%replacement for all curing methods.Sawdust medium at 10%also satisfied the 20 MPa strength.展开更多
In order to prolong the working time of calcined flint clay-bauxite castables during construction at high temperature,boric acid was added into the castables. The effect of boric acid on working time and curing cold c...In order to prolong the working time of calcined flint clay-bauxite castables during construction at high temperature,boric acid was added into the castables. The effect of boric acid on working time and curing cold crushing strength of the castables at 25 ℃ and 35 ℃ were investigated. After 24 h curing in mould and another 24 h curing at 110 ℃ after demoulding,the specimens were heat treated at 1 000 ℃,1 300 ℃,and 1 500 ℃ for 3 h,respectively. The permanent linear change,bulk density,modulus of rupture,and cold crushing strength were determined. The result shows that there is no need to add boric acid when calcined flint clay-bauxite castables works at 25 ℃; when calcined flint clay-bauxite castables works at 35 ℃,boric acid can increase the working time of the castables,but decrease the curing cold crushing strength a little. Adding boric acid into calcined flint clay-bauxite castables doesn＇t worsen performance of the castables.展开更多
文摘This work was on non-activated and activated lateritic soil used in proportions of 0%to 30%,to replace fine sand by wt.%,in the production of lateritic concrete.A mix of 1:2:4 was used,and the cube samples were cured in four(4)curing media of water,sand,polythene,and sawdust.The aim was to evaluate the effects of these curing methods on the mechanical strengths,and other properties of lateritic concrete.The sensitivity of the generated data was characterized statistically and developing linear regression models for predictions.For the Non-Activated Laterite soil(NALS,control mix(0%)),the design strength of 20 MPa was achieved by all the curing methods(standard and non-standard).However,for other replacement levels,water curing was adequate for 10%and 30%,sand at 10%,and sawdust for 20%and 30%,respectively.On the other hand,for the Activated Laterite soil(ALS),the 20 MPa design strength was met only at 0%replacement for all curing methods.Sawdust medium at 10%also satisfied the 20 MPa strength.
文摘In order to prolong the working time of calcined flint clay-bauxite castables during construction at high temperature,boric acid was added into the castables. The effect of boric acid on working time and curing cold crushing strength of the castables at 25 ℃ and 35 ℃ were investigated. After 24 h curing in mould and another 24 h curing at 110 ℃ after demoulding,the specimens were heat treated at 1 000 ℃,1 300 ℃,and 1 500 ℃ for 3 h,respectively. The permanent linear change,bulk density,modulus of rupture,and cold crushing strength were determined. The result shows that there is no need to add boric acid when calcined flint clay-bauxite castables works at 25 ℃; when calcined flint clay-bauxite castables works at 35 ℃,boric acid can increase the working time of the castables,but decrease the curing cold crushing strength a little. Adding boric acid into calcined flint clay-bauxite castables doesn＇t worsen performance of the castables.
