液相环境对水泥固化土抗压强度增长的影响

对于同种土样形成的固化土,水泥掺量增加到一定程度后单位水泥量产生的固化土抗压强度增量会显著提高;物理性质相近的土样掺加等量的水泥后固化土抗压强度有显著的差异.为解释上述试验现象,测定了相应固化土孔隙液中主要离子的浓度,并进行热力学计算.结果表明:水泥掺量较少时,固化土孔隙液中Ca(OH)₂不饱和,单位水泥量水化生成的胶凝性物质量较少,故产生的固化土抗压强度增量也较小;当土样中水泥掺量达到一定程度后,固化土孔隙液中Ca(OH)₂饱和,固化土中胶凝性物质能充分生成,单位水泥量产生的固化土抗压强度增量较大.物理性质相近的土样掺加相同的水泥量,固化土孔隙液中Ca(OH)₂离子浓度不同,故而固化土抗压强度也不同.

Effect of aqueous phase condition on the strength increasing of cement stabilized soil

The strength increment of stabilized soil generated by unit cement content would remarkably increase after cement content reached to a certain amount, and at same cement content there existed obviously strength difference between the stabilized soil samples formated from different soil samples with same physical characteristics.In order to find the reason of these experimental results,concentrations of main ions in the pore solutions squeezed from the stabilized soil samples were measured,and the concentrations of Ca(OH)_2 in the pore solutions with many ions were calculated by the thermodynamic method.The result shows that when cement content is not enough to ensure the Ca(OH)_2 reach to saturation,the gel generated by unit cement hydration is less,therefore the strength of the stabilized soil is lower;When cement content reaches to a certain amount,the concentration of Ca(OH)_2 in the pore solutions reaches to saturation,the gel can be sufficiently generated,therefore the strength increment of stabilized soil generated by unit cement content remarkably increases.At same cement content the concentrations of Ca(OH)_2 in the pore solutions are various,so there are strength difference between the stabilized soil samples with same physical characteristics.