改性生土基砌块抗压抗折性能试验研究

Study on compressive and flexural properties of modified raw soil based blocks

为改善生土基砌块的抗压、抗折性能,分别选取水泥、石灰、纤维作为改性材料,采用单掺和复掺的方式,通过系列试验研究不同改性材料对生土基砌块抗压和抗折强度的影响,并用扫描电镜观察生土基砌块的微观结构。试验结果表明:单掺水泥、单掺石灰均能改善生土基砌块的抗压、抗折性能,但石灰改性效果不如水泥;在复掺10%水泥、5%石灰的改性生土基砌块中掺入1%的纤维,改性效果最佳。微观结构分析表明:水泥、石灰水化产生的水化产物填充于土颗粒之间,能够降低孔隙率,提高结构密实度,从而提高生土基砌块的抗压、抗折性能;纤维利用自身的韧性及加筋作用,通过增大纤维与土颗粒的摩擦力,进而提高生土基砌块的抗压、抗折性能。

In order to improve the compressive and flexural properties of the raw soil based block,cement,lime and fiber are selected as the modified materials in this paper,and the effects of different modified materials on the compressive and flexural strength of the raw soil based block are studied through a series of tests in the way of single mixing and multiple mixing,and the microstructure of the raw soil based block is observed with a scanning electron microscope.The test results show that both cement and lime can improve the compressive and flexural properties of raw soil based blocks,but the effect of lime modification is not as good as that of cement;Adding 1%fiber into the modified raw soil based block mixed with 10%cement and 5%lime has the best modification effect.The microstructure analysis shows that the hydration products produced by the hydration of cement and lime are filled between soil particles,which can reduce the porosity,improve the structural compactness,and thus improve the compressive and flexural properties of the raw soil based block;Fiber uses its toughness and reinforcement to increase the friction between fiber and soil particles,thereby improving the compressive and flexural properties of raw soil based blocks.