海南省沿海地区分布着一种特殊的有机质浸染砂,单纯采用水泥作为固化剂的深层搅拌法不能有效提高其力学强度,因此选用不同材料做外掺剂对其进行了大量的固化试验.通过不同水泥、不同水泥掺入比、不同固化材料及其掺入比、不同水灰比和龄期下水泥土的无侧限抗压强度试验以及微观结构试验,研究了有机质浸染砂的最优固化材料及水泥土的配合比;分析了水泥土的力学行为、变化规律和加固机理,发现单纯采用水泥不能有效加固海湾相有机质浸染砂的原因是水泥的水解水化作用会发生延缓,以及砂颗粒与水解水化产物的作用受到阻碍,掺入适量的熟石灰可获得较好的加固效果.%There is a special kind of organic sand in the coastal regions of Hainan Province;the strength of the sand cannot be effectively improved by only using cement.A lot of experiments was done to improve the sand with cement and other different materials.Through microstructure test and the unconfined compressive strength test with different cement and its dosage,different materials and their content,different water cement ratio and curing time of cement soil,the best material and the mixture ratio are studied;the mechanical behavior,the change law and the reinforcement mechanism of cement-soil are analyzed.The results show that the reason of not effective improvement is the delay of the hydration of cement and the block of the interaction between sand particles and the hydration products.The better effect of reinforcement can be obtained by adding appropriate hydrated lime.
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