基于强度试验的五轴水泥土搅拌桩新技术研究

针对中国国内水泥土搅拌桩施工工艺存在的问题,研究开发了五轴水泥土搅拌桩新技术。该技术在施工过程中具有机械化程度高、成本低、工期短、环境污染少等特点,为了分析五轴搅拌桩加固软土地基以及基坑围护中的处理效果,在同一场地进行了五轴水泥土搅拌桩和二轴、三轴水泥土搅拌桩取芯检测和室内无侧限抗压强度试验。试验结果表明,在各土层中,三轴水泥土搅拌桩的桩身强度值较低,且离散性较大,二轴水泥土搅拌桩的强度较好,但不同龄期的强度值离散性变化较大,而五轴水泥土搅拌桩的强度值最高,离散性也较小,具有良好的推广和应用前景。

Experimental research on strength of five-axis cement-soil mixed piles

Based on a review of disadvantages of the construction techniques for cement-soil mixed piles in China, a new construction method called five-axis mixed pile method is developed. This new method has low cost, environmental pollution, short construction period and high efficiency. In order to investigate the improvement effect of five-axis mixed piles for soft ground in excavation engineering, comparison tests between five-axis mixed piles and biaxial, triaxial mixed piles are conducted in the same geological field. Through the unconfined compression tests on coring samples taken from cement-soil mixed piles, the test results show that the strength of the triaxial mixed piles is low and much more discrete, the strength of the biaxial mixed piles is better in every layer, but the discreteness of strength values greatly changes at different ages. However, the five-axis mixed piles with higher strength and low discrete behavior may have a good population and application value in the future.