用于地基处理的生石灰密实块体膨胀性能的试验研究

On Expansion Properties of Lime Compacted Block for Foundation Treatment

研究了生石灰密实块体的膨胀性能,提出了通过植入膨胀材料挤密土体减小孔隙率来消除路基差异沉降的新的地基处理方法。试验研究结果表明:生石灰遇水立即反应、膨胀,过程可分为明显的前(较快)和后(较慢)两个阶段;增大成型压力和提高外加剂掺量都可以提高总膨胀率(膨胀量/初始体积);提高外加剂掺量可有效降低膨胀速率;工作压力增加,总膨胀率和膨胀速率均减小。当工作压力为400 k Pa时,生石灰密实块体的总膨胀率最大可达155%,膨胀过程时长可延至69小时以上。

In this paper, the expansion properties of lime compacted block is studied to propose a new method for foundation treatment by expanding material implantation, soil mass compaction, porosity reduction to control the differential settlement of subgrade. The test results show that the quick lime reacts and expands immediately in the present of the water. The process can be divided into two stages： early period （rapider） and late period （lower） ; the total expansion ratio may be improved with increase in forming pressure and the additive （swell increment/initial volume） ; the expansion speed may be effectively reduced with increase in the additive; the total expansion ratio and the expansion speed reduce with the increase in the working pressure. When the working pressure is 400 kPa, the total expansion ratio of the lime compacted blocks can be up to 155 % , while the expansion process can be extended to longer than 69 h.