石灰改性膨胀土击实曲线的双峰特性研究  

Bimodal characters of compaction curve of lime treated expansive soil

作　　者：程钰 石名磊[3] 

机构地区：[1]高速公路养护技术交通行业重点实验室,济南250031 [2]山东省道路结构与材料重文实验室,济南250031 [3]东南大学岩土工程研究所,南京210096

出　　处：《岩土力学》2011年第4期979-983,共5页Rock and Soil Mechanics

摘　　要：膨胀土掺石灰改性之后,其粉粒组的含量显著增加。当采用湿法击实时,由于土体保持了原有的结构性并表现出粉土的特性,在某个较低含水率时,击实功没有超过破坏其结构性的程度,出现一个干密度峰值。随着含水率的增加,击实功破坏了土的结构性,土体重新压实,曲线出现了另一个大干密度的峰值。因此,击实曲线表现出不稳定的双峰现象,从而降低了击实曲线的实用性及可靠性。然而采用修正湿法得到的击实标准,相对于湿法更加合理,相对于干法更加实用可靠,为工程施工质量控制与路基工后质量评价提供了更加有效的方法。Silt content increases significantly during the experiments of lime treated expansive soil. When the wet method is adopted,the soil maintains original structure and performances of silt features. If the water content at a lower level, the compaction power is lower than the structural damage and the compaction curve shows a dry density peak. With the increasing of water content, compaction power exceeds the structural damage and the compaction curve shows another dry density peak. Therefore, the compaction curves show instable bimodal phenomenon, which reduces the practicality and reliability of the compaction curves. However, the modified wet method is adopted to overcome the shortcomings of both wet method and dry method. The results provide an effective method for quality control of construction and quality evaluation of completion.

关 键 词：膨胀土 消石灰 击实曲线 石灰改性 

分 类 号：TU443[建筑科学—岩土工程]