珊瑚礁软土的工程性质  

Engineering properties of coral reef soft-soil

作　　者：秦志光[1] QIN Zhi-guang(CCCC Key Laboratory of Environment Protection&Safety in Foundation Engineering of Transportation,CCCC Fourth Harbor Engineering Institute Co.,Ltd.,Guangzhou 510230,China)

机构地区：[1]中交四航工程研究院有限公司,中交交通基础工程环保与安全重点实验室,广东广州510230

出　　处：《水运工程》2022年第12期232-238,244,共8页Port & Waterway Engineering

摘　　要：针对沙特阿拉伯Tusdeer港口珊瑚礁软土,结合区域地质特征,分析软土的形成原因,并根据室内试验、原位十字板试验等结果确定其工程性质。结果表明:珊瑚礁软土的形成具有区域性特征,平缓、呈锯齿状的泻湖浅盆地貌利于细颗粒的沉积,软土的分布往往不连续且规模相对较小,软土的钙质含量较高但存在区域性差异;珊瑚礁软土中粉粒含量为56%~79%,其工程性质与一般滨海、河湖软土存在较大差异;珊瑚礁软土黏聚力为2~5 kPa,低于滨海、三角洲软土,内摩擦角22°~31°,高于滨海、三角洲一般软土;在深度2~5 m,珊瑚礁软土原位十字板强度20 kPa左右,灵敏度为1.5,属于低灵敏软土;珊瑚礁软土为工程性质不良的土体,对工程具有危害性,应充分考虑珊瑚礁场地钙质软土存在的可能性及影响,慎重评价珊瑚礁工程场地的复杂程度。Regarding the coral reef soft-soil at Tusdeer Port in Saudi Arabia,this paper analyzes the formation causes of coral reef soft-soil combining with the regional geological characteristics,and determines the engineering properties according to the results of laboratory test and in-situ cross plate test.The results show that the formation of coral reef soft-soil has regional characteristics.The gentle and serrated lagoon shallow basin landform are conducive to the deposition of fine particles.The distribution of soft soil is often discontinuous and relatively small scale.The carbonate content of soft soil is high,but there are regional differences.The proportion of silt in coral reef soft-soil is 56%to 79%,and characteristic properties of this soil are quite different from those of general coastal soft soil,river or lake soft soil.The cohesive force of coral reef soft-soil is 2 kPa to 5 kPa,which is lower than that of coast and delta soft soil,and the internal friction angle is 22°to 31°,which is higher than that of coast and delta soft soil.In the range of depth from 2 m to 5 m,the strength of in-situ vane of coral reef soft-soil is about 20 kPa,and the sensitivity is 1.5,which belongs to low sensitive soft soil.The coral reef soft-soil has poor engineering properties,which are harmful to the project.The adverse influence of coral reef soft-soil site on project should be fully considered,and the complexity of geologic conditions should be carefully evaluated.

关 键 词：珊瑚礁 钙质土 珊瑚礁软土 工程性质 

分 类 号：U655.54[交通运输工程—港口、海岸及近海工程]