莱州湾早全新世高黏粒软土工程地质特征及岩相古地理

Engineering Geological Characteristics and Lithofacies Palaeogeography of Early Holocene Highviscosity Soft Soil in Laizhou Bay

摘要:

依据工程地质调查、土工试验、14C测年及古生物鉴定，从莱州湾滨海地区的早全新世高黏粒软土中识别出3种古地理沉积环境。分析发现，软土黏粒含量高、呈暗色调，属埋藏型。颗粒级配、压缩模量等物理力学指标差异则指示了同期异相沉积软土的工程地质特征。采取Q型聚类分析，将莱州湾早全新世高黏粒软土划分为下三角洲相沉积软土、潮平相沉积软土、湖沼相沉积软土。通过统计分析，掌握了滨海区软土工程地质特性，为合理选取土工试验参数提供沉积学依据，为合理利用天然地基提供参考。

Abstract:

According to engineering geological survey, geotechnical test, 14C dating and paleontological identification, three paleogeographic sedimentary environments have been identified from the early Holocene highviscous soft soil in the coastal area of Laizhou Bay. It is found that the clay content of soft soil is high and dark, which belongs to buried type. The differences in physical and mechanical indexes, such as particle gradation and compressive modulus indicate the engineering geological characteristics of heterogeneous sedimentary soft soil in the same period. Adopting Qtype cluster analysis, Holocene highviscosity soft soil in Laizhou Bay can be divided into three categories：sedimentary soft soil of lower delta facies, tidal flat facies and limnetic facies.Through statistical analysis, engineering geological characteristics of soft soil in the coastal area have been learned. It will provide a sedimentary basis for selecting geotechnical test parameters rationally, and some references for rational utilization of natural foundation.