高级检索

    杭州市地面沉降重点区土体压缩和固结特性研究——以试验孔HZ22J06为例

    Study on the compression and consolidation properties of soil in the key area of land subsidence in Hangzhou: a case study of test hole HZ22J06

    • 摘要: 开展土体压缩固结特性研究,从宏观上分析土体变形影响因素,是探究地面沉降成因的重要内容。文章以杭州市地面沉降重点区水文地质工程地质综合试验孔HZ22J06土样为研究对象,通过室内试验对土体的物理力学性质、压缩变形及固结特征进行分析研究。结果表明:试验孔土体各物理指标之间存在显著的相关性,土体含水率、土粒比重、孔隙比、塑性指数、液性指数和压缩系数等指标随深度的增加总体上呈现先增大后减小的趋势;土样压缩系数随压力的增大呈现减小的趋势,且浅部土样压缩系数高于深部土样;土体固结系数与渗透系数之间存在密切的关联性,相同压力下不同类型土样的固结系数大小变化符合粉土>粉质黏土>淤泥质粉质黏土>淤泥质黏土的规律,这与土体渗透系数大小变化规律相一致;试验孔大多数土样处于欠固结状态,在现有自重压力作用下会进一步固结压密,易引发地面沉降。研究成果可为杭州市地面沉降成因规律研究和风险防控提供科学依据。

       

      Abstract: To investigate the soil compression and consolidation properties and analyze the influencing factors of soil deformation from a macro perspective is an important aspect for exploring the causes of land subsidence. Taking soil samples from the hydrogeology and engineering geological comprehensive test hole HZ22J06 in the key area of land subsidence in Hangzhou as an example, and the physical properties, compression deformation and consolidation characteristics of the soil were analyzed and studied by indoor testing. The results reveal a significant correlation among the physical indexes of the soil in the test holes, and the parameters of water content, specific gravity of soil grains, void ratio, plasticity index, liquidity index and compression coefficient show an overall trend of first increasing and then decreasing with the increase of depth. The compression coefficient of the soil samples generally decreases with increasing pressure, with shallow samples having higher compression coefficients compared to deeper ones. Furthermore, there is a close correlation between the consolidation coefficient and hydraulic conductivity of soil. Under the same pressure, the variation of the consolidation coefficient of different types of soil samples follows the law of silt>silty clay>muddy silty clay>soft clay, which is consistent with the variation law of hydraulic conductivity. Additionally, most of the soil samples in the test holes are in an under-consolidated state, which may cause further consolidation and compaction, leading to land subsidence. The research results could provide scientific basis for the study of the causes of land subsidence and risk prevention and control in Hangzhou city.

       

    /

    返回文章
    返回