ISO/TS 17892-5:2004 土工技术研究和试验 土壤的实验室试验-第5部分： 加载渗压仪试验

标准编号：ISO/TS 17892-5:2004

中文名称：土工技术研究和试验 土壤的实验室试验-第5部分： 加载渗压仪试验

英文名称：Geotechnical investigation and testing — Laboratory testing of soil — Part 5: Incremental loading oedometer test

发布日期：2004-10

标准范围

ISO/TS 17892-5:2004旨在测定土壤的压缩、膨胀和固结特性。圆柱形试样受到侧向限制，承受垂直轴向加载或卸载的离散增量，并允许从顶部和底部表面轴向排水。固结仪试验得出的主要参数与土壤的压缩性和初始固结速率有关。有时还可以获得预固结压力、二次压缩速率和膨胀特性的估计值。在未扰动样品上进行的固结仪试验得出的主要参数如下:1） 压缩性参数；2） 固结系数；3） 表观先期固结压力或屈服应力；4） 二次压缩系数；5） 膨胀参数。增量加载固结仪试验的基本原理包括:应力路径对应于一维应变；排水是单向的和轴向的。地基中的应力路径和排水条件通常是三维的，沉降量和沉降率的计算值可能会出现差异。样本的小尺寸通常不能充分代表天然土壤中的组构特征。固结试验分析通常基于土壤饱和的假设。对于非饱和土，一些导出的参数可能没有物理意义。

ISO/TS 17892-5:2004 is intended for determination of the compression, swelling and consolidation properties of soils. The cylindrical test specimen is confined laterally, is subjected to discrete increments of vertical axial loading or unloading and is allowed to drain axially from the top and bottom surfaces.The main parameters derived from the oedometer test relate to the compressibility and rate of primary consolidation of the soil. Estimates of preconsolidation pressure, rate of secondary compression, and swelling characteristics are sometimes also obtainable.The main parameters which can be derived from the oedometer test carried out on undisturbed samples are:1) compressibility parameters;2) coefficient of consolidation;3) apparent preconsolidation pressure or yield stress;4) coefficient of secondary compression;5) swelling parameters.The fundamentals of the incremental loading oedometer test include: stress path corresponds to one-dimensional straining; drainage is one-dimensional and axial.The stress paths and drainage conditions in foundations are generally three dimensional and differences can occur in the calculated values of both the magnitude and the rate of settlement.The small size of the specimen generally does not adequately represent the fabric features present in natural soils.Analysis of consolidation tests is generally based on the assumption that the soil is saturated. In case of unsaturated soils, some of the derived parameters may have no physical meaning.

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