土力学0（Soil mechanics 0）.docVIP

土力学0（Soil mechanics 0） A: compression and settlement of soil will not be completed in a very short period of time, so the time related. Stress history of soil to soil has been in the history of the stress state and stress state changes. If the soil stress in the history had great pressure, for some reason the pressure decreases, the building in the soil, the soil under unloading and compression, the compression will be relatively lower. For most of the natural soil, due to a long geologic age, under the action of gravity has completed the consolidation, consolidation stress does not change, no longer cause soil caused by external compression, additional load only stress can make soil compression. Two: first through the upper structure basis for the transformation of contact stress, effect on the site, additional stress, consolidation through water and particulate hole drainage, exhaust in the process of consolidation, the additional stress into the effective stress. Three: stratified summation method: approximate as each layer of the soil in the uniform and uniform stress distribution along the thickness, the idea is that the layered foundation under natural conditions, determine the compression layer range, calculate the amount of compression stratified by the uniaxial compression formula, then the cumulative total settlement. The steps are: according to the characteristics of load on the foundation, calculation of base pressure and distribution; the layered foundation; calculation of weight in the ground stress distribution; calculation of the foundation in the vertical additional stress distribution; the average hierarchical average self weight stress and average additional stress for the i layer; compression; the layered compression accumulation, get the total settlement of the foundation. The foundation norms recommendation: Based on layered summation method, summarizes the construction project of our country a lot of settlement data, the average additional str