Solidification and permeation combined testing device and method

Abstract

The invention provides a solidification and permeation combined testing device and method. The solidification and permeation combined testing device comprises a soil sample cabin for holding an experiment soil sample, wherein water-penetrating stones are arranged at the top end and the bottom end of the soil sample cabin; or the water-penetrating stone is arranged at one end of the soil sample cabin and a waterproof test block is arranged at the other end of the soil sample cabin; the each water-penetrating stone is provided with a pore water guide pipe communicated with the water-penetrating stone; the pore water guide pipe is provided with a pore water flow monitor; a sealing plug is arranged at the top of the soil sample cabin; the bottom of the soil sample cabin is fixedly arranged on a platform; a pressurizing device is arranged at the top of the soil sample cabin; the soil sample cabin is provided with a vertical stress sensor and a deformation sensor; the platform is provided with a sample chamber for holding the soil sample cabin; the pressurizing device comprises a counter weight block for providing pressure and a pull force frame which is used for pressurizing the soil sample cabin in the sample chamber and is arranged along the vertical direction; the sample chamber is fixedly arranged on the platform and an opening is formed in the top of the sample chamber; the first end of the pull force frame is connected with the counter weight block through a connection mechanism and the second end of the pull force frame sleeves the sample chamber to pressurize a test sample in the sample chamber.

Description

technical field [0001] The invention relates to the field of mechanical technology, in particular to a combination test device and method for consolidation and penetration. Background technique [0002] Consolidation-permeability joint test is suitable for providing soil compression and permeability test parameters for general construction projects to large-load projects, deep-buried projects, and ground subsidence projects at the same time. [0003] The effective stress on the soil is the total stress minus the pore water stress, that is, the effective stress σ'=total stress σ-pore water stress u. Under the action of effective stress in saturated soil, the pore water in the saturated soil will migrate and infiltrate, the pore water stress will gradually dissipate and the effective stress will be gradually transferred to the soil particles. This principle is the famous Terzaghi effective stress principle. This principle process shows that the seepage of saturated soil pore ...

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Problems solved by technology

In the past, during the consolidation test of saturated soil, although the soil sample also had pore water discharged, it may be due to various reasons such as the direct contact between the water discharged from the soil sample and the atmosphere, resulting in water evaporation and other reasons, so the amount of drainage was not tested. The bond test only provides the consolidation deformation parameters of the soil sample, and does not involve the penetration parameters; while the traditional penetration test is completed by the permeameter, and the conventional permeameter is divided into a constant head permeameter (suitable for sand samples) and a variable head permeameter ( Suitable for making soil samples) two types, the water head is generally 2.0m, which is the water head loss through the soil sample at a certain time and temperature to calculate the permeability parameters, not involving compression parameters, and the obtained permeability coefficient is matched with it Engineering (dam construction, flood control, etc.) has a certain guiding significance

However, the permeability coefficient provided for the compression project of the soil will have a large deviation (the provided permeability coefficient may generally be too large, because the size of the permeability coefficient is positively correlated with the size of the void ratio, and the void ratio of the soil will change during the compression process. gradually become smaller), some even differ by 2 orders of magnitude, but at present, geotechnical laboratories still use the permeability parameters provided by the traditional penetration test method, which brings great uncertainty to the corresponding actual engineering design, budget, etc., and may cause cause great economic loss

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