Foundation pit dynamic rainfall indoor model testing method and device under condition of multiple water-bearing layers

Abstract

The invention discloses a foundation pit dynamic rainfall indoor model testing method and device under the condition of multiple water-bearing layers. Through the arrangement of layered water supply interlayers and connection with a water tank capable of ascending and descending and pressure adjustable pressurizing pumps, stable, uniform and differential water power supply is provided for the water-bearing layers in the rainfall model test, accordingly, layering simulation for different pressure bearing water layer and phreatic layer hydrologic conditions on the site is achieved, the water tank position, the pressurizing pump pressure and the water suction pump rotation speed are dynamically adjusted in the rainfall process, a stable boundary water head of each water-bearing layer is maintained, and the model pit interior water level is controlled. A water level observation system is composed of a PVC observation pipe well, a water level indicator inductor and a water level digital display instrument, a water suction system is composed of a PVC water suction pipe well, water suction pumps and a flow meter, the water suction flow is dynamically controlled, and the water level and water suction flow changes inside and outside a test foundation pit in the rainfall process are monitored in real time. The parameter influence rule in foundation pit rainfall is explored through adjustment on the waterproof curtain obstruction ratio, the water suction pipe filter pipe length, position and other parameters.

Description

technical field [0001] The invention relates to the field of foundation pit dewatering engineering, in particular to an indoor model test method and device for foundation pit dynamic dewatering under the condition of multiple aquifers. Background technique [0002] As the development and utilization of urban underground space has become the trend of modern construction, some areas require large-scale precipitation during the excavation of foundation pits due to the abundance of groundwater hydraulics. Therefore, optimizing precipitation projects to improve precipitation efficiency, reduce precipitation costs and reduce precipitation The impact on the environment has become a hot issue in engineering construction at this stage. [0003] At present, there are more and more researches on indoor foundation pit dewatering model tests. For example, Tang Yiqun et al. designed a scaled-down precipitation model test to conduct a three-dimensional scaled-down simulation of the foundat...

AI Technical Summary

Problems solved by technology

[0004] The water supply of existing foundation pit dewatering model tests mostly adopts water tanks and model boxes directly connected to irrigation or setting model boundary water supply interlayers and water tank infiltration methods. This type of water supply can only provide a single water head for the model box and can only be used for a single Simulation of aquifer boundaries or boundary water supply that provides the same hydraulic pressure to different aquifers, but cannot meet the differential water supply of multiple aquifers

However, the stratum conditions at the site are relatively complex, and the boundary water head, hydraulic recharge, and seepage velocity of each layer of aquifer are different during precipitation. The need for simulation of hydrological conditions, and the existing experiments cannot realize the differential water supply of multiple aquifers

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