Research On Interaction Simulation Experiment Of Foundation And Basis During The Humidifying In Mine

The initial contact status of foundation and basis was changed by surface deformation in mining, which influences the upper buildings safety. Using the foundation improvement deformation characteristics during humidifying, make the local foundation softening, improve the contact status of foundation and basis, can achieve the purpose to protect the upper buildings.Self-design and produce the multifunctional mining deformation similar simulation test platform, it possesses simulation surface curvature deformation and compression deformation, realizing the local foundation humidification, rock movement in repeated mining, different angle coal mining and other functions.Using the multifunctional test platform finished simulation test of different surface curvature deformation, obtained the subgrade reaction change law during the surface curvature deformation. The results showed that: with the increase of the surface curvature deformation, the subgrade reaction distortion is more serious.When positive curvature deformation is 0.7mm/m2, local subgrade reaction increases from 0.01 Mpa at initial status to 0.07Mpa; when negative curvature deformation is 0.7mm/m2, local subgrade reaction increases from 0.02 Mpa to 0.11 Mpa. After surface occures curvature deformation, generated uneven subgrade reaction will seriously influence the safety of upper structure.On the basis of surface curvature deformation, completed the local foundation water injection humidifying test, obtained the subgrade reaction change law during the humidifying. The results showed that: with the increase of water injection, the distorted subgrade reaction gets greater improvement. When positive curvature deformation is 0.7mm/m2, local maximal subgrade reaction decreases from 0.07 Mpa to 0.01 Mpa after water injection 7.5758 L in the middle of foundation; when negative curvature deformation is 0.7mm/m2, local maximal subgrade reaction decreases from 0.11 Mpa to 0.04 Mpa after water injection 11.558 L in the both ends of basis.When surface occures curvature deformation, water injection in the serious distortion region of subgrade reaction, improve the contact status of foundation and basis, can reduce the uneven subgrade reaction and improve safety factor of the building.The wall maximum settlement is 21.4mm during the humidifying, doesn't cause collapse and instability of the foundation, the moisture content maximum difference is 6.29% after humidifying, the local soil void ratio has declined, the foundation bearing capacity was improved, the results showed that using the local foundation softening to improve the uneven subgrade reaction was caused by surface deformation is feasible.Based on the double-medium model, establish the relationship between average stress-strain and water injection rate of foundation humidifying, applying the layer summation method of calculation foundation settlement, derived from the estimate formula of foundation settlement after humidifying, and analyzed the observed and theoretical values of foundation settlement.