The loading system of in testing laboratory, soil pressure being simulated and analogy method
Technical field
What the present invention relates to is loading system and the analogy method that in testing laboratory, the native medium to vast scale preloading carries out level and come to loading the pressure layer distributed situation of native medium in simulating reality.
Background technology
In the process of civil engineering construction, usually to study the pressure distribution in native medium, in many engineerings, need the problem of solution all relevant with the pressure distribution in soil layer, such as stability of slope problem, mutual effect of the pile and soil problem and bearing capacity of pile foundation problem etc.But at present common research means is for to study by small-scale model test, but in the time there is native medium in the object of simulation, gravity becomes a physical quantity that is relatively difficult to simulation, and gravity is Fundamentals that cause the soil body and structure stress deformation and failure, its consolidation settlement, soil lateral pressure to structure etc. are all directly produced by gravity.This is difficult to simulation in the model test of small scale, and this just needs the native medium of vast scale as subjects, and vast scale rock-soil layer load application is carried out to soil pressure simulation.
At present domesticly load the commonly model test of small scale about soil pressure and load soil pressure, there is not yet vast scale rock soil medium is carried out to soil pressure simulation loading.
Summary of the invention
The technical problem to be solved in the present invention is to provide loading system and an analogy method that is enclosed within the native medium to vast scale preloading in testing laboratory and carries out level and come to loading the pressure layer distributed situation in native medium in simulating reality.
In order to address the above problem, the invention provides the loading system of in a kind of testing laboratory, soil pressure being simulated, described loading system is arranged in a test pit, in described test pit, be provided with test soil, described loading system comprises loading actuator, one end of described loading actuator is arranged in actuator mounting seat, described actuator mounting seat is arranged on the wall of described test pit, vertically Multi-layers distributing of described loading actuator, every layer loads actuator is that along continuous straight runs is equally distributed multiple, the other end of described loading actuator is connected with the rear side of the horizontal loading beam that can seesaw by transmission rod, described horizontal loading beam vertically Multi-layers distributing forms soil pressure loading surface, the number of plies of described horizontal loading beam is identical with the number of plies that loads actuator, all corresponding with the each soil layer in test soil, the front of described horizontal loading beam is described test soil.
Preferably, described test pit is a rectangle test pit, and described actuator mounting seat is arranged on the minor face wall of described test pit.
Preferably, also comprise that chute is installed in side and chute is installed in bottom surface, described soil pressure loading surface can be installed along side by chute and bottom surface installation chute seesaws.
Preferably, also comprise guide piece, described guide piece is arranged on the rear side of horizontal loading beam, and described guide piece comprises guide rail and orienting lug, described orienting lug and guide rail relative sliding.
Preferably, the rear of described horizontal loading beam is provided with body of wall with holes, and described transmission rod is connected with horizontal loading beam through body of wall with holes.
The present invention also provides the loading method of in a kind of testing laboratory, passive earth pressure being simulated, and it comprises the following steps:
1) the test soil that preloading need to be simulated in test pit, in preloading process, guarantees that the position of soil pressure loading surface is not promoted by test soil;
2) after described test mound has carried, on a soil layer of needs simulation, pressure transducer is set, the loading actuator that described soil layer is corresponding increases load gradually, loading beam that described soil layer is corresponding is travelled forward and promote described soil layer, until the distortion of described soil layer is excessive and destroy;
3) passive earth pressure while obtaining this soil layer destruction by described pressure transducer;
4) return to step 1), repeating step 1) to 3), obtain the passive earth pressure while needing another soil layer of simulation to destroy.
Preferably, in step 1), described soil pressure loading surface rear is provided with bracket and knee wall, and soil pressure loading surface is provided support, and is not promoted by test soil with the position that guarantees soil pressure loading surface.
Preferably, in step 1), in preloading process, the load that loads actuator by increasing gradually is not promoted by test soil with the position that guarantees soil pressure loading surface.
The present invention also provides the loading method of in a kind of testing laboratory, active earth pressure being simulated, and it comprises the following steps:
1) will load actuator and release certain distance, the test soil that then progressively preloading need to be simulated in test pit, in preloading process, increases gradually each layer of load that loads actuator and is not promoted by soil layer with the position that guarantees soil pressure loading surface;
2) after described test mound has carried, on a soil layer of needs simulation, pressure transducer is set, the loading actuator that described soil layer is corresponding reduces load gradually, and the loading beam that described soil layer is corresponding is promoted backward by described soil layer, destroys until the distortion of described soil layer is excessive;
3) active earth pressure while obtaining this soil layer destruction by described pressure transducer;
4) return to step 1), repeating step 1) to 3), obtain the active earth pressure while needing another soil layer of simulation to destroy.
The loading system of in testing laboratory provided by the invention, soil pressure being simulated and analogy method, using the native medium of vast scale as subjects, and vast scale rock-soil layer load application is simulated, can obtain passive earth pressure and the active earth pressure of each soil layer in test soil, its analog result is the truth of soil layer pressure in vast scale soil medium in reality more.
Accompanying drawing explanation
Fig. 1 is the perspective view of loading system of the present invention.
Fig. 2 is the vertical view of Fig. 1.
Fig. 3 is that the present invention removes the system side view after test pit body of wall.
Fig. 4 is that the present invention does not place dock structure and when soil test is cut the axonometric drawing after the body of wall of side open.
Fig. 5 is the schematic diagram of guide piece in the present invention.
Fig. 6 is the structural representation that the present invention includes the loading system of body of wall with holes.
Embodiment
As Fig. 1, Fig. 2, the loading system of in testing laboratory shown in Fig. 3 and Fig. 4, soil pressure being simulated, this loading system is arranged on a long 15m, wide 10m, in the rectangle test pit 1 of dark 7m, in rectangle test pit 1, be provided with test soil 2, loading system comprises loading actuator 3, be used for imposed load, the one end that loads actuator 3 is arranged in actuator mounting seat 4, actuator mounting seat 4 is arranged on the minor face wall of rectangle test pit 1, load vertically Multi-layers distributing of actuator 3, being used for the soil pressure of each soil layer in simulation test soil distributes, every layer loads actuator is that along continuous straight runs is equally distributed multiple, the other end that loads actuator 3 is connected with the rear side of the horizontal loading beam 6 that can seesaw by transmission rod 5, horizontal loading beam 6 vertically Multi-layers distributing forms soil pressure loading surface 7, the number of plies of horizontal loading beam 6 is identical with the number of plies that loads actuator 3, all corresponding with the each soil layer in test soil 2, the front of horizontal loading beam 6 is test soil 2.
More preferably, as shown in Figure 6, the rear of the horizontal loading beam 6 of this system is provided with body of wall 14 with holes, and transmission rod 5 is connected with horizontal loading beam 6 through body of wall 14 with holes, and the water that body of wall 14 with holes can intercept in test pit 1 enters actuator region.
The passive earth pressure that if the pressure being subject to due to each soil layer of test in soil is greater than it while destroying, this soil layer will produce destruction, therefore test the pressure size of the soil layer of lab simulation, passive earth pressure can not exceed its destruction time, therefore the passive earth pressure when maximum load ability of every layer of loading actuator can be destroyed according to every layer of soil layer calculates.
This loading system also comprises that chute 8 is installed in side and chute 9 is installed on ground, in the time that loading system is worked, soil pressure loading surface 7 can be installed along side by chute 8 and bottom surface installation chute 9 seesaws, and to test soil 2 load applications in loading beam 6 fronts, carrys out the soil pressure that the each soil layer of simulated field is subject to.
As shown in Figure 1, Figure 2 with shown in Fig. 5, for guaranteeing that the loading beam 6 of Multi-layer design is in the process seesawing, between levels, loading beam 6 can not rotate and be offset because of unbalance stress, at the rear side installation and guide device 10 of loading beam 6, guide piece 10 comprises guide rail 11 and orienting lug 12, orienting lug 12 and guide rail 11 relative slidings.
Utilize above loading system, the present invention also provides the loading method of in a kind of testing laboratory, passive earth pressure being simulated, and it comprises the following steps:
1) the test soil 2 that need to simulate in the interior preloading of test pit 1, in preloading process, soil pressure loading surface 7 rears are provided with bracket and knee wall 15, and soil pressure loading surface 7 is provided support, and are not promoted by test soil 2 with the position that guarantees soil pressure loading surface 7; Or the load that loads actuator 3 by increasing gradually is not promoted by test soil 2 with the position that guarantees soil pressure loading surface 7;
2) after native 2 preloadings of test complete, on a soil layer of needs simulation, pressure transducer is set, the loading actuator 3 that this soil layer is corresponding increases load gradually, loading beam 6 that this soil layer is corresponding is travelled forward and promote this soil layer, destroy until this soil layer distortion is excessive, in this process, the power that soil pressure loading surface 7 produces this soil layer is exactly the passive earth pressure of this soil layer;
3) passive earth pressure while obtaining this soil layer destruction by above-mentioned pressure transducer;
4) return to step 1), repeating step 1) to 3), obtain the passive earth pressure while needing another soil layer of simulation to destroy.
By above method, can obtain the passive earth pressure of each soil layer in test soil, and according to the displacement of loading beam corresponding to each soil layer, obtain the deflection of each soil layer, and then study the relation between passive earth pressure and the soil layer deflection of each soil layer.
Utilize above loading system, the present invention also provides the loading method of in a kind of testing laboratory, active earth pressure being simulated, and it comprises the following steps:
1) will load actuator and release certain distance, the each layer of distance that loading beam can retreat when this distance must guarantee each soil layer destruction, then the 1 test soil 2 that progressively preloading need to be simulated in test pit, in preloading process, because each soil layer increases gradually to the pressure of each layer of loading beam 6, do not promoted by soil layer with the position that guarantees soil pressure loading surface 7 so need increase gradually each layer of load that loads actuator 3;
2) after native 2 preloadings of test complete, on a soil layer of needs simulation, pressure transducer is set, the loading actuator 3 that this soil layer is corresponding reduces load gradually, the loading beam 6 that this soil layer is corresponding is promoted backward by this soil layer, destroy until this soil layer distortion is excessive, in this process, the power that this soil layer produces soil pressure loading surface 7 is exactly the active earth pressure of this soil layer;
3) active earth pressure while obtaining this soil layer destruction by above-mentioned pressure transducer;
4) return to step 1), repeating step 1) to 3), obtain the active earth pressure while needing another soil layer of simulation to destroy.
By above method, the active earth pressure can obtain each soil layer destruction time, is relevant research project service.
As shown in Figure 1, be the pressure distribution of each soil layer in the test soil at research dock structure 13 places, and then can obtain load and the impact of each soil layer on dock structure.