Research On The Distribution Of Earth Pressure On Inner-brace Retaining Structure Of Deep Excavation

As the exploitation of underground space and the high-rise structures in urban, a lager number of deep foundation excavations have appeared lately. Their scale and depth increase constantly. But the soil theory exist some serious drawbacks. The distribution of soil pressure on the retaining walls of rigidity can get through calculating by Coulomb and Rankine theory. While on the flexible retaining wall, it's more complicated and means above mentioned are out of commission.Through interior model test of the two inner supporting and underground continuous wall, simulating the deep foundation pit construction and excavation process, through inspection of each volume of the test conditions supporting structure on the model of earth pressure. The change of the earth stress distribution patterns of the two inner supporting is analyzed. Model test's results showed that active stress of supporting structure with two inner supporting is greater than Rankine active earth pressure. The stress of experimental data is closer to with the static stress at the upper part of foundation, even larger than static earth pressure, while it is between the range of active earth pressure and the static earth pressure in , at the lower part of and below the bottom of the pit. The calculation of earth stress on the supporting structure using of Terzaghi - Peck earth pressure envelope diagram supporting is safer. Using geotechnical engineering application of numerical analysis software ABAQUS, and simulating deep foundation pit with underground continuous wall and two inner supporting, taking into account the actual separation step excavation works, we can obtain the earth stress distribution behind the continuous walls. With model tests and numerical simulation of a comparative analysis between the two is closer.By the earth pressure distribution curve analyzed from the test, simulation, and measured, it can be found that the actual values of earth pressure are between Rankine active earth pressure and static pressure. Therefore, to two inner supporting structure , the following formula is suggested to use for the active earth pressure, e = Ae_o +Be_a, A ranged from0.4 to 0.5, B ranged from 0.5 to 0.6. For specific projects, A,B should be based on experimental analysis, engineering practice and other methods.