Papers by Author: Jin Hui Liu

Abstract: The big earthquake is a sudden, devastating natural disasters, and cause great harm to social.Earthquake damage to the structure of the building is the main reason to cause personal injury.Therefore, seismic research is particularly important.With further research,seismic studies from traditional seismic structure gradually developed into the base isolation,and the basis of isolation to become a major research focus.Although many studies of base isolation structure,But for foundation isolation in limit structure research is not enough, and not paid enough attention to practical engineering.Therefore, based on the theory of structural dynamics, create a calculation model, preparation of the limit protective isolation structure analysis procedures, and validation analysis Limit Protection Isolation structure can better analyze dynamic schedule.

Abstract: Reinforcement corrosion is one of the main causes for the deterioration of reinforcement concrete structure. And it seriously affected mechanical properties of anchor structure system of underground engineering under complicated erosion environment. Based on elastic theory and assumption of maximum tensile-stress failure criterion, together with construction process of anchor structure and rust expansion critical process, reinforcement rust expansion mechanical model of anchor structure system was simplified. Elastic criterion of different initial cracking mode was rewarded under different stress ratios. According to analysis of critical cracking mode of different medium, cracking order of mortar and surrounding rock depended on their material parameters, in-situ stress and thickness of mortar cover. Critical cracking conditions of different medium without effect of in-situ stress was rewarded. The result provides a useful reference for analysis of mechanical deterioration mechanism of anchor structure and design of support structure of underground engineering.

Abstract: Because of long-term chloride erosion and alternate drying-wetting effect, anchorage support structure of underground engineering is liable to reinforced corrosion and its strength is decreased. According to previous research theory and test results, reinforced corrosion to deteriorate load-bearing role of anchorage support structure system is studied by means of numerical analysis FLAC3D and idea of finite element strength reduction. The results are as follows: (1) losses in the anchor structural performance in underground engineering with corroded reinforcements are caused by three factors: losses in the effective cross-sectional area of anchoring body, losses in the mechanical performance of reinforcing bars and losses in the bond performance of anchoring body. (2) Based on reinforcement mechanical model in FLAC3D, deterioration of mechanical performance of anchor structures caused in underground engineering was analyzed due to reinforcement corrosion. And according to idea of finite element strength reduction and results of laboratory test, deterioration analysis parameter caused by corrosion can be reduced accordingly. The research results can provide the theory support to analyze corrosion deterioration of anchor structure in underground engineering using numerical simulation.

Abstract: There have potential main-landslide and a undisturbed thin layer of siliceous rock under the left of Karst slope (K133+180), so it is easy to occur creeping slip surface because of gravity while excavating. Proceeding with geomechanics model and according to influence of heavy rainfall, two schemes proposed are analyzed by means of numerical simulation. Both the reinforcement with lattice beam and anchor cable and the reinforcement with anti-slide pile and cable satisfy stability of slope. But the second scheme has higher safety storage coefficient. And the result that the second scheme not only strength anti-shear ability but also change magnitude and trend of shear damage of potential landslide in slope is rewarded. So the restrain effect of the second scheme is better that of the first. According to engineering cost of two schemes, the cost of the reinforcement with anti-slide pile and cable is less than that of the reinforcement with lattice beam and anchor cable. So Karst slope (K133+180) is reinforced with the second scheme and it is stability undergoing strong rainfall. Experience of Karst slope (K133+180) can give useful guidance for similar projects in Karst terrain.

Abstract: Based on the tri-axial tests, the stress-strain relationship and strength properties of reinforced expensive soils are studied to get the relation between the strength index of reinforced soil and that of the corresponding plain soil. According to stress-strain relationship of reinforcement soils under different layers and principle of equivalent confining pressure, strength properties of reinforced expensive soils with failure material were analyzed. Mohr circles of different reinforcement layers were tangent to the same line while reinforcement materials fractured. With the increment of axial pressure, different layers were fractured slowly and Mohr circles extended outward. It showed that the strength of reinforcement soils increased with increasing the layers. And the tri-axial tests showed that strength envelopes of reinforcement soils with layers of flexible materials were approximately parallel. The increment of strength was only affected by increment of cohesion.

Abstract: Based on isolation theory, time-history analysis on isolation system with limiting displacement protective devices was studied by Fortran program. Isolation effect of non-isolated structure, isolated structure and limit isolated structure were analyzed. Adhesion phenomenon of algorithm is solved by subdividing time steps during program analysis. And it gets good effect. According to comparing with isolation effect of different isolated structure, the result that isolation effect of isolated structure and limit isolated structure is obvious is reward; and limit isolated structure can isolation and prevent large displacement of isolation layers to avoid structure failure under rare earthquake condition. So limit isolated structure plays a double protection for structure.