Shaking table test and simulation of 12-story buildings with metallic dampers located on soft soil

A controlled rocking reinforced concrete frame is a new type of vibration control structure system that uses resilient rocking columns and joints. The effects of earthquakes on this type of structure are reduced by weakening the overall stiffness, whereas the lateral displacement is controlled by the energy-dissipation dampers introduced into the structure. Two tests were performed for research: the reversed cyclic loading test and shaking table test. Two single-span single-story controlled rocking reinforced concrete frames were designed for reversed cyclic loading tests. These tests (i.e. a column-base joint stiffness test, beam-column joint stiffness test, and frame stiffness test) were performed under different conditions. The mechanical analysis model of the rocking joints was derived from the test results. With the parameters obtained from the cyclic tests, a numerical simulation method that established the analytical model of the controlled rocking reinforced concrete frame using the program ABAQUS is proposed, and the dynamic time-history analysis results of the controlled rocking reinforced concrete frame and of the conventional approach are compared to investigate the vibration control effect and seismic performance of the controlled rocking reinforced concrete frame. In addition, the inter-story drift could be effectively controlled by adding metallic dampers, and the shaking table test models of the controlled rocking reinforced concrete frame with metallic dampers were designed and constructed. The comparison of the results of the numerical analysis and the shaking table test demonstrates that the model building of the controlled rocking reinforced concrete frame structure is efficient and that the controlled rocking reinforced concrete frame exhibits an excellent seismic performance.

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Shaking Table Test and Numerical Verification for Free Ground Seismic Response of Saturated Soft Soil

Mathematical Problems in Engineering ◽

10.1155/2018/3416315 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14

Author(s):

Xuelei Cheng ◽

Chunyi Cui ◽

Zongguang Sun ◽

Jinhong Xia ◽

Guangbing Wang

Keyword(s):

Numerical Simulation ◽

Seismic Response ◽

Effective Stress ◽

Shaking Table Test ◽

Soft Soil ◽

Pressure Ratio ◽

Free Field ◽

Shaking Table ◽

Response Characteristics ◽

Fully Coupled

This paper investigates shaking table test (1g) and numerical simulation (fully coupled) of vertically propagating shear waves for saturated soft free field. A large-scale shaking table model test was performed to study seismic response characteristics of saturated soft soil free field. According to test results of seismic response features of free field system in saturated soft soil, the free field nonlinearity fully coupled numerical model of dynamical effective stress of saturated soft soil was established using OpenSEES, based on the u-p formulations of dynamic consolidation equation as well as effective stress solution method for saturated two-phase media. The numerical simulation of the free field seismic response of saturated soft soil under various test conditions was performed and the calculated results were compared with the shaking table test results. The results show the following. (1) With the increase of input ground motion intensity, the characteristic frequency of the saturated soft free ground decreases and the damping ratio increases gradually. (2) The saturated soft soil ground has short period filtering and long period amplification effect on the horizontal input seismic loads. The failure foundation takes on the isolation and shock absorption under strong ground motions. (3) The peak pore pressure ratio of the saturated soft soil ground is located in the shallow buried soil layer, and with the increase of the input ground motion intensity, the advantage of dynamic pore pressure ratio in this area is gradually weakened. (4) The numerical simulation results are consistent with the results of the shaking table test. This fully coupled effective stress numerical method can reasonably simulate the seismic response characteristics of free field in saturated soft soil, which lay the foundation for other more complex parameter extrapolation models of saturated soft soil sites. This research can provide the necessary technical experience for experimental study on non-free field.

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Design of a shaking table test box for a subway station structure in soft soil

Frontiers of Architecture and Civil Engineering in China ◽

10.1007/s11709-007-0022-2 ◽

2007 ◽

Vol 1 (2) ◽

pp. 194-197 ◽

Cited By ~ 4

Author(s):

Linde Yang ◽

Qianqian Ji ◽

Yonglai Zheng ◽

Chao Yang ◽

Dongliang Zhang

Keyword(s):

Shaking Table Test ◽

Soft Soil ◽

Shaking Table ◽

Subway Station ◽

Station Structure

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Dynamic Behavior of Ground Improved Using a Crushed Stone Foundation Wall

Sustainability ◽

10.3390/su11102767 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2767

Author(s):

Su-Won Son ◽

Pouyan Bagheri ◽

Jin-Man Kim

Keyword(s):

Dynamic Behavior ◽

Shaking Table Test ◽

Soft Soil ◽

Shaking Table ◽

Crushed Stone ◽

Natural Period ◽

Long Period ◽

Acceleration Amplification ◽

Short Period ◽

Foundation Wall

The improvement of soft clay and dredged soils to carry structures is increasingly important. In this study, the dynamic behavior of a crushed stone foundation wall in clay soil was analyzed using a 1g shaking table test. The response accelerations and spectra for three input ground motions were analyzed relative to the distance from the foundation wall, confirming that the acceleration was damped from the outside. The acceleration according to the distance from the wall was not significant under long-period motions, while different responses were obtained under short-period motions. The increased ground stiffness provided by the crushed stone wall lowered the natural period of the ground, and the acceleration amplification under short-period seismic waves was larger than that under long-period waves. Finally, equations were derived to describe the relationship between the acceleration amplification ratio and distance from the wall. The slopes of the proposed equations are larger under shorter periods, implying that the change in acceleration change with distance from the wall is more significant under shorter periods. The results of this study can be used to inform the design of soft soil improvements and the structures built atop them.

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