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1

Seismic performance of horizontal swivel system of asymmetric continuous girder bridge

Wang Jiawei, Gao Hongshuai, Zhang Kexin, Mo Zongyun, Wang Hongchung

Archives of Civil Engineering

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2023

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Vol. 69, nr 1

287--306

EN

The bridge horizontal swivel system generally adopts a symmetrical structure and uses a spherical hinge structure that can adjust the rotation to complete rotation construction. Because of the complexity of railway lines under bridges, some asymmetrical horizontal swivel systems have been increasingly applied in practical engineering in recent years. This system is more suitable for areas with complex railway lines, reduces the bridge span, and provides better economic benefits. However, it is also extremely unstable. In addition, instability can easily occur under dynamic loads, such as earthquake action and pulsating wind effects. Therefore, it is necessary to study their mechanical behavior. Based on the horizontal swivel system of an 11,000-ton asymmetric continuous girder bridge, the dynamic response of the horizontal swivel system to seismic action was studied using the finite element simulation analysis method. Furthermore, using the Peer database, seismic waves that meet the calculation requirements are screened for time-history analysis and compared to the response spectrum method. The mechanical properties of the structural system during and after rotation were obtained through calculations. During rotation, the seismic response of the structure is greater. To reduce the calculation time cost, an optimization algorithm based on the mode shape superposition method is proposed. The calculation result is 87% that of the time-history analysis, indicating a relatively high calculation accuracy.

2

Analysis of the seismic performances of structures reinforced by self-centering buckling-restrained braces

Jin Yongxu, Xu Man, Jia Jie

Archives of Civil Engineering

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2023

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Vol. 69, nr 3

645--663

EN

The self-centering buckling-restrained brace (SC-BRB) may achieve self-restoration for structures and, to a certain degree, diminish the substantial seismic residual deformation following rare earthquakes when compared to the usage of the conventional buckling-restrained brace (BRB). It may be possible to reduce the abrupt change in stiffness at the location of the strengthened stories and make the outrigger better at dissipating energy by improving the design of the energy-dissipation outrigger. This study compares the seismic performances of two types of energy-dissipation outriggers with BRB and SC-BRB web member designs during rare earthquakes so that the changes can be measured. The results show that using the SC-BRB web member design reduces the maximum inter-story drift ratio by an average of 7.68% and increases the average plastic-energy dissipation of the outrigger truss by 8.75%. The evaluation results show that the SC-BRB outrigger truss structure has better structural regularity and energy-dissipation performance. It has the ability to efficiently regulate the structural seismic response and lessen primary-structure damage.

3

Seismic performance of concrete columns confined by high‑strength stirrups

Hou Chongchi, Zheng Wenzhong, Liu Pengfei, Wang Qinghe, Qi ShaoBo

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e69, 2023

EN

The concrete columns confined by high-strength stirrups exhibited higher bearing capacity and better deformation ability. Based on the test results of concrete columns confined by high-strength stirrups under lateral cyclic loading, it is found that stirrup yield strength could not be used directly in calculating bearing capacity, because the high-strength stirrup could not yield at the peak point. Moreover, according to the seismic performance of a total of 49 sets of confined concrete columns from this paper and other 5 research papers, an easy-to-use model of skeleton curve is proposed by using a set of empirical equations to calculate the characteristic points of skeleton curve. Furthermore, based on the proposed model of skeleton curve, hysteretic rules are developed for the unloading and reloading stages by providing calculating formula of unloading stiffness and ignoring the effect of strength degradation. Finally, the proposed model of skeleton curve and hysteretic rules are verified and evaluated by comparing the calculated curves and experimental curves.

4

A review of the seismic performance behaviour of hybrid precast beam-to-column connections

Ghayeb Haider Hamad, Sulong N. H. Ramli, Razak Hashim Abdul, Mo Kim Hung, Ismail Zubaidah, Hashim Huzaifa, Gordan Meisam

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e35, 2023

EN

In order to withstand challenges such as earthquakes, it is important to appropriately design the beam-to-column connection of precast structures. Numerous precast connections were designed to be used worldwide to attain satisfactory seismic performance. The failures observed for many beam-column connections were primarily due to the brittle behaviour of poor connection details between the precast concrete members. This review article examines past experimental studies which used hybrid precast connections comprised of three types: (1) dry and wet connections with steel sections (Type I), (2) composite concrete (Type II), and (3) composite concrete and steel sections (Type III). The seismic performance behaviour of these connection types was evaluated and compared with that of the monolithic connections. The analysis showed that both the dry semi-rigid and rigid connections Type I can be implemented in the seismic zones. In addition, most of the wet connections Type I, Type II, and Type III can simulate the behaviour of monolithic rigid connections. Therefore, the wet connections Type I, Type II, and Type III can withstand high seismic excitations. Overall, the performance of hybrid dry connection Type I can be improved by using strengthening technique methods in the connection to maintain the continuity of the PC beam. Moreover, the use of composite materials with and without the steel sections as connector elements in the connection (Type II and Type III) can be a feasible method to simulate the seismic performance of monolithic connections.

5

Seismic behavior of a friction-type artificial plastic hinge for the precast beam–column connection

Huang Hua, Li Ming, Zhang Wei, Yuan Yujie

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e201, 2022

EN

This paper proposed a replaceable friction-type artificial plastic hinge (FAPH) to connect the prefabricated concrete members, characterized by direct load transmission and streamlined configuration. The FAPH device replaced the beam-end plastic hinge region in the precast structures, which could protect the concrete joint core area and other concrete components. The experiment of a precast beam–column connection with FAPH and a cast-in-situ beam–column connection was carried out. The experimental results showed that the FAPH connection had better hysteresis performances with higher bearing capacity, energy dissipation, and ductility than the cast-in-situ concrete connection. Moreover, the finite element model was calibrated and employed to perform parametric analyses, including the axial load ratio, the friction factor, the bolt preload, and the initial clearance. The FE analysis results showed that the FAPH connection would have a more attenuation of the friction force under the higher axial load ratio. Besides, the seismic performance of FAPH can be effectively improved with the increase of the friction factor and the bolt preload, and the FAPH connection exhibited a stable performance with various initial clearances. Based on the parametric analysis results, the formulas for the yield and peak bending moment capacity for the FAPH device were proposed.

6

Cyclic performance and shear resistance design of asymmetric diagonal stiffened beam-only-connected corrugated steel plate shear walls

Zheng Hong, Zhang Zhibin, Jiang Liqiang, Hu Yi, Wang Wei

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e183, 2022

EN

The corrugated plate steel shear walls (CSPWs) are widely used as lateral force resistant members in high-rise buildings. However, buckling failure still easily occurred on corrugated steel plates subjected to earthquake loads, which is not good for the energy dissipation of structures. In this paper, the asymmetric diagonal stiffened beam-only-connected corrugated steel plate shear wall (ASW) is proposed. A test-validated FE modeling method is used to investigate the seismic performance of ASW, and the results are compared with the results of unstiffened corrugated steel plate shear wall (USW). Then parametric studies on the height-to-thickness ratio, wavelength, wave height of the corrugated plate and width-to-thickness ratio of the stiffeners are performed to investigate their effects on the seismic performance of ASW. Finally, a simplified theoretical model is developed to calculate the shear resistance of ASW, and the results are validated by tests and FE results. The results show that: (1) compared to the USW, the yield load and ultimate load of ASW increase 11.7% and 13.2%, respectively; (2) the theoretical calculation results are basically consistent with the FE and test results, and the errors between them are within ± 15%. These results can be used for seismic enhancement of CSPWs and seismic design of ASW.

7

Performance study of precast reinforced concrete shear walls with steel columns containing friction-bearing devices

Fang Qiang, Qiu Hongxing, Sun Jian, Dal Lago Bruno, Jiang Hongbo

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

439--457

EN

A novel structural system based on precast reinforced concrete (RC) shear wall panels mutually connected vertically using T-connectors and horizontally using friction-bearing devices (FBDs) mounted on interposed steel columns was recently proposed. To investigate the seismic performance of the proposed precast RC shear wall system, three subassembly specimens simulating a single construction modulus were constructed and tested by considering different slot length and numbers of FBDs under quasi-static cyclic loading. Ductile flexural failure at drift of around 4.2% and load of around 265 kN was attained for both specimens with long-slot FBDs, while shear failure after moderate flexural ductility was attained at drift of around 3.8% and higher load of around 368.3 kN for specimens with short-slot FBDs, showing not-direct dependence of the load capacity on the number of FBDs installed. However, the higher number of FBDs allowed for higher hysteretic damping with a 27.3% increase in dissipated energy through cycles.

8

Experimental study on seismic performance of ultrahigh-strength steel frames with buckling-restrained braces

Pei Sheng, Zhang Zhe, Deng En-Feng, Wang Yan-Bo

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 4

493--506

EN

The application of high-strength steel (HSS) is a significant trend in the development of steel structures. Two main challenges for HSS structures in seismic design (i.e., low energy dissipation capacity and low lateral stiffness) need to be addressed before HSS structures can be widely constructed in practice. To solve those problems, the seismic performance of structures combined of HSS frames and concentric buckling-restrained braces (BRBs) was investigated in this study. Two half-scale experimental specimens with different stiffness ratios between BRB and HSS frame were fabricated and tested under constant vertical load and cyclic increasing horizontal load. The hysteretic response, horizontal bearing capacity, internal force distribution, energy dissipation capacity, and ductility of the dual system were analyzed. The results showed that the specimens exhibited overall ductile performance with high elastic stiffness, significant ductility, and excellent energy dissipation capacity. The characteristics of both specimens in the pseudo-static test can be divided into three typical phases, which were described as overall elastic phase, BRB hardening phase, and failing phase. The BRB hardening phase was characterized by high energy dissipation capacity, and the plastic deformation was limited to the BRB, so the ductile demand of HSS member in HSSF-BRB was reduced. Moreover, the effect of stiffness ratio between BRB and HSS frame on seismic performance was discussed in this paper.

9

Experimental and numerical investigation on non-welding CFDST joint for seismic evaluation of moment resisting frame

Guo Lei, Wang Jingfeng, Wang Wanqian, Liu Yong

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 2

128--145

EN

This paper aims to evaluate the seismic performance of concrete filled double-skin steel tubular (CFDST) frame structures. An experimental investigation on internal joints to CFDST columns was conducted to assess their seismic behavior, in which non-welding connection method was employed to avoid possible premature welding fracture. Experimental results declared that this type of joint behaved in a semi-rigid manner. Numerical models were then established to simulate the seismic performance of the joints. The moment–rotation relationship and shear behavior of panel zone were both accounted according to the component method and strut model, respectively. Subsequently, a CFDST moment resisting frame with non-welding connections (NWF) was numerically analyzed to detect its seismic response under design-based and maximum considered earthquakes. The numerical results confirmed that the NWF could lower the seismic response in terms of base shear force and joint moment compared with namely rigid frame (NRF). It also verified that the maximum story drift ratios of the NWF were higher than those of the NWF. Increment dynamic analyses (IDA) were also performed to evaluate the collapse behavior. Furthermore, a detailed discussion was conducted to analyze the influence of joint stiffness on global behavior of the NWF. The analytical results verified that this type of NWF had satisfied seismic behavior and excellent anti-collapse performance. More importantly, the NWF could conveniently adjust the stiffness of each story by varying the stiffness of the non-welding connection to decrease the story drift and to achieve a uniform story drift distribution.

10

Seismic behavior of frost-damaged squat RC shear walls under artificial climate environment: a further experimental research

Rong Xian-Liang, Zheng Shan-Suo, Zhang Yi-Xin, Dong Li-Guo, Liu Huan, Dai Kuang-Yu

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

103--124

EN

In cold environment, the damage of freezing and thawing poses a great threat to the safety of concrete structures. In this study, six frost-damaged squat reinforced concrete (RC) shear walls were subjected to low cyclic reversal loading to investigate the effects of axial compression ratio, concrete strength and freeze-thaw cycles (FTCs) on the seismic performance of squat RC shear walls. The seismic behavior of the test specimens was evaluated in terms of the frost action at the microstructure level, frost-heave crack patterns, damage processes, failure patterns, hysteretic behaviors, skeleton curves, deformations, and energy dissipation capacities. It shows that the boundary elements and distributed reinforcements had obvious restraining effects on the development of frost-heave cracks. The FTC action weakened the load-carrying capacity, energy dissipation capacity, and shear resistance capacity of the walls. When the number of FTCs is kept at 200, with the increase of the concrete strength, the gel structure (C-S-H) gradually evolved from fibrous to nets, also the width and number of frost-heave cracks started to reduce, and the distribution of frost-heave cracks evolved from the middle of the specimen to the perimeter. Moreover, the energy dissipation capacity and the ratio of the shear displacement on the whole displacement after cracking loading condition started to increase.

11

Experimental study on seismic performance of double-level yielding buckling-restrained braced concrete frames

Zhang Zhe, Zhang Sheng-Nan, Deng En-Feng, Zhou Tong-Tong, Yi Yu, He Hao, Li Na-Na

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

191--206

EN

This paper focused on the seismic performance of buckling-restrained braced concrete frame. Two different systems including the single-level yielding buckling-restrained braced concrete frame (SYBRBCF) and the double-level yielding buckling-restrained braced concrete frame (DYBRBCF) were designed for comparison. Compared with the single-level yielding buckling-restrained braces which are similar to many existing types of buckling-restrained braces, the double-level yielding buckling-restrained braces (DYBRBs) have two different energy absorption mechanisms that are expected to provide energy dissipations under the frequent earthquakes and rare earthquakes. To comparatively investigate the seismic performances of the two systems, cyclic tests were performed on one DYBRBCF specimen and another SYBRBCF specimen. The seismic response including the hysteretic curves, backbone curves, ductility coefficients, equivalent damping ratios, strengths, and stiffness degradations of the two experimental specimens was compared and analyzed. The test results indicate that the properly designed SYBRBCF and DYBRBCF can both exhibit the full hysteretic curves, meet the strong-column–weak-beam design requirement, and achieve the expected seismic performance. However, it was found that the ductility coefficient and energy dissipation capacity of the DYBRBCF were 72.2% and 23.4% higher than those of the SYBRBCF. The present study also provided useful design recommendations, which were beneficial to promote the application of DYBRBs.

12

Preliminary evaluation of seismic performance of engineering structures with perform 3D

Li Dongmei

Archives of Civil Engineering

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2019

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Vol. 65, nr 4

189--201

EN

This study analyzed the role of PERFORM 3D in the preliminary evaluation of seismic performance of engineering structures. Firstly, PERFORM 3D was briefly introduced, and its material constitutive model and basic model were analyzed. Then, taking a high-rise building project in Yulin, Shaanxi, China, as an example, PERFORM 3D was used to evaluate its seismic performance. After establishing the engineering model, five seismic waves were selected for simulation. The results showed that the maximum values of X-axis inter-story displacement angle and Y-axis displacement angle were 1/500 and 1/360 respectively, which were far less than the standard limit; the overall energy dissipation was good, the damping was small, the overall deformation was good, and the seismic performance was also good. In conclusion, PERFORM 3D has a good performance in the preliminary evaluation of seismic performance of engineering, and it is worth further promotion and application.

13

Seismic response characteristics of a base isolated cable-stayed bridge under moderate and strong ground motions

Javanmardi A., Ibrahim Z., Ghaedi K., Jameel M., Khatibi H., Suhatril M.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 2

419--432

EN

In this study, the seismic behavior of an existing steel cable-stayed bridge equipped with lead-rubber bearing subjected to moderate and strong earthquakes is investigated. The bridge is located at high seismic zone and experienced an earthquake in 1988 which caused the failure of one of its anchorage plate of the support. Herein, the bridge was modeled in three dimensions and the base isolators implemented at the abutments and deck-tower connection. The bridge seismic responses were evaluated through nonlinear dynamic time-history analysis. The comparative analysis confirmed that the base isolation system was an effective tool in reducing seismic force transmit from substructure to superstructure. Furthermore, the overall seismic performance of cable-stayed bridge significantly enhanced in longitudinal and transverse directions. However, it is observed that the axial force of the tower in substructure increased due to the isolation system induced torsional deformation to the superstructure under transverse seismic loads.

14

Pseudo-static experiment and analysis on seismic behavior of the RC columns strengthened by GHPFRCC

Li X., Wang J., Luo M.

Polish Maritime Research

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2015

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S 1

56--60

EN

Green high performance fiber reinforced cementitious composites (GHPFRCC) are a new class of sustainable cementitious composites, employing a high volume of fly ash to replace cement. In addition to increasing the sustainability of the construction environment, GHPFRCC exhibits a high tensile ductility and multiple cracking behaviors in the strainhardening state. These materials can effectively improve the structural energy dissipation capacity and structural durability. In this study, the optimum mixture ratio of GHPFRCC is presented established using an orthogonal experiment for a specific engineering application. The described GHPFRCC sustains the mechanical performance of concrete and is employed as the outer cladding to strengthen concrete columns. The finite element analysis of the material was based on the software ABAQUS and pseudo static experiments were conducted to exhibit retrofitting of GHPFRCC applied in the rehabilitation of seismic-damaged concrete columns. The computed and experimental results showed that GHPFRCC, while incorporating high volume fly ash, can retain significant multiple cracking behaviors. The energy dissipation capacity of the GHPFRCC reinforced concrete (RC) column is better than the comparable unreinforced column.