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1

Seismic behavior of precast concrete coupled shear walls with yielding-based and friction-based coupling beams

Fang Qiang, Sun Jian, Qiu Hongxing, Dal Lago Bruno, Chen Weihong

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e104, 2023

EN

An innovative bolt-connected precast concrete (PC) shear wall structural system has recently been proposed for middle and high-rise buildings in seismic regions. As a further research step, this paper aims to investigate the seismic behavior of PC coupled shear wall with different types of dissipative coupling beams. The quasi-static cyclic tests on two PC coupled shear wall specimens with friction-based coupling beam (FCB) and yielding-based coupling beam (YCB) were conducted. Moreover, nonlinear finite element models of the specimens were established and validated with the experimental results. The results demonstrated that the proposed dissipative coupling beams can effectively couple the wall panels in elastic field, whilst they can sustain large plastic deformation adding to the structural assembly a relevant source of energy dissipation under thresholded actions. Whilst the specimen with YCB exhibited large overstrength in plastic field, the specimen with FCB provided a more stable plateau capacity associated to enhanced deformation capacity, ductility and energy dissipation. Moreover, the FCB resulted practically undamaged and immediately reusable at the end of the test, whilst the YCB was found highly plasticized and locally torn. In addition, the detailed finite element models of the test specimens accurately predicted the experimental behavior.

2

Seismic behavior of interior polyvinyl chloride-carbon fiber-reinforced polymer-confined concrete column-ring beam joints

Yu Feng, Wang Shisi, Fang Yuan, Zhang Nannan, Wang Yan, Nuermaimaiti Maimaiti

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e49, 2023

EN

Eleven interior polyvinyl chloride (PVC)-carbon fiber-reinforced polymer (CFRP)-confined concrete (PCCC) column-ring beam joints are fabricated and experimentally investigated. The impacts of axial compression ratio, frame beam reinforcement ratio, CFRP strips spacing, ring beam width and ring beam reinforcement ratio, on seismic behaviors are analyzed. All specimens show obvious failure signs, and the frame beam reinforcement ratio exerts a degree of effect on failure positions, exhibiting different failure modes, such as shear failure in the joint zone, shear-bending failure at the junction and bending failure at the frame beam. The experimental results show that the hysteresis curves are relatively full, which have roughly experienced four stages as elastic, elastic-plastic, stable and decline stages, reflecting that the interior joints have considerable seismic behavior. The increment of ring beam reinforcement ratio or ring beam width enhances the load capacity, mitigates degradation of strength and stiffness. The peak load increases by 38.63% as the ring beam reinforcement ratio increases from 0.88 to 1.5%. When the ring beam width increases from 75 to 125 mm, the peak load increases by 37.24%. Appropriately increasing axial compression ratio can raise the load capacity, alleviate strength degradation, and enhance the initial stiffness. As the axial compression ratio increases from 0.2 to 0.4, the peak load increases by19.41%. The joints with larger frame beam reinforcement ratio show higher load capacity, while the frame beam reinforcement ratio exerts marginal impacts on strength and initial stiffness degradation. The existing classical shear models and specification design formulae are used to evaluate the shear capacity of the interior joints, and the reasons for the deviations of prediction results are expounded, which provides the theoretical basis and useful reference for the subsequent establishment of a new shear capacity formula of the joints.

3

Experimental study on seismic behaviour of fully bolted concrete shear walls

Ding Tao, Shen Kaige, Tan Ding, Zhao Yong

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 3

art. no. e142

EN

Bolted precast concrete shear wall structures have the potential to be disassembled and exhibit superior seismic performance. In this study, a new type of fully bolted concrete shear wall was proposed, and its seismic behaviour was examined through cyclic loading tests. The influence of the connecting method, axial compression ratio, and interface roughness on the seismic behaviour of this fully bolted concrete shear wall was analysed, and the design method was proposed. The results showed that at the axial compression ratio of 0.05, the proposed new type of fully bolted concrete shear wall structure behaved favourable seismic performance and the energy dissipation capacity was improved about 26%. Moreover, the proposed formulas used for the calculation of the bearing capacity of this connection provide a basis for the application of the fully bolted concrete shear walls.

4

Seismic behavior and damage assessment of mid-rise cold-formed steel-framed buildings with normal and reinforced beam-column joints

Jiang Liqiang, Zhang Xingshuo, Ye Jihong, Jiang Lizhong, Zhou Lingyu

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

675--690

EN

This paper investigated the effects of normal and reinforced beam–column joints on seismic behavior and damages of mid-rise cold-formed steel (CFS) framed buildings, where the reinforced beam–column joint is strengthened by a pair of steel blocks and a gusset plate. Shaking table tests were conducted on a 5-story CFS frame building with normal beam-column joint (CFSM-NJ) and a 5-story CFS frame building with same configurations but with reinforced beam–column joint (CFSM-RJ). Formulae fitted from four damage models were used to assess the seismic damage indexes of these test buildings, and the assessed results were validated by the damage indexes observed from tests. The results show the following: (1) the CFSM-NJ failed due to plastic hinges formed at the column bases and large separate deformation at the beam-column joints; however, the weaken-story failure mode was appeared on the CFSM-RJ; (2) the peak inter-story displacement of the building was reduced about 10–30% due to the reinforced beam-column joints; (3) the Park-Ang model is more appropriate for seismic damage assessment of column bases, but all the damage models overestimates the seismic damages of CFS beams. Finally, the authors comment on the difference between the assessed seismic damage indexes and the observed results, and the maximum damage indexes obtained from the simplified formulae are recommended as the preliminary assessed damages for mid-rise CFS buildings.

5

Seismic behavior of corroded reinforced concrete column joints under low-cyclic repeated loading

Luo Xiaoyong, Cheng Junfeng, Xiang Ping, Long Hao

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

138--157

EN

To investigate the influence of corroded steel bars on seismic performance of reinforced concrete (RC) columns, eight full-scale RC columns were designed and fabricated, which were composed of one uncorroded RC column, three RC columns with longitudinal reinforcement corrosion and four stirrup-corroded RC columns. The electrochemical test was conducted to accelerate the corrosion of steel bars in RC columns, and the low-cyclic repeated loading tests on RC columns with corrosion-damaged steel bars were carried out. The seismic behavior indicators, including the hysteretic curves, skeleton curves, displacement ductility coefficient, stiffness degradation curves and energy dissipation capacity of corroded RC columns and uncorroded columns, were compared and discussed. The experimental results show that with the increase in steel bars corrosion degree, the pinch phenomenon of the hysteretic curve gradually increases, and the energy dissipation capacity, stiffness and plastic deformation capacity of specimen reduce significantly. The ductility and energy dissipation coefficient decreased by 20% and 36%, respectively, when the stirrups corrosion ratio of specimen reaches 15.2%, and a shear failure surface was formed in the plastic hinge zone at the foot of the columns, which leads to the change of failure mode from ductile bending failure to shear failure with poor ductility under the ultimate load for corroded columns. The influence of stirrup corrosion on the failure mode of specimens is remarkable, but the effect of longitudinal reinforcement corrosion is negligible for specimens with the corrosion ratio within 14.7%. The adverse effects caused by over 15.2% stirrup corrosion should be considered in seismic design of structures in seismic zone.

6

Seismic behavior of concrete-filled double-skin steel tube/moment-resisting frames with beam-only-connected precast reinforced concrete shear walls

Hu Yi, Zhao Junhai, Zhang Dongfang, Chen Yanxiong

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

967--980

EN

Concrete-filled double-skin steel tube (CFDST) attracts attention from researchers for it exhibits high strength, good ductility and energy dissipation capacity. In this paper, CFDST frame with beam-only-connected precast reinforced concrete shear wall system is pro-posed, and all the joints used high-strength bolt connection to realize fully-prefabricated construction. Three specimens were tested to obtain the seismic performance and coopera-tive mechanism of such proposed systems, and the contribution of beam-only-connected precast reinforced concrete shear wall (BRW) was quantified by comparing the results of these specimens. The results show that: (1) the BRW cooperated well with the CFDST frames, and it significant enhanced the lateral stiffness and strength of the CFDST frame; (2) all specimens tolerated more than 4% inter-story drift ratio, indicating that the specimens have good lateral deformation capacity; (3) the specimen with two pieces of BRW (BF-BRW-B) exhibited better ductility ratio by comparing with the specimen without BRW (BF) and with only one piece of BRW (BF-BRW-A); (4) relative brittle failure was occurred on the BRW in BF-BRW-A due to the shear force, which resulted in significant strength degradation and ductility reduction of the specimen, but two BRWs in BF-BRW-B could mitigate such situations. Lastly, equations were proposed to predict the lateral resistance of the test specimens.

7

Effects of staircase on the seismic behavior of RC moment frame buildings

Noorifard A., Tabeshpour M. R.

Architecture Civil Engineering Environment

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2018

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Vol. 11, no. 4

105--122

EN

Staircase has a potential to change the seismic behavior of structures, but it is often neglected during design. In this research, effects of staircase in 5 groups including 27 models have been studied. Results show that staircase constructed with the use of RC slab, performs as a K-shaped bracing in longitudinal direction and as an inclined shear wall in transverse direction, so in both directions structural stiffness increases, period and lateral displacement of structure decrease, but staircase constructed by means of stringer beam only acts as a bracing in longitudinal direction. Stiffness caused by small span, inclined RC slabs and perimeter infill walls of staircase, based on the staircase location and the number of structural bays could change mode shape and lead to torsion. Along ladder running, staircase leads shear force and bending moment of columns adjacent to the landing to increase, while the internal forces of others to decrease. The majority of adverse effects of the staircases can be prevented by isolating the staircase from master structure. In this case, only the changes in geometry of the structure due to location and dimension of staircase and arrangement of infill walls should be studied.

8

Experimental seismic performance of steel- and composite steel-panel wall strengthened steel frames

Jiang L., Zheng H., Hu Y.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 3

520--534

EN

This paper presents an experimental study to investigate the seismic performance of steel- and composite steel-panel wall strengthened steel frames (SPWF and CPWF). A detailed experimental investigation of five 1/3-scaled specimens with one-bay and single-story was conducted. The failure modes, load-carrying capacity, hysteretic behavior, ductility, energy dissipation capacity were presented and analyzed. The effects of the length-to-height ratio, stiffeners, and the type of walls on the seismic behavior were also investigated. The experimental results show that the specimens tolerate 4% to approximately 5% story drift, the steel- and composite steel-panel wall improved the seismic performance of the steel frame. The length-to-height ratio has had large effect on load-carrying capacity, initial stiffness, ductility and response modification factor. In addition, finite element (FE) models of SPWFs and CPWFs were established to simulate their nonlinear behavior, and the results were verified by the experimental results. The failure mode obtained from the numerical simulation was in accordance with the experimental phenomenon. Furthermore, formulas were developed to estimate initial lateral stiffness and shear strength of the test specimens, and such theoretical predictions were verified by the experimental results.

9

Dynamic response of the industry masonry chimney to seismic load

Murzyn I.

Czasopismo Techniczne. Budownictwo

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2016

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Y. 113, iss. 1-B

67--72

EN

The aim of this paper was to investigate the dynamic responses of the industrial masonry chimney under seismic activity. In this study peak ground accelerations equal 0.4 g were assumed for the shock. In the paper there are the results from numerical simulation. The analyses were prepared for two material models: with elastic and inelastic behavior. In both cases the homogenization model of masonry material was used. The study was prepared in ABAQUS software (Simulia, 2013).

PL

Artykuł poświęcony jest analizie odpowiedzi dynamicznej komina przemysłowego o konstrukcji murowej obciążonego odziaływaniem sejsmicznym (trzęsieniem ziemi). W pracy zaprezentowano wyniki uzyskane drogą numeryczną. Analizę przeprowadzono w pakiecie ABAQUS (Simulia, 2013). Dla potrzeb analizy zostały wykonane dwie symulacje numeryczne: liniowo sprężysta oraz analiza uwzgledniająca uplastycznienie elementów murowych. W obydwu przypadkach wykorzystano model homogeniczny dla konstrukcji murowych. W analizie wykorzystano akcelerogramy osiągające maksymalne wartości 0,4 g.

10

Evaluation of seismic behavior of irregular tube buildings in tube systems

Ghasemi A. H.

Advances in Science and Technology. Research Journal

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2016

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Vol. 10, nr 29

46--51

EN

Setbacks in the volume of a building usually arise from the demands of urban design for illumination, proportion, etc. However, in seismic events they are the cause of abrupt changes in stiffness and mass producing a concentration of stresses in the floors near the site of sudden change. In general terms, one should ensure that the transitions are as gradual as possible in order to avoid such concentration of stresses. This study is intended to investigate seismic behavior of irregular building tube in tube systems, for this purpose seismic behavior of 40-story and 60-story reinforced concrete frame building with irregular plan was evaluated, seismic behavior of irregular buildings was assessed by overall building drifts, story drifts and shear lag behavior factors.. Higher irregularities in the overall plan structure of a building increase the phenomena of story drift and shear lag phenomena. Story drift and shear lag are higher for 60-story building than for a 40-story building.