Analysis of the Influence of Different Construction Joints on the Ductility of Cast-in-Place Frame Structure

2021 ◽  
Vol 1020 ◽  
pp. 104-113
Author(s):  
Xi Kang Yan ◽  
Bei Zhang ◽  
Guo Liang Zhao ◽  
Shun Zhang
Keyword(s):  
Pressure Ratio ◽  
Concrete Columns ◽  
Frame Structure ◽  
Axial Pressure ◽  
Treatment Methods ◽  
Displacement Ductility ◽  
Construction Joint ◽  
Construction Joints ◽  
Reversed Cyclic

This article through to the two common cast-in-situ frame structure (casting of a whole, with a construction joint) and 6 root not construction joints under axial pressure ratio through concrete columns of different processing low reversed cyclic loading experiment, study their experimental phenomena, hysteresis curves, displacement ductility, stiffness degradation, thus draw the conclusion: 1, the existence of the construction joint can lead to the decline of ductility of frame structure. 2. When the test axial pressure is relatively low, the presence or absence of construction joints and different treatment methods will obviously affect the ductility of the cast-in-place frame structure. 3. When the test axial pressure is relatively high, the presence or absence of construction joints and different treatment methods will not have a significant impact on the ductility of the cast-in-place frame structure.

Experimental Study on Mechanical Property of Steel Reinforced Concrete Short Columns of T-Shaped

2007 ◽  
Vol 340-341 ◽  
pp. 1121-1126
Author(s):  
Zhe Li ◽  
Xiao Feng Zhang ◽  
Yan Feng Zhao ◽  
De Fa Wang
Keyword(s):  
Shear Strength ◽  
Mechanical Performance ◽  
Pressure Ratio ◽  
Large Degree ◽  
Seismic Intensity ◽  
Axial Pressure ◽  
Displacement Ductility ◽  
Short Columns ◽  
Test Study ◽  
The Impact

The horizontal press performance of column is deteriorated because of special-shaped section. Moreover, because the antiseismic performance of columns is worse, it is only used in regions where seismic intensity is lower. So the main problem is to enhance the ductility. This test study on mechanical performance has been carried out through fourteen SRCTSSC and RCTSSC. The study focuses on the impact of test axial pressure ratio(nt), hooped reinforcement ratio(ρv), shear span ratio(λ) and steel ratio(ρss) to the shear strength and the antiseismic performance of SRCTSSC. It can be concluded that the shear strength of SRCTSSC is increasing with the increasing of nt and ρss , but the degree of increasing is small when nt is a certainty value, and that the shear strength of SRCTSSC is decreasing with increasing of λ; The shear resistance formula of T-shaped column is derived through tests, the calculated results are in correspondence with those of the tests. It also can be concluded that the hysteretic loops of the SRCTSSC are full and the hysteretic behaviors are improved and that the displacement ductility is increasing with increasing of ρv and ρss , but decreasing with the increasing of nt and the degree of variety in high axial pressure ratio is larger than in low axial pressure ratio. If steel bars are added, the shear strength and displacement ductility of SRCTSSC is increased in a large degree, and the capacity of energy dissipation is also enhanced. This test, for applying the special-shape column to higher intensity region, has the certain instructive significance.

Bonding Mechanism of Horizontal Construction Joints

2011 ◽  
Vol 368-373 ◽  
pp. 1264-1267
Author(s):  
Chun Ming Wei ◽  
Hui Su ◽  
Qiang Zhao ◽  
Chun Li Bi
Keyword(s):  
Compressive Force ◽  
Shear Capacity ◽  
Joint Interface ◽  
Axial Compressive Force ◽  
Failure Characteristics ◽  
Displacement Ductility ◽  
Construction Joint ◽  
Construction Joints ◽  
Concrete Placement

The quality of construction joint is significantly influenced by the precision in the concrete placement. In order to obtain the mechanical properties of horizontal construction joints surface, a comprehensive research was conducted. The research focused on the tensile capacity and seismic behavior of construction joints surface. According the tests failure characteristics, four kinds of cracking model of construction joints zone were formed. Test results indicated that bond materials could increase displacement ductility more than 10％～30％. And the clamping action provided by bond materials was so good that failure didn’t occur at the construction joint itself, but in the concrete adjacent to it. Axial compressive force is advantageous for the shear capacity of construction joint interface.

Study on Seismic Performance of a Two-Bay Two-Story RCF with Construction Joint under Low-Reversed Cyclic Loading

2013 ◽  
Vol 753-755 ◽  
pp. 719-723
Author(s):  
Xi Kang Yan ◽  
Kang Ma ◽  
Cheng Dong ◽  
Lei Wang ◽  
Pei Chen
Keyword(s):  
Energy Dissipation ◽  
Cyclic Loading ◽  
Seismic Performance ◽  
Reinforced Concrete Frame ◽  
Displacement Ductility ◽  
Reversed Cyclic Loading ◽  
Concrete Frame ◽  
Construction Joint ◽  
Hysteretic Performance ◽  
Reversed Cyclic

Based on experiment of a two-bay two-story reinforced concrete frame with construction joint under low-reversed cyclic loading, hysteretic performance, displacement ductility, bearing capacity degeneration, rigidity degeneration, energy dissipation and displacement restoring capacity are studied systematically. The studies show that the frame with construction joint has not better seismic performance than the monolithic cast frame.

Numerical Limit Analysis of Slab Bridges with Construction Joints

2018 ◽  
Author(s):  
Thomas Westergaard Jensen ◽  
Linh Cao Hoang
Keyword(s):  
Carrying Capacity ◽  
Limit Analysis ◽  
Concrete Slabs ◽  
Load Carrying Capacity ◽  
Layer Model ◽  
Yield Criteria ◽  
Reinforced Concrete Slabs ◽  
Load Carrying ◽  
Construction Joints

The conic yield criteria for reinforced concrete slabs in bending are often used when evaluating the load‐carrying capacity of slab bridges. In the last decades, the yield criteria combined with numerical limit analysis have shown to be efficient methods to determine the load carrying capacity of slabs. However, the yield criteria overestimate the torsion capacity of slabs with high reinforcement ratios and it cannot handle slabs with construction joints. In this paper, numerical limit analysis with the conic yield criteria are compared with yield criteria based on an optimized layer model. The analysis show an increasing overestimation of the load carrying capacity for increasing reinforcement degrees. Furthermore, yield criteria, which combine the conic yield criteria with an extra linear criterion due to friction, are presented for slab bridges with construction joints. The yield criteria for slabs with construction joints are used, in combination with limit analysis, to evaluate a bridge constructed of pre‐cast overturned T‐beams and in‐situ concrete. The analysis show that the load carrying capacity is overestimated, when the construction joints are not considered in the yield criteria.

scholarly journals Cyclic behavior of the R/C frames with reinforced masonry infills

2020 ◽  
Vol 156 ◽  
pp. 05014
Author(s):  
Jafril Tanjung ◽  
Maidiawati
Keyword(s):  
Lateral Displacement ◽  
Brick Masonry ◽  
Frame Structure ◽  
Cyclic Behavior ◽  
Cyclic Loads ◽  
Seismic Capacity ◽  
Masonry Infill ◽  
Masonry Infills ◽  
Experimental Works ◽  
Reversed Cyclic

This study focuses on the experimental works to define the behavior of the reinforced concrete (R/C) frame model with the strengthening of the brick masonry infill by using the embedded reinforcement bars subjected to lateral reversed cyclic loads. A previous study by applying the lateral monotonic static loads showed that the embedded reinforcement bars increased the lateral capacity of the R/C frame and also delayed the failure of the brick masonry infill and R/C frame structure as well. However, in order to define its seismic capacity, a lateral reversed cyclic loading is required. The experimental works in this study were conducted by preparing and testing the 1/4 scaled-down R/C frame specimens represented the first story of the middle multi-story commonly constructed in the earthquake-prone area such as West Sumatera, Indonesia. The R/C frame specimens were two R/C frames with brick masonry infills where one of them strengthened by the embedded reinforced bars. All specimens were tested for applying the lateral reversed cyclic loads. The applied lateral load, the lateral displacement, the progressive cracks, and the failure mode of the specimens were observed and recorded during experimental works. As it was expected, the presence of the embedded reinforced bars in the brick masonry infills increases the seismic capacity and stiffness of the R/C specimens and also delayed the failure of the specimens. The experimental results in this study imply the simple strengthening method for the brick masonry infills.

Experimental study of precast beam-to-column joints with steel connectors under cyclic loading

2020 ◽  
Vol 23 (13) ◽  
pp. 2822-2834
Author(s):  
Xian Rong ◽  
Hongwei Yang ◽  
Jianxin Zhang
Keyword(s):  
Energy Dissipation ◽  
Cyclic Loading ◽  
Load Capacity ◽  
Precast Concrete ◽  
Displacement Ductility ◽  
Reversed Cyclic Loading ◽  
Column Joint ◽  
Energy Dissipation Capacity ◽  
Reversed Cyclic ◽  
The Web

This article investigated the seismic performance of a new type of precast concrete beam-to-column joint with a steel connector for easy construction. Five interior beam-to-column joints, four precast concrete specimens, and one monolithic joint were tested under reversed cyclic loading. The main variables were the embedded H-beam length, web plate or stiffening rib usage, and concrete usage in the connection part. The load–displacement hysteresis curves were recorded during the test, and the behavior was investigated based on displacement ductility, deformability, skeleton curves, stiffness degradation, and energy dissipation capacity. The results showed that the proposed beam-to-column joint with the web plate in the steel connector exhibited satisfactory behavior in terms of ductility, load capacity, and energy dissipation capacity under reversed cyclic loading, and the performance was ductile because of the yielding of the web plate. Therefore, the proposed joint with the web plate could be used in high seismic regions. The proposed joint without the web plate exhibited similar behavior to the monolithic specimen, indicating that this joint could be used in low or moderate seismic zones. Furthermore, the utilization of the web plate was vital to the performance of this system.

scholarly journals Axial Impact Load of a Concrete-Filled Steel Tubular Member with Axial Compression Considering the Creep Effect

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3134 ◽  
Author(s):  
Tao Lan ◽  
Guangchong Qin ◽  
Jinzhao Zhuang ◽  
Youdi Wang ◽  
Qian Zheng ◽  
...  
Keyword(s):  
Impact Load ◽  
Slenderness Ratio ◽  
Concrete Strength ◽  
Pressure Ratio ◽  
Impact Resistance ◽  
Axial Pressure ◽  
Axial Impact ◽  
Creep Effect ◽  
The Impact ◽  
Peak Value

The dynamic loads acting on concrete-filled steel tubular members under axial impacts by rigid bodies were studied herein by FEM. The whole impact process was simulated and the time history of the impact load was obtained. The effects of eight factors on the axial impact load were studied; these factors were the impact speed, mass ratio, axial pressure ratio, steel ratio, slenderness ratio, concrete strength, impact position, and boundary conditions. Besides this, the effects of concrete creep on the impact load were also considered by changing the material parameters of the concrete. The results show that axial impact load changes with time as a triangle. The peak value of impact load increases and the impact resistance improves with the growth of the axial pressure ratio, steel ratio, slenderness ratio, and concrete strength after creep occurs. As the eccentricity of the axial impact acting on a concrete-filled steel tubular member increases, the peak value of the impact load decreases. The enhancement of constraints at both ends of the member can improve the impact resistance. The creep reduction coefficients for the peak axial impact load of a concrete-filled steel tubular member under axial compression and considering the creep effect over 6 months and 30 years are 0.60 and 0.55, respectively. A calculation formula for the peak value of impact load was suggested based on the existing formula, and its accuracy was proved by finite element calculation in this study.

scholarly journals Arrangement of construction joints in cast-in-place slabs

2019 ◽  
Vol 97 ◽  
pp. 04023
Author(s):  
Irina Yakovleva ◽  
Valentina Kurochkina
Keyword(s):  
Reinforced Concrete ◽  
Strength Properties ◽  
Concrete Slabs ◽  
Construction Joint ◽  
Regulatory Documents ◽  
Reinforced Concrete Slabs ◽  
Early Removal ◽  
Construction Joints ◽  
Under Construction

Within latest decades cast-in-place construction of residential houses has been actively developed. Works on erection of cast-in-place frame of the building are normally performed by phases, which results in a necessity to arrange construction joints of concreting. In accordance with regulatory documents, it is allowed to arrange construction joints in any place of the slab, in parallel with its less side. As well, it is necessary to observe the technology for joint arrangement. As practice shows, observing only technology of construction joint arrangement is insufficient to provide for strength properties of cast-in-place reinforced-concrete slabs. This article provides an analysis of actual geodetic pre-construction surveys, design and theoretically-calculated solutions; case study is a multistoried building under construction. On which basis, excessive slab deflections in the places of construction joints, were detected. It is established, that the main reason for deflection occurrence is early removal of slab formwork and installation of supports for temporary supporting. On the basis of obtained findings authors make conclusions regarding compulsory observance of the technology for construction joint arrangement, regarding a necessity to remove formwork according to common standards 70.13330.2012; as well, it is recommended to leave formwork under construction joints until concrete gains 100% of ruggedness.

Sign in / Sign up

Export Citation Format

Share Document