Pseudo-static test research on EBIMFCW with different shear-span ratio

2019 ◽  
Vol 11 (3) ◽  
pp. 427-442
Author(s):  
Sheng-cai Li ◽  
Guo Lin
Keyword(s):  
Seismic Performance ◽  
Design Method ◽  
Initial Stiffness ◽  
Test Parameter ◽  
Content Type ◽  
Static Test ◽  
Shear Span ◽  
Loading Tests ◽  
Composite Walls ◽  
Bending Failure

Purpose The purpose of this paper is to study the seismic performance of the energy-saving block and invisible multi-ribbed frame composite walls (EBIMFCW), changing the shear-span ratio as the test parameter, the low-cycle reciprocating loading tests of six 1/2 scale wall models were carried out. Design/methodology/approach The test design method and analysis are used for the seismic performance of the EBIMFCW. Findings With the increase of shear-span ratio: the walls tend to occur bending failure even more, the initial stiffness of the wall decreases, the overall ductility of the wall is improved and the walls tend to occur bending failure. Originality/value The previous studies do not involve the seismic performance of EBIMFCW under different shear-span ratios. Therefore, the paper studies the hysteresis behavior, ductility, stiffness degradation and energy dissipation performance of EBIMFCW under different shear-span ratios.

scholarly journals Cyclic Tests and Numerical Analyses on Bolt-Connected Precast Reinforced Concrete Deep Beams

2021 ◽  
Vol 11 (12) ◽  
pp. 5356
Author(s):  
Jing Li ◽  
Lizhong Jiang ◽  
Hong Zheng ◽  
Liqiang Jiang ◽  
Lingyu Zhou
Keyword(s):  
Reinforced Concrete ◽  
Failure Mode ◽  
Seismic Performance ◽  
High Strength ◽  
Length Ratio ◽  
Frame Structures ◽  
Initial Stiffness ◽  
Frame Buildings ◽  
Parametric Analyses ◽  
Bending Failure

A bolt-connected precast reinforced concrete deep beam (RDB) is proposed as a lateral resisting component that can be used in frame structures to resist seismic loads. RDB can be installed in the steel frame by connecting to the frame beam with only high-strength bolts, which is different from the commonly used cast-in-place RC walls. Two 1/3 scaled specimens with different height-to-length ratios were tested to obtain their seismic performance. The finite element method is used to model the seismic behavior of the test specimens, and parametric analyses are conducted to study the effect on the height-to-length ratio, the strength of the concrete and the height-to-thickness ratio of RDBs. The experimental and numerical results show that the RDB with a low height-to-length ratio exhibited a shear–bending failure mode, while the RDB with a high height-to-length ratio failed with a shear-dominated failure mode. By comparing the RDB with a height-to-length ratio of 2.0, the ultimate capacity, initial stiffness and ductility of the RDB with a height-to-length ratio of 0.75 increased by 277%, 429% and 141%, respectively. It was found that the seismic performance of frame structures could be effectively adjusted by changing the height-to-length ratio and length-to-thickness of the RDB. The RDB is a desirable lateral-resisting component for existing and new frame buildings.

Test and Numerical Study on the Seismic Performance of A Cable Restrainer for Girder Bridges

2019 ◽  
Author(s):  
Yitong Gu ◽  
Wancheng Yuan ◽  
Xinzhi Dang
Keyword(s):  
Seismic Performance ◽  
Numerical Study ◽  
Design Method ◽  
Lateral Displacement ◽  
Static Test ◽  
Girder Bridges ◽  
Continuous Girder Bridge ◽  
Service Conditions ◽  
Girder Bridge ◽  
Parametric Analyses

<p>In China, most of the support systems applied by short/medium span bridges are elastomeric pad bearings (EPBs). This type of support system has no reliable connections between bearings and girders as well as bearings and piers, which will cause structural damages due to large lateral displacement of bearings under earthquakes. The restrainers used currently could restrict the deformation of bridges under normal service conditions and could only restrict unidirectional displacement. Considering the disadvantages of these restrainers, a new restrainer called Connected Cable Restrainer (CCR), which can be used in short/medium span bridges supported by EPBs, is developed in this paper. The design principle, basic configuration, isolation mechanism and the design method of CCR are introduced. A pseudo static test to study the seismic performance of CCR is conducted. Seismic responses of a 3-span continuous girder bridge with CCR are simulated using OpenSees platform and parametric analyses of the two main parameters, lateral restraining displacement and restraining stiffness, are also carried out. Results show that the deformation of bridges under normal service conditions would not be restrained using CCR and the displacement responses can be mitigated effectively by using CCR through parameter optimization.</p>

scholarly journals Test and Numerical Simulation Investigation on Seismic Performance of Different Types of Expansive Polystyrene Granule Cement Latticed Concrete Walls

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3082
Author(s):  
Xinyu Cao ◽  
Xiaojun Li ◽  
Baizan Tang
Keyword(s):  
Bearing Capacity ◽  
Seismic Performance ◽  
Hole Diameter ◽  
Initial Stiffness ◽  
Core Hole ◽  
Concrete Wall ◽  
Concrete Walls ◽  
New Model ◽  
The Core ◽  
Composite Walls

An expansive polystyrene granule cement (EPSC) latticed concrete wall with diagonal bracing is formed with a traditional EPSC latticed concrete wall skeleton with added diagonal bracing. It is a new model of non-demolding wall integrating insulation and structure. For the new model, the length of one EPSC panel is 1200 mm, which is 300 mm longer than that of the traditional one. The diagonal bracing is arranged in a 45° orthogonal grid in the new model. In contrast, the traditional type has only horizontal lattice beams and vertical lattice columns. Through the pseudo-static test of two new EPSC latticed concrete wall specimens with diagonal bracing and two traditional EPSC latticed concrete wall specimens, the seismic performance of latticed concrete walls was investigated in this study. The main difference between the specimens was the lattice form and the core hole diameter. Finite element simulation was carried out on the simplified models of a latticed concrete wall with diagonal bracing. The results showed that EPSC could work with post-poured concrete to withstand earthquake action together. Additionally, the lateral performance of the EPSC latticed concrete wall with diagonal bracing was significantly improved compared with the traditional type, and the overall seismic performance was improved, especially the energy dissipation capacity, which increased by more than 180%. The bearing capacity increased by more than 12%, when the amount of concrete was basically the same. The initial stiffness was improved by more than 52%. As the diameter of the core hole increased 20 mm, the bearing capacity improved more than 12%. Simplified modeling methods could be used to analyze the seismic performance of latticed concrete walls under lateral cyclic loading. The study reveals the seismic performance characteristics of latticed composite walls with different lattice forms and core hole diameters, and it provides technical support for the engineering application of different lattice forms and core hole diameter latticed composite walls.

Seismic behaviors of precast assembled bridge columns connected with prestressed threaded steel bar: Experimental test and hysteretic model

2020 ◽  
Vol 23 (9) ◽  
pp. 1975-1988
Author(s):  
Qifang Xie ◽  
Xudong Zhao ◽  
Xiaofei Yao ◽  
Wenming Hao ◽  
Fangzheng Hu
Keyword(s):  
Seismic Performance ◽  
Service Performance ◽  
Bridge Pier ◽  
Hysteretic Model ◽  
Initial Stiffness ◽  
Good Service ◽  
Static Test ◽  
Steel Bar ◽  
Steel Bars ◽  
Socket Connection

Three 1/10-scale bridge pier specimens were tested under quasi-static test. The specimens included two precast specimens (PC1 and PC2) and one cast-in-place reference specimen. The two precast bridge pier specimens were connected with prestressing threaded steel bar and steel flange at the connection between precast pier column and the foundation, and non-socket assembly scheme and socket assembly scheme are adopted, respectively. They were tested to verify the seismic performance of prefabricated piers connected by prestressed threaded steel bars and steel flanges and study which assembly scheme is better for non-socketed and socketed piers. The results show that the prefabricated pier with the combination of the prestressed threaded steel bars and steel flange has higher cracking load and smaller residual displacement, which indicates that it has good service performance and good self-resetting ability. Compared with the non-socket assembly scheme, the socket assembly scheme is superior due to its higher ductility, higher overall initial stiffness, and higher energy dissipation capacity. Therefore, the prefabricated assembled pier with the socket connection scheme of the combination of the prestressed threaded steel bars and steel flange has good service performance and seismic performance. After that, a hysteretic model for the precast assembled columns was proposed, which has a good agreement with the test results.

scholarly journals Cyclic Behavior of a Bamboo-Steel Hybrid Moment Frame with a Novel Energy Dissipation Connection

2019 ◽  
pp. 429-436 ◽  
Author(s):  
Zirui Huang ◽  
Dongsheng Huang ◽  
Yanhua Wang ◽  
Yan Feng
Keyword(s):  
Energy Dissipation ◽  
Design Method ◽  
Hysteresis Loops ◽  
The Other ◽  
Cyclic Behavior ◽  
Initial Stiffness ◽  
Moment Frame ◽  
Damage And Failure ◽  
Loading Tests ◽  
Cyclic Loading Tests

This paper presents a novel bamboo/wood-steel hybrid frame which uses engineered bamboo products as beams and steel as columns. The beams and columns are jointed by an innovative connection which incorporates a steel hinge and two steel brackets to carry shear force and moment from the end of beam, respectively. The bracket consists of two segments, i.e. joint segment connected to beam and the other segment, which serves as energy dissipation panel (EDP), connected to the columns via a base panel. By this way, the connection can provide sufficient initial stiffness for serviceability requirements and excellent energy dissipation capacity for seismic performances. Lateral cyclic loading tests were conducted to investigate the seismic performances of the frame. It was found that hysteresis loops of the frame with energy dissipation joints show less pinching than that of frames with dowel- or bolt-type connections; by proper designing, the damage and failure of the frame can be restricted in the EDPs of connections, whereas virtually no damage was observed in the other components of the frame; the connection can provide more than 10 % damping for the frame after the yielding of EDPs. Design method is also proposed in this paper.

scholarly journals Experimental Investigation into the Seismic Performance of Prefabricated Reinforced Masonry Shear Walls with Vertical Joint Connections

2021 ◽  
Vol 11 (10) ◽  
pp. 4421
Author(s):  
Zhiming Zhang ◽  
Fenglai Wang
Keyword(s):  
Seismic Performance ◽  
Cross Sections ◽  
Shear Walls ◽  
Construction Method ◽  
Shear Capacity ◽  
Initial Stiffness ◽  
Equivalent Viscous Damping ◽  
Displacement Ductility ◽  
Reinforced Masonry ◽  
Cracking Performance

In this study, four single-story reinforced masonry shear walls (RMSWs) (two prefabricated and two cast-in-place) under reversed cyclic loading were tested to evaluate their seismic performance. The aim of the study was to evaluate the shear behavior of RMSWs with flanges at the wall ends as well as the effect of construction method. The test results showed that all specimens had a similar failure mode with diagonal cracking. However, the crack distribution was strongly influenced by the construction method. The lateral capacity of the prefabricated walls was 12% and 27% higher than that of the corresponding cast-in-place walls with respect to the rectangular and T-shaped cross sections. The prefabricated walls showed better post-cracking performance than did the cast-in-place wall. The secant stiffness of all the walls decreased rapidly to approximately 63% of the initial stiffness when the first major diagonal crack was observed. The idealized equivalent elastic-plastic system showed that the prefabricated walls had a greater displacement ductility of 3.2–4.8 than that of the cast-in-place walls with a displacement ductility value of 2.3–2.7. This proved that the vertical joints in prefabricated RMSWs enhanced the seismic performance of walls in shear capacity and ductility. In addition, the equivalent viscous damping of the specimens ranged from 0.13 to 0.26 for prefabricated and cast-in-place walls, respectively.

Practitioner-friendly design method to improve the seismic performance of RC frame buildings

2021 ◽  
pp. 875529302098801
Author(s):  
Orlando Arroyo ◽  
Abbie Liel ◽  
Sergio Gutiérrez
Keyword(s):  
Seismic Performance ◽  
Design Method ◽  
Three Dimensional ◽  
Rc Frame ◽  
Structural System ◽  
Standard Code ◽  
Frame Buildings ◽  
Rc Frame Buildings ◽  
Mathematical Justification ◽  
Story Building

Reinforced concrete (RC) frame buildings are a widely used structural system around the world. These buildings are customarily designed through standard code-based procedures, which are well-suited to the workflow of design offices. However, these procedures typically do not aim for or achieve seismic performance higher than code minimum objectives. This article proposes a practical design method that improves the seismic performance of bare RC frame buildings, using only information available from elastic structural analysis conducted in standard code-based design. Four buildings were designed using the proposed method and the prescriptive approach of design codes, and their seismic performance is evaluated using three-dimensional nonlinear (fiber) models. The findings show that the seismic performance is improved with the proposed method, with reductions in the collapse fragility, higher deformation capacity, and greater overstrength. Furthermore, an economic analysis for a six-story building shows that these improvements come with only a 2% increase in the material bill, suggesting that the proposed method is compatible with current project budgets as well as design workflow. The authors also provide mathematical justification of the method.

Innovative Use of Profiled Steel Plates for Seismic Structural Performance

2005 ◽  
Vol 8 (3) ◽  
pp. 247-257 ◽  
Author(s):  
Y. Fukumoto ◽  
T. Takaku ◽  
T. Aoki ◽  
K. A. S. Susantha
Keyword(s):  
Numerical Analysis ◽  
Seismic Performance ◽  
Structural Design ◽  
Design Method ◽  
Steel Plates ◽  
Structural Performance ◽  
Cyclic Testing ◽  
Beam Columns ◽  
Bridge Bents ◽  
Hot Rolled

This paper presents the innovative use of hot-rolled thickness-tapered mill products, longitudinally profiled (LP) plates, for the seismic performance of bridge bents of single and portal framed piers. The study involves the inelastic cyclic testing and numerical analysis of tested beam-columns and portal frames in order to evaluate the effects of tapering ratios of LP plates, penetration of yielding, and number of locally buckled panels on their structural ductility. A structural design method is proposed for the portal frames having LP panels under cyclic loadings.

scholarly journals Impact of Variations in Test Method Parameters onIn VitroActivity of Surotomycin against Clostridium difficile and Surotomycin Quality Control Limits for Broth Microdilution and Agar Dilution Susceptibility Testing

2015 ◽  
Vol 54 (3) ◽  
pp. 749-753 ◽  
Author(s):  
Maria M. Traczewski ◽  
Jennifer Deane ◽  
Daniel Sahm ◽  
Steven D. Brown ◽  
Laurent Chesnel
Keyword(s):  
Quality Control ◽  
Clostridium Difficile ◽  
Calcium Concentration ◽  
Susceptibility Testing ◽  
Test Method ◽  
Test Parameter ◽  
Content Type ◽  
Parameter Variations ◽  
Agar Dilution ◽  
Control Limits

Test parameter variations were evaluated for their effects on surotomycin MICs. Calcium concentration was the only variable that influenced MICs; therefore, 50 μg/ml (standard for lipopeptide testing) is recommended. Quality control ranges forClostridium difficile(0.12 to 1 μg/ml) andEggerthella lenta(broth, 1 to 4 μg/ml; agar, 1 to 8 μg/ml) were approved by the Clinical and Laboratory Standards Institute based on these data.

Based on the Grey Relation Analysis of Ecological Composite Wall Seismic Performance Research

2013 ◽  
Vol 368-370 ◽  
pp. 1043-1047
Author(s):  
Yin Zhang ◽  
You Han ◽  
Shuai Liang
Keyword(s):  
Seismic Performance ◽  
Evaluation System ◽  
Design Method ◽  
Structure Design ◽  
Grey System Theory ◽  
Frame Structure ◽  
Wall Structure ◽  
Width Ratio ◽  
Grey System ◽  
Composite Wall

Ecological composite wall as ecological composite wall structure of the main stress components, the seismic performance is ecological composite wall structure seismic performance evaluation system of the main content. Based on the grey system theory, the grey correlation analysis to the key parameters (the mouth of the cave, frame structure, height to width ratio) change ecological composite wall test results are analyzed, the key parameters on the ecological composite wall the influence law of seismic performance, for choosing wall structure design method to provide basis.

Sign in / Sign up

Export Citation Format

Share Document