Experimental study of static behaviour of stud shear connectors

2013 ◽  
Vol 40 (9) ◽  
pp. 909-916 ◽  
Author(s):  
Yi Liu ◽  
Ammar Alkhatib

An experimental program involving the test of 25 push-out specimens was conducted to study the behaviour and strength of shear studs in the application of composite bridge decks and to assess the detailing requirement specified in the code practice. Testing parameters included reinforcement mesh position, presence of stud head, and stud height. An alternative type of shear studs, referred to as adjustable studs, was also studied and its capacity was compared with conventional studs. Results showed that the position of reinforcement mesh affected the specimen failure mode and ultimate load. Comparing with the cases where the mesh was placed either flush with the stud head or above the stud, the maximum ultimate load was reached and the failure was by stud shear-off when the mesh intercepted the studs. Shear studs with heads resulted in a higher ultimate load in specimens than unheaded shear studs. In the comparison between conventional and adjustable shear studs, while they shared similar failure modes, adjustable studs showed on average lower load capacity than their conventional counterparts. For all specimens studied, only specimens with reinforcement mesh satisfying the detailing requirement were able to attain the code specified strength.

2018 ◽  
Vol 162 ◽  
pp. 04016
Author(s):  
Nabeel Al-Bayati ◽  
Bassman Muhammad ◽  
Sarah Sadkhan

Experimental program were carried out to investigate the behavior of self-compacting reinforced concrete deep beams retrofitting with carbon fiber reinforced polymer (CFRP). Six simply supported deep beams were tested under symmetrically two point loads, three beams were tested up to failure without strengthening as a control beams with different shear span to effective depth ratio (a/d) while the other two beams were loaded up to 60% from the ultimate load of control beams for each a/d ratio and then retrofitted by the same configuration of CFRP to study the effect of a/d ratio on the properties of deep beams retrofitted. a/d for tested beams were (0.8, 1, 1.2). Study was focused on determining failure loads, cracking loads, failure modes, load midspan deflection. All the beams had the same compressive strength, overall dimensions and flexural and shear reinforcement. It was concluded that using this retrofitted method is very efficient and a gain in the ultimate load capacity of the deep beams was obtained also the results showed that when a/d ratio increase from 0.8 to 1.2, the ultimate load was decrease by 25% and midspan deflection was increased approximately at all load stages for control and retrofitted beams.


2019 ◽  
Vol 10 (1) ◽  
pp. 94 ◽  
Author(s):  
Shatha Alasadi ◽  
Zainah Ibrahim ◽  
Payam Shafigh ◽  
Ahad Javanmardi ◽  
Karim Nouri

This study presents an experimental investigation and finite element modelling (FEM) of the behavior of over-reinforced simply-supported beams developed under compression with a bolt-compression steel plate (BCSP) system. This study aims to avoid brittle failure in the compression zone by improving the strength, strain, and energy absorption (EA) of the over-reinforced beam. The experimental program consists of a control beam (CB) and three BCSP beams. With a fixed steel plate length of 1100 mm, the thicknesses of the steel plates vary at the top section. The adopted plate thicknesses were 6 mm, 10 mm, and 15 mm, denoted as BCSP-6, BCSP-10, and BCSP-15, respectively. The bolt arrangement was used to implement the bonding behavior between the concrete and the steel plate when casting. These plates were tested under flexural-static loading (four-point bending). The load-deflection and EA of the beams were determined experimentally. It was observed that the load capacity of the BCSP beams was improved by an increase in plate thickness. The increase in load capacity ranged from 73.7% to 149% of the load capacity of the control beam. The EA was improved up to about 247.5% in comparison with the control beam. There was also an improvement in the crack patterns and failure modes. It was concluded that the developed system has a great effect on the parameters studied. Moreover, the prediction of the concrete failure characteristics by the FE models, using the ABAQUS software package, was comparable with the values determined via the experimental procedures. Hence, the FE models were proven to accurately predict the concrete failure characteristics.


2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Lidan Mei ◽  
Nan Guo ◽  
Ling Li ◽  
Hongliang Zuo ◽  
Yan Zhao

AbstractTraditional glulam beam connection mode has a weak ability to transfer bending moment, leading to insufficient joint stiffness and mostly in the form of simply supported beams. To make full use of material strength, a novel prestressed glulam continuous beam was proposed. On this basis, this paper put forward a new method to further improve the mechanical performance of the beams by controlling prestress. According to the estimated ultimate loads of the beams, six different control range values were formulated, and 12 continuous beams were tested for flexural performance. The effects of prestressing control on the failure modes, ultimate load capacity, and load versus deformation relationships of the glulam continuous beams were analyzed. The test results indicated that the flexural performance of the beams with prestressed control was significantly improved compared to the uncontrolled beams, the ultimate load was enhanced by 13.60%–45.11%, and the average steel wire stress at failure was increased from 70% of the designed tensile strength to 94%. Combined with the finite element analysis (FEA), the reasonable control range of the prestressed control continuous beams was18%–30% of the estimated ultimate load. The research in this paper can provide references for the theoretical analysis and engineering application of similar structures.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yang Liu ◽  
Dan Zeng ◽  
Lei Cao ◽  
Naiwei Lu

In order to improve the stiffness and shear bearing capacity of steel-UHPC composite bridge, an innovative shear connector named arc-shaped reinforcement shear connector was proposed and compared with the stud and perforated bar steel plate shear connector using the static push-out test. Considering shear connector diameter, a total of ten push-out specimens for five groups were designed. The results indicated that the failure modes and failure mechanism of the arc-shaped reinforcement shear connectors were significantly different from stud shear connector and perforated bar steel plate. Obvious failure characteristics such as crack and reinforcement were not observed for the arc-shaped reinforcement specimens except for fine cracks on the top of one specimen, but these were observed for the others two types of shear connector. The relative slip value of arc-shaped reinforcement shear connector at the maximum load was the smallest and less than 1 mm in three types of shear connectors. The stiffness and shear bearing capacity of arc-shaped reinforcement were higher than those of stud and perforated bar steel plate under the same diameter. Increasing arc-shaped reinforcement diameter could improve significantly static behavior of shear connector. When the diameter of arc-shape reinforcement was increased from 8 mm to 12 mm, the ductility factor, stiffness, and shear bearing capacity of arc-shaped reinforcement shear connector were improved by 174.32%, 214.76%, and 54.2%, respectively. A calculation method of shear bearing capacity was proposed by the least square method and multiple regression analysis and agreed well with the test result.


2007 ◽  
Vol 334-335 ◽  
pp. 381-384 ◽  
Author(s):  
Jeong Hun Nam ◽  
Soon Jong Yoon ◽  
Dong Min Ok ◽  
Sun Kyu Cho

In recent years, the FRP-concrete composite bridge deck system has been introduced because of its light-weight and durability. The FRP-concrete composite bridge deck is composed of FRP module and concrete, and they are connected with shear connectors. In order to insure the composite action between FRP module and concrete, appropriate types of shear connector need to be installed. In this study, new type of FRP shear connector was suggested and the experimental investigations are conducted based on the studies of Perfobond. In the experimental study, the push-out test was conducted and the load carrying mechanism was analyzed including the friction effect of sand coating. Considering the load carrying mechanism of perforated shear connector under shear force, the empirical equation for the prediction of shear strength of perforated FRP shear connector was suggested.


2019 ◽  
Vol 24 (2) ◽  
pp. 96
Author(s):  
Rahma Nindya Ayu Hapsari ◽  
Ilham Nurhuda ◽  
Nuroji Nuroji

Composite structures of concrete slabs and steel beams require shear connectors to transfer shear force between steel beams and concrete slabs. The strength of stud shear connector specified on SNI 03-1729-2013 only considers the effect of stud diameter, however the length of a stud may influence its behavior and strength. This research observes the effects of length and diameter (𝓁/𝒹) of shear connectors on the strength. This research was conducted using the push out method explain in AS-4347- Part I. The test specimens observed in this research were concrete and steel composites, composing IWF 350x175x11x14 mm and concrete blocks of size 450x225x160 mm. The studs were made of steel reinforcements with diameter (𝒹) of 10, 16 and 22 mm, were welded on IWF with 5 mm weld thickness. The length of studs for each stud diameter were 4d, 5d, and 6d. The results indicate that the increase in stud diameter will increase the load capacity of stud. The length of studs effect its load capacity. A slim stud experiences large bending moment at the base of the shear connector. The results show that the highest value of load capacity is measured at specimens with 𝓁/𝒹 ratio of 5.


2019 ◽  
Vol 12 (2) ◽  
pp. 337-370 ◽  
Author(s):  
E. M. XAVIER ◽  
J. G. R. NETO ◽  
A. M. C. SARMANHO ◽  
L. ROQUETE ◽  
L. G. C. De PAULA

Abstract This paper presents experimental and theoretical analysis of bolts employed as shear connectors in circular concrete-filled steel tube columns (CFTs). The theoretical results, obtained from ABNT NBR 16239:2013 formulations, were compared with the experimental results. A series of push-out tests were carried out, where the diameter and length of the bolts, the number of connectors and the concrete strength were varied. From the experimental results, it was observed that the equations from ABNT NBR 16239:2013 are conservative. Therefore, it is proposed an adjustment to the formulations in order to consider the concrete confinement. It was also verified that increments in the diameter and the length of the bolt increase the load capacity of the connector. However, the variation of the quantity of bolts and the concrete strength did not interfere in the load capacity.


2018 ◽  
Vol 21 (12) ◽  
pp. 1879-1894 ◽  
Author(s):  
Xiaoqing Xu ◽  
Yuqing Liu ◽  
Yize Zuo

To attain a better understanding of the contribution of perforated steel ribs to the load-carrying capacities of steel and concrete composite slabs, six specimens with different shear connectors and areas of steel bars were tested under negative bending. Applied load, deformation, location and subsequent trajectory of cracks, strains, and failure mode of each specimen were recorded during the tests. Shear cracks were observed in two specimens, while in the other specimens only bending cracks were found. The perforated L-shaped ribs were proved to reduce the shear crack risk of composite bridge deck slabs and have a larger contribution to the loading-carrying capacities of composite slabs than plain ribs. Based on the experimental results, calculation methods were proposed to evaluate the flexural and shear strength of composite slabs. The calculated methods can quantitatively show the favorable influence of perforated steel ribs on the loading-carrying capacities of composite slabs, and the failure modes can be well predicted.


2020 ◽  
Vol 13 (3) ◽  
pp. 167-174
Author(s):  
Kareem Mohamed Alnebhan ◽  
Muhaned A. Shallal

In this study, three specimens of Warren truss girders composite with concrete deck slab were tested experimentally under a central monotonic load to study the effect of the existence of concrete inside the chords. The load capacity, deflection, slip between the concrete slab and steel tube, and failure modes were reported. Both chords were filled with concrete to the first specimen, only the lower chord was filled with concrete and the upper chord remained hollow to the second specimen and both chords were kept hollow in the third specimen. The result indicated that the existence of concrete inside the chords has a significant effect on the load capacity, failure pattern, and the slip. The steel tubes of the upper chord filled by concrete prevent surface plasticity failure of the upper chord under loading and increase the ultimate load by 6.68 %. Also, filling the lower chord with concrete prevents the surface plasticity failure in the supports zone and caused an increase in the ultimate load by 39.59 %. The slip at the end of the specimen of two chords filled with concrete is less by 71% than the end slip of specimen of hollow top chord and higher by 46.8 % than the specimen of two hollow chords.


2018 ◽  
Vol 7 (4.20) ◽  
pp. 507
Author(s):  
Nameer A. Alwash ◽  
Fatimah H. Naser Al-Mamoori

The present study includes an experimental investigation of the behavior of square reinforced concrete slabs. These slabs are with and without edge beams under uniformly distributed load with corner supports using two types of self compacting concrete (SCC), the first type of SCC incorporated limestone filler and the other was without filler, the results obtained are compared with those obtained from conventional concrete (CC).The experimental program consists of testing nine square slab samples. Three of these slab samples are flat in shape with panel dimensions of 1050×1050×50 mm depth. The others three slab samples are of the same outer dimensions with surrounding edge beams of depth to slab thickness equal 100/50 and 100 mm width. The last three slab samples are similar to the former slab-beam systems but with increasing the depth of edge beams by 50%.In general, for a specified flat plate panel, the ultimate load carrying capacity can be increased, if the panel is restricted by four surrounding beams. The slab-beam samples with surrounding beams of depth to slab thickness equal to 3 showed greater ultimate load capacity by about 79.37%, 52% and 97.82% when compared with the corresponding flat slabs samples produced using CC, SCC with and without filler, respectively.  


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