• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.471-477
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• 1999

A new stress, load and displacement controlled direct shear apparatus has recently been developed at the Hyundai Institute of Construction Technology This direct shear apparatus is capable of testing of rock joint under constant normal stiffness, constant normal stress or constant normal load boundary conditions. This paper describes this direct shear apparatus and illustrates results of shear tests at constant normal stress condition, constant normal load condition and constant normal stiffness condition with dental stones which have a same joint roughness and unconfined compressive strength.

• Land and Housing Review
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• v.2 no.4
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• pp.471-477
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• 2011

This paper will describe the experimental results on the shear behaviors of reinforced concrete (RC) beam with recycled coarse aggregate (RCA). The primary objective of this research is to evaluate the influences of different RCA replacement percentage (i.e, 0%, 30%, 60%, and 100%) on the shear performance of reinforced concrete beams without shear reinforcement. Eight large-scale RC beams without shear reinforcement were manufactured and tested to shear failure. All had a rectangular cross-section with 400mm width ${\times}$ 600mm depth and 6000mm length, and were tested with a shear span-to-depth of 5.1. The results showed that the deflection and shear strength were little affected by the different RCA replacement percentage. Actual shear strength of each RCA beam was compared with the shear strength predicted using the provisions of ACI 318 code and Zsutty'e equation for shear design of RC beams. ACI 318 code predicted the shear strength of RCA reinforced concrete beams well.

• Journal of Korean Society of Steel Construction
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• v.9 no.2 s.31
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• pp.277-285
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• 1997

To investigate the shear strength and hysteretic behavior of SRC column to H steel beam joints, seven cruciform specimens were fabricated and tested. The test specimens showed stable hysteresis behavior with a little pinching. The strength decreased with increase in deflection after the speciemens reached at the maximum strength. The shear strength of panel zones increased with increased in the concrete amount of SRC column sections. The shear strength may conservatively be estimated by the sum of shear yielding strength of steel column web, plastic bending strength of steel column flange and ultimate shear strength of concrete in the panel zone.

• Steel and Composite Structures
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• v.29 no.1
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• pp.107-123
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• 2018

The conception and experimental assessment of a removable friction-based shear connector (FBSC) for precast steel-concrete composite bridges is presented. The FBSC uses pre-tensioned high-strength steel bolts that pass through countersunk holes drilled on the top flange of the steel beam. Pre-tensioning of the bolts provides the FBSC with significant frictional resistance that essentially prevents relative slip displacement of the concrete slab with respect to the steel beam under service loading. The countersunk holes are grouted to prevent sudden slip of the FBSC when friction resistance is exceeded. Moreover, the FBSC promotes accelerated bridge construction by fully exploiting prefabrication, does not raise issues relevant to precast construction tolerances, and allows rapid bridge disassembly to drastically reduce the time needed to replace any deteriorating structural component (e.g., the bridge deck). A series of 11 push-out tests highlight why the novel structural details of the FBSC result in superior shear load-slip displacement behavior compared to welded shear studs. The paper also quantifies the effects of bolt diameter and bolt preload and presents a design equation to predict the shear resistance of the FBSC.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.2
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• pp.95-104
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• 2004

The horizontally curved bridges have been used to connect bridges and roads. Until 1960s, they had been constructed with straight girders, called 'kinked girder bridges', which requires much cost and time-consuming construction of substructure. In case of using curved girders, practiced later, they would have many advantages such as reduction in the total construction cost and time, and ability to make aesthetic bridges. In designing plate girder bridges, it is necessary to determine the spacings between vertical stiffeners and the allowable shear stresses based on shear buckling capacity because it plays a key role in preventing the premature local shear buckling. Compared with the straight web, the critical shear buckling stresses of curved web panels vary with both aspect ratio and curvature coefficient. For designing curved web panels, a simplified formula and shear buckling coefficients were proposed by parametric models with F.E.M in this study.

• Geomechanics and Engineering
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• v.34 no.2
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• pp.173-186
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• 2023

In order to prevent environmental pollution, initiatives to increase the sustainability of resources are supported by society. However, the performance of recycled materials does not generally match that of natural materials. This study looks into the use of geogrid to improve various types of recycled aggregates. For this purpose, five different recycled aggregates were created by recycling wastes from the construction industry. Besides, direct shear tests (DS tests) were carried out on these recycled aggregates to determine their shear strengths. Following that, a triaxial geogrid was placed in the recycled aggregates to provide reinforcement, and the DS tests were conducted on the reinforced recycled aggregates. The results of the tests were also compared to those of tests performed on natural aggregates (NA). In conclusion, it was found that the recycled aggregates have lower shear strengths than the NA. Nonetheless, when reinforced with geogrid, the shear strength of the recycled concrete aggregates (RCA) and construction and demolition wastes (CDW) exceeded that of the NA. Furthermore, the geogrid reinforcement increased the shear strength of the recycled crushed bricks (CB), though not to the level of the NA.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.2
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• pp.128-135
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• 2013

In this study, one-way shear tests were performed to investigate the shear capacity of amorphous steel fiber-reinforced concrete slabs. Primary test parameters were the shear reinforcing method(Stirrups or amorphous steel fibers) and shear reinforcement ratio(0.25 and 0.5%). A series of four one-way slab specimens including a specimen without shear reinforcement and three specimens with shear reinforcements(stirrup, 0.25%, and 0.5% amorphous steel fibers) were tested. The test results showed that 0.25% amorphous steel fibers improved the shear capacity, but 0.5% amorphous steel fibers did not improve the shear capacity compared to the specimen with conventional shear reinforcement of 0.25%. Additional study is needed to understand the variation of shear capacity according to fiber volume fraction.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.749-758
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• 1998

The evaluation of shear stiffness of shear connection in composite bridges with CIP concrete deck is analysed. Shear stiffness of shear connection in full-depth precast concrete deck bridges is obtained from experiments. 3-dimensional finite element analyses of push-out specimen are carried out to investigate the effects of characteristics of filling material strength in shear connection on shear stiffness and local stress distribution. The load-slip relations obtained from the analyses are compared with those of experiments. The equation of initial shear stiffness of shear connection in precast concrete deck bridge is proposed. Linear analyses are performed to evaluate the effects of the shank diameter of shear connector and the strength of mortar on the characteristics of deterioration and failure load obtained by the failure criterions of each material. The failure loads are estimated and compared with test results.

• Journal of the Korea Concrete Institute
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• v.26 no.4
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• pp.533-543
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• 2014

Currently, composite construction of prestressed Precast Concrete (PC) and Cast-In-Place (CIP) concrete with different concrete strengths are frequently used in the modular construction. However, current design codes do not clearly define shear design methods for such composite beams. In this present study, simply supported prestressed PC-CIP composite beams without vertical shear reinforcement or only with horizontal shear reinforcement were tested to evaluate the effect of prestressing on the shear strength and the shear design method for such composite members. The test variables were the area ratio of PC and CIP concretes, prestressing force, shear span-to-depth ratio, and shear reinforcement ratio. The results showed that the shear strength was increased by the increase of prestressing force and prestressed PC area, and the decrease of shear span-to-depth ratio.

• Steel and Composite Structures
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• v.27 no.3
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• pp.389-399
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• 2018

A perforated shear connector group is commonly used to transfer shear in steel-concrete composite structures when the traditional shear stud connection is not strong enough. The multi-hole perforated shear connector demonstrates a more complicated behavior than the single connector. The internal force distribution in a specific multi-hole perforated shear connector group has not been thoroughly studied. This study focuses on the load-carrying capacity and shear force distribution of multi-hole perforated shear connectors in steel-concrete composite structures. ANSYS is used to develop a three-dimensional finite element model to simulate the behavior of multi-hole perforated connectors. Material and geometric nonlinearities are considered in the model to identify the failure modes, ultimate strength, and load-slip behavior of the connection. A three-layer model is introduced and a closed-form solution for the shear force distribution is developed to facilitate design calculations. The shear force distribution curve of the multi-hole shear connector is catenary, and the efficiency coefficient must be considered in different limit states.