• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.457-462
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• 1998

An experimental study was carried out for hybrid steel beams with reinforced concrete ends. The purpose is to examine the shear strength and to develop the design methodology of the RC-S connection region. Tested were four beams which included a reference beam and three beams with various parameters. The reference beam was used to make a comparison with remaining specimens. The test parameters were focused mostly on the concentrated shear reinforcements. The ratio of concentrated shear reinforcements and their types were investigated in this study.

• Structural Engineering and Mechanics
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• 제28권1호
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• pp.39-52
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• 2008

Column shear failures observed during recent earthquakes and experimental data indicate that shear deformations are typically associated with the amount of transverse reinforcement, column aspect ratio, axial load, and a few other parameters. It was shown that in some columns shear displacements can be significantly large, especially after flexural yielding. In this paper, a piecewise linear model is developed to predict an envelope of the cyclic shear response including the shear displacement and corresponding strength predictions at the first shear cracking, peak strength, onset of lateral strength degradation, and loss of axial-load-carrying capacity. Part of the proposed model is developed using the analysis results from the Modified Compression Field Theory (MCFT). The results from the proposed model, which uses simplified equations, are compared with the column test data.

• Steel and Composite Structures
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• 제24권1호
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• pp.1-13
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• 2017

In order to improve the deformation capacity of the high-strength concrete shear wall, five high-strength concrete shear wall specimens confined with high-strength rectangular spiral reinforcement (HRSR) possessing different parameters, were designed in this paper. One specimen was only adopted high-strength rectangular spiral hoops in embedded columns, the rest of the four specimens were used high-strength rectangular spiral hoops in embedded columns, and high-strength spiral horizontal distribution reinforcement were used in the wall body. Pseudo-static test were carried out on high-strength concrete shear wall specimens confined with HRSR, to study the influence of the factors of longitudinal reinforcement ratio, hoop reinforcement form and the spiral stirrups outer the wall on the failure modes, failure mechanism, ductility, hysteresis characteristics, stiffness degradation and energy dissipation capacity of the shear wall. Results showed that using HRSR as hoops and transverse reinforcements could restrain concrete, slow load carrying capacity degeneration, improve the load carrying capacity and ductility of shear walls; under the vertical force, seismic performance of the RC shear wall with high axial compression ratio can be significantly improved through plastic hinge area or the whole body of the shear wall equipped with outer HRSR.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.224-228
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• 1995

Addition of hooked steel fibers into the cementitious materials enhanced shear resistance and consequently improves structural behavior and shear strength of reinforced hooked steel fibrous concrete beam(RHSFCB) under the shear forces. Experimental observations were made on the main parameters effecting structural behavior of RHSFCB in this study. The volume fractions of fibers, shear span to depth ratios, and spacings of stirrups were taken into account as the main parameters. Some equations reported in the literatures, regarding the predictions of the shear strength of RHSFCB have been evaluated statistically based on the total number of 95 test results on RHSFCB failed in shear on shear-flexural mode.

• 한국구조물진단유지관리공학회 논문집
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• 제6권2호
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• pp.203-210
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• 2002

In these days, High-strength steel prevails throughout the construction fields for the benefit of structural and economical aspects. But high-strength steel is used by the simple calculation of flexural capacities for the purpose of reducing flexural reinforcement. So, this paper is mainly focused on the shear behavior of high-strength steel reinforced concrete beams without stirrups comparing with normal-strength steel reinforced concrete beams. Specimens were made and tested with the experimental parameters, such as steel yield strength, reinforcement ratios and minimum shear reinforcement. The main result was that not only area but also the yield strength of flexural reinforcement should be considered to predict the shear capacities of concrete beams. In addition, the experimental results were simulated by modified compression field theory analysis program, RESPONSE 2000. A good agreement was achieved between the test results and program analyses.

• 한국환경복원기술학회지
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• 제7권2호
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• pp.46-51
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• 2004

In this paper, reinforcement of soil shear strength by bamboo(substitute materials simulating a root system) are evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\Phi}$)), using simple shear tester which clearly depicts shear deformation and controls soil suction. The results show that the internal friction angle does not change under various soil suction conditions but the apparent cohesion, which reach a peak in suction of 45cm$H_2O$ near critical capillary head, is effected by soil suction. And the reinforcement of soil strength by bamboo are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by bamboo reached a peak in suction 45cm$H_2O$ too.

• Advances in nano research
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• 제11권6호
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• pp.595-606
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• 2021

This paper conducted mainly for forecasting the behavior of the shear connectors in steel-concrete composite beams based on the different factors. The main goal was to analyze the influence of variable parameters on the shear strength of C-shaped and L-shaped angle shear connectors. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data in order to select the most influential factors for the mentioned shear strength forecasting. Five inputs are considered: height, length, thickness of shear connectors together with concrete strength and respective slip of the shear connectors after testing. The ANFIS process for variable selection was also implemented in order to detect the predominant factors affecting the forecasting of the shear strength of C-shaped and L-shaped angle shear connectors. The results show that the forecasting methodology developed in this research is useful for enhancing the multiple performances characterizing in the shear strength prediction of C and L shaped angle shear connectors analyzing.

• Geomechanics and Engineering
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• 제25권3호
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• pp.245-251
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• 2021

The present study investigated the ageing effect on compressibility, permeability and shear strength behavior of kaolin and bentonite samples in the presence of NaCl and CaCl₂ solutions. The compressibility, permeability and shear strength parameters were determined on the 60, 190, and 250 days cured samples. The results have shown that, the kaolin sample becomes more compressible in the presence Ca²⁺ ions with ageing. Generally, the normalized compression index values of bentonite samples increased at the end of 60 days and 250 days curing time periods. The normalized permeability value of kaolin decreased by ageing in the presence of Na⁺ ions almost twofold. The permeability values of bentonite increased both in NaCl and CaCl₂ solutions during ageing. In the presence of Na⁺ ions kaolin had higher max. shear stress value than Ca²⁺ ions. When the max. shear stress values of 0, 60 and 190 days samples were compared, it was seen that NaCl solution had no significant effect on the shear strength of kaolin sample. However, the shear strength of kaolin increased in the CaCl₂ solution during ageing. In the presence of Ca²⁺ ions the max. shear stress value of bentonite was higher. The results of this study have shown that ageing has significant effects on the compressibility, permeability and shear strength of kaolinitic and bentonitic clayey soils.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.179-184
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• 2005

Shear strength parameters obtained from filed survey are important factors in the analysis of slope stability. In this study, sensitivity analysis was performed to evaluate the effect of input parameters on the analysis of slope stability. The input parameters selected for sensitivity analysis were slope angle, cohesion, and friction angle. Monte-Carlo Simulation method was used for calculating input parameters and the factor of safety was computed by means of limit equilibrium method. A rock slope, which has failed in the field, was used for the sensitivity analysis in the analysis of slope stability. The result of analysis shows that the factor of safety of the rock slope was a little low. From partial correlation coefficient(PPC) of input parameters determined from the sensitivity analysis, slope stability was dependant on cohesion and slope angle. The effect of friction angle was lower than that of cohesion and slope angle on slope stability.

• Structural Engineering and Mechanics
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• 제83권5호
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• pp.671-680
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• 2022

The shear capacity of beams is an essential parameter in designing beams carrying shear loads. Precise estimation of the ultimate shear capacity typically requires comprehensive calculation methods. For steel fiber reinforced concrete (SFRC) beams, traditional design methods may not accurately predict the interaction between different parameters affecting ultimate shear capacity. In this study, artificial neural network (ANN) modeling was utilized to predict the ultimate shear capacity of SFRC beams using ten input parameters. The results demonstrated that the ANN with 30 neurons had the best performance based on the values of root mean square error (RMSE) and coefficient of determination (R²) compared to other ANN models with different neurons. Analysis of the ANN model has shown that the clear shear span to depth ratio significantly affects the predicted ultimate shear capacity, followed by the reinforcement steel tensile strength and steel fiber tensile strength. Moreover, a Genetic Algorithm (GA) was used to optimize the ANN model's input parameters, resulting in the least cost for the SFRC beams. Results have shown that SFRC beams' cost increased with the clear span to depth ratio. Increasing the clear span to depth ratio has increased the depth, height, steel, and fiber ratio needed to support the SFRC beams against shear failures. This study approach is considered among the earliest in the field of SFRC.