• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.227-234
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• 2004

Sand compaction pile (SCP) method is composed of compacted sand pile inserted into the soft clay deposit by displacement method. SCP-reinforced ground is composite soil which consists of the SCP and the surrounding soft soil. When a surcharge load is applied on composite ground, time-dependent behavior occurs in the soft soil due to consolidation according to radial flow toward SCP and stress transfer also takes place between the SCP and the soft soil. This paper presents the numerical results of cylindrical composite ground that was conducted to investigate consolidation characteristics and the stress transfer mechanism of SCP-reinforced composite ground. The results show that the consolidation of soft clay has a significant effect on the stress transfer mechanism and stress concentration ratio of composite ground

• Steel and Composite Structures
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• v.6 no.3
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• pp.183-202
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• 2006

The behavior of steel-concrete composite beams is strongly influenced by the type of shear connection between the steel beam and the concrete slab. For accurate analytical predictions, the structural model must account for the interlayer slip between these two components. This paper focuses on a procedure for response sensitivity analysis using state-of-the-art finite elements for composite beams with deformable shear connection. Monotonic and cyclic loading cases are considered. Realistic cyclic uniaxial constitutive laws are adopted for the steel and concrete materials as well as for the shear connection. The finite element response sensitivity analysis is performed according to the Direct Differentiation Method (DDM); its analytical derivation and computer implementation are validated through Forward Finite Difference (FFD) analysis. Sensitivity analysis results are used to gain insight into the effect and relative importance of the various material parameters in regards to the nonlinear monotonic and cyclic response of continuous composite beams, which are commonly used in bridge construction.

• Steel and Composite Structures
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• v.30 no.2
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• pp.185-199
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• 2019

Modular construction is an emerging technology to accommodate the increasing restrictions in terms of construction period, energy efficiency and environmental impacts, since each structural module is prefabricated offsite beforehand and assembled onsite using industrialized techniques. However, some innate structural drawbacks of this innovative method are also distinct, such as connection tying inaccessibility, column instability and system robustness. This study aims to explore the theoretical and numerical stability analysis of a tenon-connected square hollow section (SHS) steel column to address the tying and stability issue in modular construction. Due to the excellent performance of composite structures in fire resistance and buckling prevention, concrete-filled steel tube (CFST) columns are also taken into account in the analysis to evaluate the feasibility of adopting composite sections in modular buildings. Characteristic equations with three variables, i.e., the length ratio, the bending stiffness ratio and the rotational stiffness ratio, are generated from the fourth-order governing differential equations. The rotational stiffness ratio is recognized as the most significant factor, with interval analysis conducted for its mechanical significance and domain. Numerical analysis using ABAQUS is conducted for validation of characteristic equations. Recommendations and instructions in predicting the buckling performance of both SHS and CFST columns are then proposed.

• Journal of Korean Society of Steel Construction
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• v.16 no.6 s.73
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• pp.807-818
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• 2004

Experimental tests and theoretical methods of the analysis of the concrete shrinkage behaviors of steel-concrete composite girders are described herein. Steel-concrete composite test specimens were fabricated in the laboratory, and long-term behaviors such as deflections, curvatures, and strains were measured for one year. Test results were compared to the analytical results obtained by using the age-adjusted effective modulus method (AEMM). In addition, composite girders have been analyzed to investigate the effects of several parameters on the concrete shrinkage behaviors. From the long-term test results, it could be used to validate AEMM for the evaluation of the shrinkage behavior of composite girders. Because the shrinkage of the reinforced concrete slab in composite girders may lead to large tensile stresses in the concrete section, the transverse cracking of the slab could occur both in the positive and negative regions. Therefore, if the cracking of concrete would be ignored,it might lead to an overestimation of the stresses of the steel section of composite girders. Based on this research, it is proposed that the effect of transverse concrete cracking on the shrinkage behavior of steel-concrete composite bridges be considered.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.31-34
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• 2006

In this study on the appliable Asphalt sheet of monolithic and inorganic matter waterproofing material using of field because of problem of complex waterproofing sheet. Before this cement polymer modified waterproof coating and appliable asphalt sheet of monolithic whether have stability by method of construction about all style waterproofing that evaluate to new method of construction development naturally big emphasis put and try to approach. Did performance test item first at, as a result, drew by suitable thing in all KS items. This is considered to have more effective spot construction work because if means that have stability by material as well as method of construction.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.247-248
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• 2018

In order to secure the variability of long-life housing, dry walls are used. The composite gypsum board panel is the most frequently used infill system for the wall, and it is an excellent construction method in terms of constructability and economic feasibility. However, there are also problems such as the destruction of Ondol pipes at the bottom floor and being unable to fix the light weight steel frame (M-bar) when a variable composite gypsum board panel is used. To solve such problems, a wall with a method of fixing only the top part without fixing the bottom floor is developed, but it is difficult to identify the durability of ceiling frame according to the tensile force of stud and the safety according to the Stiffness and impact resistance (soft body) of ceiling frame. Therefore, this study verified the effectiveness of infill system for the wall by conducting experiment on the stiffness and impact resistance of composite gypsum board panel according to the reinforcement of ceiling frame (wooden frame, double saw-toothed bracket, Cross M-bar). As a result, it was possible to secure the safety of wooden frame while the impact resistance and the Stiffness of double saw-toothed bracket and cross M-bar were not secured.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.141-142
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• 2017

New waterproofing technologies have emerged in the field of building waterproofing due to the recent diversification of the size and type of structures, the enhancement of required performance, and the diversification of new technologies (such as materials and methods)(Sheet waterproofing material, coating waterproofing material) is reduced, and composite waterproofing materials that utilize mutual benefits are widely used by compounding them (sheet+coating film, coating film+sheet). However, it is true that there is no evaluation method that can verify these composite waterproof materials, which is the most widely used at present, but the KS standard only specifies tests for individual materials However, there is a situation in which the countermeasures without a test method for composite waterproofing become sudden.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.667-676
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• 1998

The transient analysis of partially supported laminated plates with rectangular holes under uniformly distributed transverse load is studied using finite element method. The first-order shear deformation theory and the variational energy method are employed in mathematical formulation. The effects on central deflection by plate thickness ratio, material modulus ratio, ply lamination geometry and boundary conditions are investigated Numerical results are presented and comparisons of the results by the present method with those given in the literature are made.

• The magazine of the Korean Society for Advanced Composite Structures
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• v.5 no.3
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• pp.53-64
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• 2014

• Journal of Construction Engineering and Project Management
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• v.3 no.4
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• pp.12-19
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• 2013

Green Frame is an environmentally friendly column-beam system composed of composite PC members that can increase buildings' life spans while reducing resource consumption. Typically, connections of PC and RC columns occur at the boundaries of each floor, which is at the upper section of slabs, causing the boundary of each floor to generate the maximum moment. Although it is not optimal in terms of structural safety to connect members at a location where the moment is high, this approach is highly adopted due to its constructability. We propose that a superior approach that employs the concept of connecting columns at the low bending moment zone can be applied to quickly and safely install green columns, the main structural members of Green Frame. Connection of green columns at the low bending moment zone can be classified into three techniques, depending on the method of reinforcing the joints, which have different connection characteristics and construction methods. Research is needed to compare the features of each method of reinforcing the joints so that the most appropriate column connection method can be chosen for the site conditions. This study aims to confirm the structural safety of the connection component at the low bending moment zone and to compare and analyze the construction duration, unit price, quality and safety performance of each column connection method. The study results are anticipated to activate the use of composite precast concrete and to be used as development data in the future.