• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.362-367
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• 1998

The purpose of this study is to examine the influences of polystyrene content and St/UP on the setting shrinkage and strengths of polymer mortar with waste expanded polystyrene resin as a shrinkage-reducing agent, and to recommend the optimum binder formulations for product of low-shrinkage polymer mortar. In this paper, polymer mortar is prepared with waste expanded polystyrene content and St/UP, and tested for setting shrinkage, flexural and compressive strengths. From the test results, irrespective of increasing of waste expanded polystyrene resin, the strengths reduction of polymer mortar with waste expanded polystyrene(EPS) resin is not recognized. And the setting shrinkage is reduced with EPS resin content. The waste expanded polystyrene resin as a shrinkage-reducing agent can be used in the same manner as commercial polystyrene resin. In this study, we can obtain the optimum mix proportions of polymer mortar using EPS resin.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.261-266
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• 2003

This study is to investigate the heating value and noxious gases generation such as CO, NO and $SO_2$ known as dangerous gas for human from specimen made of cement and lightweight aggregate. The most quanity of CO gas is generated in EPS(Expanded Poly Styrene), core of commercial sandwich panel. Although specimens mainly composed of cement discharged the relatively less CO gas than organic core such as EPS, specimens which SBR was added discharged the very much amount of CO gas similar to EPS and especially, specimens including foaming agent, gas foaming agent or redipersible powder of VA/VeoVa showed the good properties in the generation of CO gas. From the standpoint of the generation of NO and $SO_2$ gas, both the core of commercial sandwich panel such as EPS, Glass wool and specimens made with polymer dispersion such as St/BA and SBR discharge the very much amount of NO and $SO_2$ gas in comparison of the other specimens. From this study, it was confirmed that organic materials such as core of commercial sandwich panel dischared much more noxious gas than specimens composed of cement and inorganic lightweight aggregate.

• Fire Science and Engineering
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• v.25 no.6
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• pp.64-72
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• 2011

The concrete void slab structure with the existing mushroom slab, is the structure that maximizes the advantages, while minimizing the weakness with removing useless body force of the concrete part, located on the center of the slab cross-section, which does not need to support the structural weight. In this research, a fire test is performed to analyze how the blaze behave according to the thickness of slab cover, with the practical span length of concrete void slab for the slab length 7.5 m. With this heating test, we assumed the uniform-load-model considering fixed loads and live loads, and chose the standard fire test condition. We measured the temperature changes and the deflection character according to the depth from the heat exposure side, and assessed the resisting capability according to the standard KS F 2257-1. The result comes out with the EPS model can secure about 2 hour fire-resisting-capability with 50 mm of cover depth.

• Journal of the Korea Institute of Building Construction
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• v.23 no.5
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• pp.527-536
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• 2023

This research embarked on a comprehensive examination of the engineering characteristics of lightweight concrete intended for implementation in rhamen-type modular building walls. The concrete was formulated utilizing bottom ash and coated EPS beads, in accordance with the Korea Construction Standards Center(KCS) 14 20 20 "Lightweight Aggregate Concrete". Our findings articulate that while EPS beads tend to diminish the compressive strength of the lightweight concrete, they concurrently contribute to a notable reduction in unit mass. The porous nature of the bottom ash endows the material with diminished thermal conductivity. Significantly, a mixture containing 50% EPS beads and 50% BA20 aggregates, replacing half of the coarse aggregates, was found to meet the standard specifications.

• Journal of the Korea Concrete Institute
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• v.13 no.1
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• pp.30-37
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• 2001

Generally, polymer mortar made with unsaturated polyester(UP) resin has a high curing shrinkage. This is an inadequate as repair material and construction products that have been widely used for years recently. To overcome these problems, polymer researchers and engineers have used shrinkage-reducing additives, which are usually specific thermoplastic polymers. The objective of this study is to evaluate the effects of shrinkage-reducing additive on the curing shrinkage and strengths of UP mortar. UP mortars are prepared with expanded polystyrene(EPS) ratio in styrene monomer(SM), (EPS/PS, PS=EPS+SM), and the ratio of total polystyrene resin(PS) to UP resin, (PS/UP). And it is tested for viscosity of UP resin, slump-flow, working life, flexural and compressive strengths, and curing shrinkage tests. From the test results, viscosity of resin for UP mortar increases with increasing PS content. Curing shrinkage of UP mortar is considerably smaller than that of plain UP mortar, nevertheless, reduction in the strengths is not recognized according to adding PS resin. In this study, we can obtain the optimum mix proportions of UP mortar using PS resin which made of waste expanded polystyrene.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.210-217
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• 2023

Various performances of ultra-high performance concrete (UHPC) applied with microplastics and expanded polystyrene (EPS) beads were evaluated. CompressIve and flexural strength, performance after ignition, flow-down in fresh state, and effective bond strength were evaluated. Designed weight of the cement panel with these mixtures was calculated based on the flexural strength. As a result of the experiments, it was confirmed that the EPS could reduce the density of UHPC with largest range. By maximum addition of EPS beeds, the density of UHPC decreased to 1300 kg/m³, and the compressive and flexural strengths for this mixtures were in ranges of 20-30 MPa and 15-20 MPa, respectively. On the other hand, lightest cement panel could be designed with UHPC having a density ranges about 2.0 g/cm³.

• Journal of the Korean GEO-environmental Society
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• v.4 no.1
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• pp.19-28
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• 2003

Current methods for lateral thrust calculations are based on the classical formulations of Rankine or Coulomb. However, the previous studies indicate that lateral earth pressures acting on the wall stem, which is the function of deformation parameters of the backfill, are close to the active condition only in the top half of the wall stem and in the lower half of the wall stem, the lateral earth pressures are significantly in excess of the active pressures. This paper presents the compressible inclusion function of EPS which can results in reduction of static earth pressure by accomodating the movement of retained soil. A series of model tests were conducted to evaluate the reduction of static earth pressure using EPS inclusion and determine the optimum stiffness of EPS. Also, field test was conducted to evaluate the reduction of static earth pressure using EPS inclusion. Based on field test it is found that the magnitude of static earth pressure can be reduced about 20% compared with classical active earth pressure.

• Journal of the Korea Concrete Institute
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• v.26 no.4
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• pp.421-428
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• 2014

This paper describes the experimental results of insulated concrete sandwich wall panels (CSWP) with corrugated glass fiber-reinforced polymer (GFRP) shear connectors under in-plane shear loading. Corrugated GFRP shear connectors were used to improve the thermal property of insulated CSWP and to achieve composite action between the interior and exterior concrete wall panels. Test specimens were consist of three concrete panels with two insulation layers between concrete panels and middle concrete panels was loaded in the direction of gravity. To evaluate the effects of insulation types (extruded polystyrene, XPSS and expanded polystyrene, EPS), shear connector pitch (300 and 400 mm) and width (10 and 15 mm) on in-plane shear behavior of insulted CSWP, failure mode and shear flow-average relative slip relationship of specimens were investigated. Test results indicate that the bond stress between concrete panel and insulation is considerable initially. Especially in case of insulated CSWP without shear connector, initial stiffness of CSWP with XPSS is superior to that of CSWP with EPS. The shear connector's contribution to in-plane shear performance of insulated CSWP depends on the type of insulation.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.445-448
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• 2008

The unsaturated polyester(UP) and epoxy resin have a superior material properties and a chemical resistance using sewerage pipes rehabilitation. However, UP and epoxy have not a low temperatures harding, the requirement $8{\sim}11$ hours long times harding and heating system used by reinforcement liner. This study is to evaluate the effects of low temperature harding properties methyl methacrylate(MMA) monomer using expanded polystyrene(EPS) and UP in addition of initiator and promoters. From the test result, viscosity tends to increase with increasing EPS and UP contents. However, harding time change of the MMA resins which it follows in addition of the initiator and promoter.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.929-932
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• 2008

The unsaturated polyester(UP) and epoxy resin have a superior material properties and a chemical resistance using sewerage pipes rehabilitation. However, UP and epoxy have not a low temperatures harding, the requirement $8{\sim}11$ hours long times harding and heating system used by reinforcement liner. This study is to evaluate the effects of low temperature harding properties methyl methacrylate(MMA) monomer using expanded polystyrene(EPS) in addition of initiator and promoters. From the test result, viscosity tends to increase with increasing EPS contents. However, harding time change of the MMA resins which it follows in addition of the initiator and promoter.