• Transactions of Materials Processing
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• v.16 no.4 s.94
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• pp.271-275
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• 2007

These days, recycling of plastic material has become a major issue due to the landfills and environmental problem. This study investigates the fluidity of thermoplastic vulcanizate(TPV), which can be used for an automobile part such as a weather strip, in order to replace ethylene propylene rubber(EPDM). Injection molding experiments with the spiral flow test mold and panel cover mold are conducted to examine the fluidity of TPV during injection molding. It is found out that the recycled TPV's flow length is a little bit longer than the virgin TPV. However, the filling weight for a panel cover parts by a recycled TPV is almost the same as that by a virgin TPV.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1127-1132
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• 2000

The purpose of this study is to investigate the utilization of recycled fine aggregates as a material to apply to concrete curbs. This study also intends to improve the quality of recycling aggregates by adding an excellent polyester resin for the improvement of durability, anti-corrosiveness, and strength. The experimental mixing proportion was planned to acquire optimum workability and filling capability of resin mortar mixed with the recycled fine aggregate. The curbs products made for test have four type cross sections. Their flexible fracture load is 1,918~6,883kgf and their weight is 15.31~31.61kg.

• Advances in concrete construction
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• v.4 no.4
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• pp.263-281
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• 2016

Concrete continues to be the most consumed construction material in the world, only next to water. Due to rapid increase in construction activities, Construction and Demolition (C&D) waste constitutes a major portion of total solid waste production in the world. It is important to assess the amount of C&D waste being generated and analyse the practices needed to handle this waste from the point of waste utilization, management and disposal addressing the sustainability aspects. The depleting natural resources in the current scenario warrants research to examine viable alternative means, modes and methods for sustainable construction. This study reports processing Recycled Coarse Aggregates (RCA) using a rod mill, for the first time. Parameters such as amount of C&D waste for processing, nature of charge and duration of processing time have been optimized for obtaining good quality RCA. Performance of RCA based concrete and performance enhancement techniques of 50% RCA based concrete are discussed in this paper.

• Steel and Composite Structures
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• v.22 no.4
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• pp.797-820
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• 2016

This paper simulates the hysteretic behavior of steel reinforced recycled concrete (SRRC) columns under cyclic loads using OpenSees software. The effective fiber model and displacement-based beam-column element in OpenSees is applied to each SRRC columns. The Concrete01 material model for recycled aggregate concrete (RAC) and Steel02 material model is proposed to perform the numerical simulation of columns. The constitutive models of RAC, profile steel and rebars in columns were assigned to each fiber element. Based on the modelling method, the analytical models of SRRC columns are established. It shows that the calculated hysteresis loops of most SRRC columns agree well with the test curves. In addition, the parameter studies (i.e., strength grade of RAC, stirrups strength, steel strength and steel ratio) on seismic performance of SRRC columns were also investigated in detail by OpenSees. The calculation results of parameter analysis show that SRRC columns suffered from flexural failure has good seismic performance through the reasonable design. The ductility and bearing capacity of columns increases as the increasing magnitude of steel strength, steel ratio and stirrups strength. Although the bearing capacity of columns increases as the strength grade of RAC increases, the ductility and energy dissipation capacity decreases gradually. Based on the test and numerical results, the flexural failure mechanism of SRRC columns were analysed in detail. The computing theories of the normal section of bearing capacity for the eccentrically loaded columns were adopted to calculate the nominal bending strength of SRRC columns subjected to vertical axial force under lateral cyclic loads. The calculation formulas of horizontal bearing capacity for SRRC columns were proposed based on their nominal bending strength.

• Resources Recycling
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• v.18 no.3
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• pp.27-35
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• 2009

To solve resource exhaustion and waste management problems caused by mass consumption, there are many efforts to change from resource consumption system to recycling system. Specially, interests about management of construction waste have increased, but efficient recycling system of waste concrete is not established yet. In this study, high quality recycled aggregate processing circuit was developed to recycle waste concrete. From the waste concrete which is a hydrated compound with coarse aggregate, fine aggregate, and cement material, high quality recycled coarse aggregate for concrete making was produced by autogenous milling and heat pretreatment method. After then, refinement process was performed to separate fine aggregate and cement material from waste concrete fines by sink float separation and hindered-settling separation. As a result, high quality recycled aggregate was produced from waste concrete by developed processing circuit.

• Magazine of RCR
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• v.12 no.2
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• pp.26-32
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• 2017

• Magazine of RCR
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• v.8 no.3
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• pp.25-29
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• 2013

• Magazine of RCR
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• v.3 no.1
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• pp.10-19
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• 2007

• Magazine of RCR
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• v.14 no.2
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• pp.28-34
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• 2019

• Journal of the Korean Geosynthetics Society
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• v.7 no.2
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• pp.23-29
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• 2008

The purpose of this research is to assess the application of recycled-aggregate that is gained from construction wastes as the material of compaction pile method. At the same time, the development of the new technique rectifies defects of the existing compaction pile method for soft ground improvement. In this research, laboratory chamber tests were carried out analyzing the effect of the soft ground improvement by porous concrete pile using recycled aggregate. Through the results of the laboratory chamber tests, the variations of settlement, excess pore pressure, and increment of the vertical stress with time and the behavior of the composite ground were elucidated.