• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.11a
• /
• pp.141-142
• /
• 2015

This literature study is focused on the improvement of lightweight concrete in perspective of foaming agent. Lightweight concrete is the cured concrete as putting required amount of foaming agent to slurry which is a mixture of a certain amount of cement, sand, and water. It has lower density than general concrete, because foaming agent disintegrates numerous bubbles evenly and independently. Thus, it is capable of lightening the weight and great for sound absorption and insulation, In foreign countries, studies for structural lightweight concrete mainly of tunnel grouting and weight lightening of heavy structures are going along actively. Domestically, exterior panel and ALC blocks are alternatively used for flooring. Therefore, this research consider improvement of lightweight concrete in perspective of foaming agent with foundation study.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.05a
• /
• pp.105-106
• /
• 2015

As the Long-life certification system is recently introduced in the Housing Law in Korea, it is expected that an application of the lightweight wall panel will be increased in apartment construction as the main wall system. However, the performance criteria for lightweight wall is in the early phase of its action. Therefore, it is necessary to establish the performance criteria properly by investigating performance requirement in the user's perspective. The purpose of this study is to identify of the weight of the required performance items for the lightweight wall in apartment house. To analyze the priority in the performance, an interview survey is performed; after monitering the test-bed of the lightweight walls, user and experts evaluate the performance requirements. The weight of the performance requirement is developed by AHP method.

• Journal of the Korea Institute of Building Construction
• /
• v.10 no.1
• /
• pp.181-191
• /
• 2010

Lightweight panels are currently used in many ways, such as inner walls of the skyscrapers and residential buildings in Korea. Moreover there has been an increasing of interest in developing construction method and quality improvement as many buildings became higher, because there are more advantages like constructability, finishability, and economic efficiency, etc. than previous heavy weight concrete wall. It is necessary to analyze the characteristics and evaluate the performance of lightweight panels when selecting proper methods and materials to building characteristics and builder's demand. However, there doesn't exist systematic data with a classification of lightweight panels' type and performance. The purpose of this study is to classify domestic lightweight panels by both type of exterior board and construction method, and also to evaluate each performance by surveying user's opinion.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.19 no.2
• /
• pp.216-223
• /
• 2010

The general way to process the surface by means of the laser was heat treatment for strengthening the surface hardness. They have used the laser for changing the property of the surface, especially for metal. Generally, it is recent increasing tendency to use the thin plate panel for making things smaller and lightweight. However, thin plate should be strengthened or let the thin plate panel have moment of inertia by means of engraving the groove or wave on them for lightweight and strengthening. Therefore it is expected that the thin plate panel can be harder and more stable through processing the metal surface by laser beam irradiation and the hardness of thin plate possibly can be also changed how many parts of them are harden. Through this research, it can be grasped how the hardness and mechanical characteristic changes according to width and depth of groove by laser affect the max stress by the ratio of $A_H/A_T$ (hardening area/total area) and characteristic of displacement and structural characteristic for making the thin plate harder by the strengthening metal surface of thin plate by laser through the experiment and analysis of FEA can be presented.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2003.05a
• /
• pp.31-34
• /
• 2003

Sandwich panel is composed of the facing sheets which support the external load, the cellular core with the low thermal conductivity and the adhesive agent to bond them. The cellular core was produced by binding lightweight cellular aggregates with cement and two types of acrylic base St/BA emulsion were added with a view to improving the workability ion due to high absorption of light weight aggregate and to develope more strength, respectively. This investigation is to comprehend the effect of the addition of two types of St/BA on thermal conductivity, calorific value and exhaustion content of noxious gas in addition re compressive and flexural strength. Flexural strength of the specimen made with St/BA-2 ranged 20kgf/cm2 to 25kgf/cm2 and was about 50% to 100% as high as that of the non-fiber specimen. Thermal conductivity was recorded from 2.0 to 3.0 kcal/mh$^{\circ}C$ and calorific value of St/BA modified specimen was much lower than that of commercial sandwich panel core of EPS and urethane. Careful caution has to be taken because generation of noxious gas such as CO, NO and SO2 tend to increase with addition of polymer cement ratio.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2006.05a
• /
• pp.115-118
• /
• 2006

Nowadays the using of concrete is generalized, and construction material is demanded to be lightweight according to increasing the height and capacity of buildings. Therefore, it needs to develop the products having the great quality and various performance. Extruding concrete panel made of cement, silica source, and fiber, and it is a good lightweight concrete material in durability and thermostable. The silica of important ingredient is natural material with hish SiO2 contents and difficult in supply because of conservation of environment. On the other hand, the stone powder sludge discharged about 20-30% at making process of crushed fine aggregate and it is wasted. The stone powder sludge is valuable instead of silica ole because the stone powder sludge includes water of about 20-60%, SiO2 of about 64% and it has fine particles. This experiment is on the properties of extruding concrete panel using the stone powder sludge use instead of silica. From this experiment, we find that it is possible to replace the silica as stone power sludge up to 50%,

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.1
• /
• pp.146-157
• /
• 2018

Over the last 10 years, the number of disasters has been increasing in Korea. As a result, the need for temporary residences or shelters for disaster conditions is increasing. In this study, post-disaster refugees housing was developed using lightweight composite panels that are lighter than the materials that make up the existing shelter. To accomplish this, the structural performance of the lightweight composite panel was validated. Among the performance tests on the panels, the transverse load test was conducted according to the ASTM E 72 criteria. As a result of the experiment, when each specimen was subjected to a uniformly distributed load, the allowable load was determined according to the span. All the experiments were ended due to a loss of adhesive at the junction of the skin and core. Further analysis was conducted to calculate the shear stress when the junction was dropped. The mean shear stress at the adhesive surface of a specimen, 150 mm and 200 mm in thickness, was 0.0170MPa and 0.0156MPa, respectively. This suggests that similar values were obtained from panels of equal thickness. In addition, this stress provides a criterion of judgment that could be used to inspect the structural performance of the panels. The performance of the panel was evaluated based on the allowable load, but it may be possible to increase the strength of the lightweight composite panel by improving the joining method to avoid separation from the junction.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.30 no.1
• /
• pp.33-39
• /
• 2020

Lightweight geopolymers were fabricated by using fused slag from integrated gasification combined cycle as a law material and Si sludge from silicon wafer process as a bloating material for the purpose of replacing autoclaved lightweight concrete (ALC). Density and compressive strength of geopolymers were measured and compared with the properties of ALC according to the variation of mol concentration of alkaline activator, W/S ratio, addition of fibers, and addition of polystyrene and the possibility of replacing ALC panel was estimated through the comparisons. Although the geopolymer satisfying the standard of ALC panel was not made by controlling mol concentration and W/S ratio, addition of inserts such as fibers and polystyrene insert was tried to overcome the obstacle of enhancing properties. Geopolymers cannot satisfying the standard of ALC panel by adding carbon or glass fibers; however, adding fibers can be suggested as one of the methods enhancing compressive strength because the compressive strength of the specimen containing 0.3 wt.% glass fibers was increased by 3 times. The maximum addition of polystyrene insert was turned out to be 50 vol.% and the properties of geopolymers varied by the method of insertion. When using single polystyrene insert, compressive strength was 17.8 MPa and density was 0.996 g/㎤ which were similar values to the standard of ALC panel. If the difficulties of reproductivity of production and insertion method of inserts were overcome through the future research, the geopolymers containing polystyrene inserts could possibly replace ALC panel.

• Journal of The Korean Digital Architecture Interior Association
• /
• v.12 no.1
• /
• pp.81-88
• /
• 2012

According to the survey results of the Ministry of Land, Transport and Maritime Affairs in the end of December 2011, the residential buildings was reported as 67.3% of 4,529,464 buildings. Reflected in the national energy policy, the residential building is expected that greater energy savings. To have realized the Passive House Project used the Autoclaved Lightweight Concrete(ALC) material on exterior wall, we take advantage of a very large energy savings. Therefore, this study investigate the patent documents of three major companies, SUMITOMO, CLION, ASAHI KASEI, in Japan. and analyze technical flow and benchmarking patent. As a result, the Sliding method or the Rocking method of ALC panels how to install is to be superior to high-performance drift and safety by a earthquake. And the embedded anchor in panel needs to improve the shape and the strength of bearing. Thus installation technology of the ALC exterior wall investigated in japanese patent documents is expected to the fastening units and anchors.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.1
• /
• pp.9-20
• /
• 2019

The number of natural disasters in Korea, such as earthquakes, is increasing. As a result, there is growing need for temporary residences or shelters for disaster conditions. The aim of this study was to produce post-disaster refugees housing differentiated from existing shelters using lightweight composite panels. To accomplish this, the structural performance of lightweight composite panels was validated, and an in-plane shear strength test was conducted according to the ASTM E72 criteria among the performance test methods for panels. As a result of the experiment, the maximum load for each specimen under an in-plane shear load was determined. All the experiments ended with the tear of the panel's skin section. The initial stiffness of the specimens was consistent with that predicted by the calculations. On the other hand, local crushing and tearing, as well as the characteristics of the panel, resulted in a decrease in stiffness and final failure. Specimens with an opening showed a difference in stiffness and strength from the basic experiment. The maximum load and the effective area were found to be proportional. Through this process, the allowable shear stress of the specimens was calculated and the average allowable shear stress was determined. The average ultimate shear stress of the lightweight composite panels was found to be $0.047N/mm^2$, which provides a criterion of judgement that could be used to expect the allowable load of lightweight composite panels.