This study evluated the Freeze-thaw and scaling resistance characteristic of high early-strength low heat cement concrete. The result Freeze-thaw and scaling resistance appeared to be excellent, and using high early-strength low heat cement can be applied to concrete structures of road facilities.

Cold-mixed asphalt concrete is used to resurface locally damaged area as patching technique. However, due to the durability of Cold-mixed asphalt concrete, resurfacing needs recur for the patching conducted area. Throughout marshall stability tests, residual stability tests, and wheel tracking tests of 12 different resurfacing materials, additional quality standards were suggested in this study such as higher than 7350N in stability test, air void range from 3% to 10%, and 750/mm in dynamic stability.

Asphalt overlay on top of concrete pavement is commonly used in Korea. But water and deicing chemical can penetrate asphalt layer and stay at the boundary of asphalt and concrete layer, which cause accelerated degradation of concrete. Theoretically asphalt mixture is impermeable, but water can penetrate where improper compaction applied area or boundary area. Accordingly, optimum asphalt contents in existing mix design were modified in order to increase impermeability and test road was constructed with the modified method. The testing field site was monitored for 17 months and the performance of the test road was similar to the road used conventional mix design, although modified mix design used for the test road has 30% less air void. Thus, reduced pavement deterioration is expected on the concrete pavement rehabilitation with asphalt overlay

Asphalt concrete overlay is the most commonly used resurfacing technique for aged concrete pavement. However, the performance of the asphalt concrete overlay depends on how strongly the asphalt layer bond with concrete layer. Weakened bonding at the interface of asphalt and concrete pavement may contain water and deicer and eventually lead to pavement deterioration such as pothole, reflection crack, and concrete degradation. Accordingly, tensile bonding tests were conducted with various water proofing materials and the bonding performances were evaluated by using different pavement material. Emulsified asphalt waterproofing material showed superior quality in bonding, and acrylastic material waterproofing material showed inferior quality in bonding.

In 2004, 300km/h speed of high-speed rail was introduced in Korea. In recent years, policies and technologies are being developed with the goal of increased speed higher than 400km/h. HEMU-430X vehicles have been developed during the test, and technology-related infrastructure is under development. In addition, studies are underway for improving the speed of 500km/h or more. In more than 400km/h, track irregularity due to bearing force of track is increasing rapidly. In this study, applicability for the track structure with steel sleeper, to investigate alternatives that can reduce bearing force of track and maintenance costs.

In this study, to improve the early-age compressive strength of concrete, the powder of rapid setting additives crushed by treatment with functional grinding aid, the power-typed rapid setting cement clinker by sintering industrial waste and byproducts containing a large amount of CaO-SiO2-Al2O3 was developed. And, after adding smart BFS powder to powder of rapid setting additives, the strength tests were performed

To predict the characteristics of chloride ion penetration in the concrete and rebar corrosion prediction for chloride ion permeation, it is important to understand the chloride ion diffusion coefficient. It is possible that the reinforced concrete structures can be predicted accurately by the profile of the position of the rebar chloride ions using a chloride ion diffusion coefficient. On this study, analysis of chloride ion diffusion coefficient experimented in Korea and the effect of changes in the surface chloride ions concentration on chloride attacked durability design was analyzed

Recently, it is requests the reduction of self-load at structure and the cross section reduction due to the trend of making higher, larger of buildings. But The experiment of Lightweight concrete is mostly implemented in Laboratory and is rarely implemented in patch plant for application of construction site. therefore, this study will be useful at base, when the lightweight aggregate concrete is applied to construction site. so We had a comparative experiment of physical performance with in laboratory and Batch plant for lightweight aggregate concrete.

These researchers are studying on the hydration model suggestion of cement incorporating blast furnace slag in durability prediction of concrete using hydration model. So in this study it measured hydration heat according to replace ratio, water cement ratio using conduction calorimeter to acquire experiment data for experimental verification and verify hydration heat property when blast furnace slag is incorporated.

In this study, the underground box culvert were selected in nine construction sites and the influencing factors of underground structures on concrete degradation were verified through the field and laboratory experiments.

In this study, based on the field and laboratory experiments results of underground box culverts, a residual service life was numerically estimated via the statistical analysis and Monte Carlo simulation.

The tramway embedded track is the concrete slab track in which rail is embedded for transit and walking over the pavement. The multi-directional continuous supported embedded track system by liquid polyurethane has high performance in reducing sound and vibration, the advantage of maintenance abroad. Domestic newly-developed embedded track was installed in Osong-test site after laboratory test and yard test. In this paper, newly –developed Polycork ERS rail fastening system was tested and the embedded track system was tested in the field

After analyzing the engineering characteristics of backfill soil, we are trying to figure out whether or not satisfy the compaction criteria. For that purpose, Case of design and construction were investigated. I have also evaluted the effect of backfill materials engineering properties on structures according to degree of compaction.

The objective of this study is to evaluate shrinkage of heavy weight concrete. The main parameter was replacement level of fly-ash. Test results showed that shrinkage of heavy weight concrete was higher than ACI 209 and CEB-FIP codes without replacement of fly-ash in early ages. However, in fly ash substitution rate of 20% case, shrinkage of heavey weight concrete was lower than ACI 209 and CEB-FIP codes after 35 days.

The influence of micro-fiber on the autogeneous shrinkage of mortar were explored in this study. Mixtures with 0.4 of W/C are used in the test. Test results show that PVA fiber that added 2% in the mixture does not influence the autogenous shrinkage of mortar because the autogenous shrinkage causes an uniform volume changes of mortar.

There are great and comprehensive efforts to reduce green house gases, especially carbon dioxide, in a global community of nations. Carbon dioxide emissions of South Korea placed ninth in the world in 2007, 13 percent of that is a field of construction materials. Domestic portland cement(OPC) is made up of clinker, gypsum and 5% of admixtures. If 5% of Admixture contents of portland cement add to 10%, CO2 reduction effect can be expected. In this study, the strength properties of mortar using two types of cement were evaluated.

This study applied automotive vibration control technology to reduce interlayer noise of apartment housings. Light-weight impact sound and heavyweight impact sound were tested for performance evaluation of sound insulation. Test results showed that automotive vibration control technology was superior in light-weight impact, however, heavyweight impact sound was unplaced.

In this study, it was evaluated the early-strength of mock-up concrete by replacement of the flyash after it was ground by vibration mill and was modified chemically. Also, the early-strength of the specimens for maintaining structure was evaluated on the first, second, third day separately.

This experimental study examines the test results on the flexural behavior of strain-hardening cement composite (SHCC) with two types of Shrinkage Reducing Admixture (SRA). An influence of SRA on the flexural behaviors of SHCC mixes was observed.

A new system to ensure fire resistance of high strength concrete column in high-rise building with an permanent formwork made of insulation materials has been being studied. In this study, the fire resistance performance of the permanent formwork to the mixture of materials was estimated