This study was performed an experimental study on mortar containing phytoncide solution. The compressive strength properties with various phytoncide containing ratios were evaluated. The phytoncide solution containing ratios adopted in this study were 0, 2, 4, 6, 8 and 10%. The compressive strength was measured at 3, 7 and 28 days for the hardened mortar specimens. According to the experimental results, the phytoncide has not affect the compressive strength and flow.

Environmental pollution is the major problem associated with rapid industrialization, urbanization and rise in living standards of people. In order to reduce environmental pollution, therefore, shielding materials using industrial waste resources were developed and the radiation shielding performance was evaluated.

Vegetation has a great importance in erosion control and slope stabilization, protecting and restraining the surface soil and increasing the strength and competence of the soil mass. However, normal green soil have poor adhesion to slopes. In order to enhance the adhesion, therefore, the vegetation effect of green slope soil mixed with cement materials was investigated in this study.

The purpose of this study is to develop a durable packaging concrete using silica - based LCD waste glass. In order to verify the performance of the waste glass mixed pavement concrete, four types of concrete mixture were classified into general concrete, fly ash concrete, LCD concrete and LCD + fly ash concrete. The performance of the durable concrete pavement was tested for compressive strength, alkali - silica reaction, freezing - thawing, saltation and abrasion resistance. The purpose of this study was to develop a high - performance pavement concrete manufacturing technology using LCD waste glass powder.

The joints in this construction are formed through the bonding shear evaluation method during the placement of ultra-high-performance concrete (UHPC). The evaluation items include push-off tests for homogeneous UHPC + UHPC. The experimental samples comprised a monolithic placement as the baseline, two levels for the separated placement according to the compression strength of concrete, and five levels for the interface treatment. The bonding shear performance for the homogeneous UHPC + UHPC construction linearly increased with the width and depth of the grooves used for the interface treatment. The increase in the number of grooves and their cross-sectional areas only slightly influenced the bonding shear performance. The optimal interface treatment method for the homogeneous UHPC + UHPC construction grooves was at least 30 mm.

This study is to investigate and analyze the correlation of carbonation according to strength of concrete members for bridge in marine enviroment. Also depth of carbonation according to age for 100 years is estimated by carbonation rate coefficient. As a result of the measurement, it was found that the depth of carbonation decreases with increasing strength. This is because it is considered that water-cement ratio and amount of unit cement are influenced by the concrete mixing. Also, It is anticipated that rebar corrosion due to carbonation will not occur in concrete members.

This study presents a technique for measuring the local strain of RC columns using high strength materials. A acrylic rod with strain gauges at intervals of 5 mm were embedded in high-strength RC columns. Under uniaxial compression loading, the local strain of the column was measured with strain gauges attached to the acrylic rod. It was confirmed from experimental results that the technique applied in this study is very effective in measuring the local strain of high-strength RC columns and the compressive failure of the high-strength RC columns is concentrated in some local regions.

This paper reports the absorption capacity of super-absorbent polymer (SAP) in water and cement pore solution. This was considered for the free water requirement for self-desiccation when the amount of internal water reduced. The physical state of particles selected from a super-absorbent polymer sample with a particle size distribution 150 μm (SAP-I) and less than 850 μm (SAP-II) monomers acrylic acid were tested at SAP 0.1g contents and time in minute 0.5, 1, 3, 5, 10, 30, and 60. The test was determined by using tea bag test method. As a result, the size of the polymers particles has a significant effect on the absorption kinetics of these polyacrylate-based polymers.

In this research work, the effect of seawater in the synthesis of fly ash based geopolymer was investigated. Fly ash as a binder was mixed with alkaline activator. The activator used was a mixture of NaOH solution and liquid sodium silicate. The NaOH solution was prepared by dissolving NaOH pellets in seawater to 10mol/L. In this study, compressive strength testing, X-ray diffraction, mercury intrusion porosimetry, scanning electron microscopy with energy dispersive spectroscopy, and analyses for acid- and water-soluble chloride contents were carried out on hardened geopolymer paste samples.

Recently, the evaluation of the grout chamber of PC bridges has been emphasized in order to prevent many problems in advance. This paper analyzes the electrical resistance of the MWCNT cement composites by electrode intervals in order to select the optimum electrode location for evaluation of grout chamber. It is concluded that the electrical resistance of the MWCNT cement composite specimens increase as the electrode interval is longer.

In this study, the absorption protection agent was applied to the surface of fiber reinforced concrete to evaluate the chloride ion penetration resistance. The evaluation was based on the method presented in KS F 2711. It was confirmed that the resistance performance against chloride ion was improved by 56∼71% when the coating material was applied.

In this paper, laboratory tensile tests were performed for the basalt, glass and carbon fiber reinforced polymer. Epoxy resin was used as the polymer for this composite material. The procedure of the experiment was based on the criteria specified in ASTM D3039 / 3039M. Moreover, a Universal Testing Machine (UTM) with 100 kN capacity was used in this experiment. Results of the performance of each composite material were analyzed. In case of fiber type, carbon fiber reinforced polymer showed the best performance; followed by basalt fiber and glass fiber reinforced polymer with the elastic modulus of 37.03 MPa and 33.10 MPa, respectively.

In this study, the characteristics of density and flow value of mortar substituted heavy weight waste glass were compared with the aggregate ratio. From the results, the density and flow value increase as the substitution of waste glass increase, however, it is considered that the increase of the aggregate ratio of 30% or more does not contribute to the increase of the density.

The purpose of this paper is to assess the effect of surface characteristic of GFRP rebar on concrete-reinforcement bond behavior. For sample preparation, 10 GFRP rebar with two types of surface conditions were used to fabricate 15×15×15cm sized GFRP reinforced concrete. Then, pull-out test was carried out on each concrete samples until the maximum bond strength was achieved. From the test result, it was found that the maximum bond strength at the lattice type is 1.38 times higher than that for unidirectional surface.

The highest latent calorific value and total calorific value of MPCM and aqueous adhesive mixed samples were 44℃, followed by 50℃, 28℃ and 31℃. At 44℃, it is considered to be the most suitable for applying it as a component of the adhesive of the decorative wood floor plate because it is higher than the MPCM combination of other melting points. The remaining samples except for 44℃ showed an increase in latent heat and total calorific value when MPCM was added to the aqueous adhesive. The higher the amount of MPCM, the higher the viscosity effect

This study introduces the result of dynamic tests carried out for the field application of ferro-nikel slag powder applied PHC PILE. For the test, a high strength, ultra high strength FNS PHC PILE was used as a test body, and a PHC PILE with a diameter of 600mm and a length of 20m was applied.

This paper presents the mechanical properties of high performance fiber-reinforced concrete composites(HFCC) according to binder replacement rate. the compressive strength and single-axial tensile strength of HFCC were evaluated according to binder replacement rete. As a result of the test, the compression strength decreased as binder replacement rates increased, and B-20 mix properties expressed the most ideal tensile strain-stress curve.

The purpose of this study is to use organisms or micro-organism functions for eco-friendly water-purification according to concentration in porous concrete using EM, utilizing bioremediation.

This paper presents the effect of recycled aggregate on the structural design in replacement of natural aggregate. As an actual structure, the concrete airshaft in a subway under construction was chosen and design-criteria obtained from experiments in association with different ratios of recycled aggregate were applied. It was found from the analysis that recycled aggregate can be applied to real concrete structures considering just strength concept and also if other unknown problems such as quality, serviceability and so on be solved.

In this study, the correlation between the durometer and the proctor penetration resistance tester, which is considered to be efficient in determining the setting time in a simple portability for soil and concrete utilizing organic lime (H) and Goto lime (G), is used. The results of the study show a high correlation between the portable hardness meter, the durometer and the proctor penetration resistance test period. Therefore, it is expected that the durometer will be useful for the measurement of setting time and the time limit.