The purpose of this current study was to evaluate direct tensile properties of engineered cemetitious composite(ECC)1) according to the volume fraction of the non-sintered binder. From the test result, the higher volume fraction of the non-sintered binder, the tensile strength was decreased but the maximum strain was increased.

In this study, We evaluated the applicability of high performance fiber reinforced cementitious composite (HPFRCC) with compressive strength of 180, 140 and 100 MPa and identical contents in steel fiber. The analysis of the flexure tensile behavior showed that HPRFCC presents deflection hardening after the initiation of cracks and exhibits higher energy absorbing capacity with high compressive strength.

Concrete subjected to dynamic loading shows local failure and it can be suppressed by improvement of flexural toughness with reinforced of fiber. Since bonding properties of fiber with matrix, specific surface area and numbers of fiber are different by fiber reinforcement type, mechanical properties of fiber reinforced concrete and improvement of impact resistance performance need to be considered. In this study, improvement mechanical properties by dynamic lodaing have been evaluated according to SF, PA fiber.

In this study, thermoplastic starch (TPS), cross-linked starch (CS), and cross-linked starch modified with glycerol (CTPS) were prepared, and the mechanical properties of the compatibilized low-density polyethylene (LDPE) blends (LDPE/TPS, LDPE/CS, and LDPE/CTPS) were investigated and compared with those of uncompatibilized LDPE/TPS, LDPE/CS, and LDPE/CTPS blends. Maleic-anhydride-grafted polyethylene was used as the compatibilizer. The enhanced tensile strength and elongation at break for the compatibilized LDPE/modified starch blends are a result of the improved compatibility between LDPE and the modified starch, which was confirmed by torque measurements and scanning electron microscopy.

In this study, the tensile properties of FRP in the oceanic environment were compared. The tensile properties at room temperature and sea water temperature were compared and the tensile properties according to the the salt stress permeation duration are compared. It is appeared that the difference in the tensile properties of composite materials due to the temperature difference very little, and it is appeared that the tensile difference due to salt stress permeation by the types of glass fiber has a difference.

본 논문에서는 RC 구조물의 보수ㆍ보강 공사에 적용되는 FRP 복합체의 역학적 특성치를 평가하기 위하여 각국에서 제안된 시험규격을 비교․분석하고, 시험편 형상 및 시험방법의 차이가 재료성능에 미치는 영향에 대한 실험적 검증을 통하여 표준화된 시험방법 및 평가기준을 도출하고자 하였다. 주 실험변수는 FRP 복합체의 종류, 시험편의 폭, 보강매수 및 가력속도로 설정하였다. 본 시험결과에 의하면, 최대 인장강도와 최소변동계수를 나타내는 인장 시험편의 폭은 FRP의 종류/직조방법에 따라 다르게 나타났으며, 특히 적층형으로 시공되는 FRP 복합체는 보강매수에 따른 인장강도의 저하현상이 관측되므로, 이를 적절히 고려할 수 있는 평가기준의 설정이 필요할 것으로 판단된다.