Critical Study of Corrosion Damaged Concrete Structures

Corrosion of steel reinforcement in concrete is one of the major problems with respect to the durability of reinforced concrete structures. The degradation of the structure strength due to reinforcement corrosion decreases its design life. This paper presents the literature study on the influence of the corrosion on concrete structure starting from the mechanism of the corrosion until the deterioration stage and the structural effects of corrosion on concrete structures

Critical study of corrosion damaged concrete structures

Corrosion of steel reinforcement in concrete is one of the major problems with respect to the durability of reinforced concrete structures. The degradation of the structure strength due to reinforcement corrosion decreases its design life. This paper presents the literature study on the influence of the corrosion on concrete structure starting from the mechanism of the corrosion until the deterioration stage and the structural effects of corrosion on concrete structures

Concrete Repair Using Fiber from Surgical Mask

In this new Norma, surgical mask was a thing that important to wear in public. Because of the frequent use of surgical mask, the huge of waste of surgical mask were disposed per day. The surgical mask was made from a polypropylene fiber that widely used in construction in the term of concrete fiber. Polypropylene fiber had their own credibility to provide the ductile strength for concrete to reduce the cracking of concrete that was a brittle material. To study the effectiveness of the fiber from surgical mask, this fiber was used as concrete repaired materials The material of concrete repair was the important things to provide or improved the deteriorated concrete. Therefore, this study will determine that fiber from surgical mask can be used as a concrete repaired material through the comparison of flexural strength between the controlled concrete and repaired concrete. Three methods of concrete repaired was tested in this study, single layer polypropylene fiber, single layer surgical mask fiber, and double layer surgical mask fiber. Those method was applied to deteriorated concrete prism. The result for flexural strength of concrete after repaired for all method was decreasing from the strength before repaired but the result of second method was higher than the first method and the third method was higher than the second method. The concrete failure condition, showed the failure happened on the same location failure before repaired that meant the failure happened on the concrete repaired material. However, the used of surgical mask fiber was changed failure condition of the concrete prism from sudden failure to periodic failures. Therefore, the surgical mask was effective to repair the damage concrete due to crack failure because the fiber of the surgical mask can controlled that crack

Mechanical and durability performance of lightweight concrete brick with palm oil fuel ash (POFA)

Lightweight building materials such as precast roof and wall panel has been widely used in the construction industries. This is because lightweight materials could benefits the economy and society in terms of manufacturing, transportation and handling cost. One of the most preferable lightweight material is Expanded Polystyrene (EPS). EPS consist of 98% of air and 2% of polystyrene. Therefore, EPS is very low in density which could contribute in the reduction of building materials mass. Abundance of studies has shown that EPS has significantly contribute to the reduction of brick density. EPS has been used as the aggregates replacement in concrete. However, the existing of EPS in the concrete has reduce the strength performance of the concrete. Due to this, researchers have extend their research in improvising the EPS concrete and brick strength with the addition of pozzolanic materials such as fly ash, rice husk ask, silica fume and etc [1-4]. The ability of these pozzolanic materials in enhancing the strength of brick or concrete has been proven..

A Comparative Study of Turbulence Models on Aerodynamics Characteristics of a NACA0012 Airfoil

This paper presented a computational fluid dynamics (CFD) simulation of air flow past a 2D model NACA0012 airfoil at high Reynolds number (Re = 3.0 x 106) at various angles of attack (-10° to 15°). The simulations were undertaken to inform on how the fluid flowed around the airfoil by solving the steady state governing equations of continuity and momentum conservation that are combined with one of three turbulence models Spalart-Allmaras, Realizable k-ε and k-ω shear stress transport (SST). It is observed that the Realizable k- ε eliminates the small separation bubble on the upper surface of the airfoil and delaying separation flow.  Also, for the lift coefficient, CL and drag coefficient, CD investigated in this paper, the predicted data have good agreement with other published data

Numerical Simulation in Transient Flow of Non-Newtonian Fluid in Nozzles

The rheological complexities of non-Newtonian fluids can lead to a variety of difficulties including most importantly changes in viscosity during packaging process. In order to give more understanding in this phenomena, the effect of temperature to the viscosity of chili sauce during packaging is investigated. This paper also presents the influence of three different shape of nozzles to the chili sauce flow behavior during filling time. A transient simulation has been conduct in this work using computational fluid dynamics (CFD) ANSYS CFX 15.0. It was found that viscosity is inversely proportional with temperature drop and time. The filling time also improved when using bigger conical angle of the nozzle. The results indicate the increased in production of the chilli sauce and improve packaging process