Thursday, May 3, 2007

FEATI University, Science and Technology Expo 2005

Substitute for Epoxy Concrete Crack Injection
(Best Department Entry, FEATI University, Science and Technology Expo 2005)
By
Mr. Moniel Santos (Researcher)
Engr Alex H. Balaan (Adviser)


The most commonly used seen in a vertical structure are the so-called hairline cracks. These cracks maybe found in beam, column and walls due to cement settings, additional loading and low seismic activities or tremors. These can cause exposure of reinforcing steel bars in the atmosphere which may produce an oxidation reaction which may later on turn into rust. The cement may also expand and become hallow which can cause serious damages the structure.
The most popular material used nowadays to seal the cracks and prevent exposures of reinforcing steel bars is the epoxy crack injection. When the said injection is applied, it hardens the structure with a nominal strength equal to a concrete w/c is 300 psi. however, this procedure is quite very costly.
Therefore, the researcher find an alternative substances which has the same productive effect, but nonetheless, economical. Studies show that in the old time, people used a strong liquid adhesive that came from animal skins and interterm based on this observation, the researcher put into test a solids form mixture of protein based carabao skin and added water. It eventually blended and resulted into a viscous liquid state similar to oil.
The researcher moved on to another widely used glue which is the pearl glue. It is also an animal based protein. The researcher added water, bring it to a certain boiling temperature and set aside. It exhibited an elastic properly as hard as the first substance, but much stronger than the previous one. However, it cannot be injected due to its viscosity. The workability is low and when diluted, it loses its strength. It also took a longer time to dry.
To become up with our desired goals, the researcher decided to combine the two mixture in a certain proportion and performed the same procedures with precise measurement and exact temperatures. The resulting mixture exhibited or well-defined liquid state. The workability is good. Furthermore, when it was set aside, it become hard which maybe similar to a concrete. However, to make it workable, it should be noted that exact measurements must be observed from cooling, otherwise, it will become viscous and later on, will only become a glue. If set aside, it will be hardened and if reused, it will be weaken.

Reference: FEATI University Science and Technology Expo 2005 Souvenir Program

Tagged : FEATI University, College of Engineering, Civil Engg. Dept.

No comments: