CONCRETE CONSTRUCTION ARTICLE                        

recovering concrete after fire alternative

Introduction
When a building structure dominated by concrete is damaged by fire, can material concrete that has been damaged because of a burn be restored to normal strength and remain safe to be used? .. According to the Chairman of the Central Large Power Structure Technology Agency for the Assessment and Application of the technology in his journal in Germany, recovery the strength of concrete burn is very possible.

Nature of Concrete

Concrete has a unique nature, although it has aged, in the concrete, there are grain cement that has not reacted or in other words still intact grain-shaped cement, concrete If the burn range of 500' celcius  to 700 ' celcius,it will increase the damage and decrease the strength, the concrete will also be changed back into the cement.

the level of strength of concrete because of  burned depend on the density and the high temperatures during the fire.  Concrete with a mixture of proportional to the temperature below 300' celcius, ignore it. The effect of the decrease in the strength of concrete is very small.  But if temperature is above than 500' celcius will  decrease the concrete strength .  can reach 40% - 80% of the early strength of concrete.

Recovery strength concrete

In general, when the concrete was damaged as a result of burning or other reasons, people tend to replace them with new concrete. This article presents the construction of an alternative way of repairing the damaged concrete  that is burned with poured it with water.

The reasoning is based on concrete in high temperature will turn again to cement. Furthermore, if the we pour water into the cement, it will be changed back into concrete .. From the results of research carried out, are microscopic, can prove the existence of grain and cement cracks in the concrete. whether the concrete is already settled, there are still inside the grain that has not finished cement reaction and crack hair.  This is what gives hope and made possible the restoration of concrete by poured it with water. There are several methods of sprinkling.  one of that is  use of burlap soaked water, then roll over on the concrete columns like picture below.

 FIGURE 1 :BURLAP SOAKED WATER METHODS

The result rate of recovery strength concrete after water treatment process is capable of approaching 100% of the early strength of the concrete . There are 2 main factors that influence the recovery of  strength concrete after burned .. First quality concrete of the water cement ratio. The small amount of their water content means that the cement that has not reacted more yet.  so that the level of recovery of the concrete will be more  and in high speed. . Secondly. if the duration of the concrete burned is long. consequently, the recovery process is not too good. ( Levi )

created in 161008