Normal Concrete Degradation Due to the Influence of Sea Water Intrusion

The concrete for the Building structure is required to have strong properties in holding the load or working forces. Problems that occur in concrete buildings in the coastal environment of concrete damage caused by the degradation of concrete that interacted with seawater. The durability deterioration of concrete is critical to the durability, safety, and sustainability of infrastructures, especially for offshore concrete structures in marine environments. Real damage caused by seawater, consists of 3 (three) parts: submerged concrete part, concrete part affected by tidal seawater and part of the concrete affected by seawater splashing. The concrete damage discussed in this research is the mechanical degradation of concrete due to the intrusion of seawater in the submerged seawater. Damage can occur in concrete due to the reaction between aggressive seawater that is intruded into the concrete and compounds in the concrete that cause the concrete to lose some of its mass, strength, and stiffness and also accelerate the weathering process. This research used 2 media ponds, where one filled with seawater and the other filled with fresh water. The amount of concrete soaked in seawater as much as 20 specimens, and soaked freshwater (PDAM) as much as 20 specimens. The amount of concrete soaked in seawater as much as 20 specimens, and soaked freshwater as much as 20 specimens. The results of this study indicate that the reduction of compressive strength of concrete due to the intrusion of seawater tends to show a logarithmic graph. Concrete compressive strength will be lost by 50% when the concrete is soaked in seawater for 19,031 days. Normal quality concrete f'c = 25 MPa undergoes mechanical degradation due to seawater intrusion, in this case, the compressive strength of concrete is 12,063% when soaked for 28 days and 16,809% when soaked for 90 days.