Impact of controlled permeable formwork liner against chloride penetration on the concrete structures

It has become a requirement to enhance the surface quality of concrete structures and their durability. A non-woven formwork called Controlled Permeable formwork (CPF) liner was developed. This CPF liner is permeable to air and water however prevents the getaway of cement and small particles. This paper investigates experimentally the impact of CPF liner on the concrete surface against chloride penetration. The concrete mix contained ordinary Portland cement (OPC) 53, pulverized fly ash (PFA), Micro silica, locally available aggregates, crushed sand, water and superplasticizer. The cylindrical and cubical concrete specimens were cast with impermeable steel formwork (SF) and CPF liner. The cubic and cylindrical specimens were tested at the age of 7 days and 28 days. Compressive strength and Rapid chloride penetration tests (RCPT) were conducted. The concrete cast with CPF liner gives excellent compressive strength 14% more than specimens cast with steel formwork and has acquired better resistance against Chloride penetration. The results show that the concrete sample cast with CPF liner shows 9.98% less charges passed than specimens cast with steel formwork.