Author : Flah Hassan, Nada
Effect of Adding Styrene Butadiene Rubber Admixture (SBR) on Concrete Properties and Bond Between Old and New Concrete
journal of kerbala university,
2007, Volume 3, Issue 4, Pages 63-74
The study involves the effect of adding cempatch SBR ( Styrene- Butadiene – Rubber) emulsion to the followings:
1- Cement mortar with different dosages of SBR ( 10 %, 25%, 35% ) by volume of water. Compressive strength of this mortar was tested at ages ( 7, 28, 60 ) days. Initial and final setting time were also recorded.
2- Concrete mix 1 : 2 : 4 with 0.45 water to cement ratio by weight, and SBR in dosages of (10 %, 2 5%, 35 %)by volume of water . Compressive strength in ages ( 7, 28, 60 ) days was tested, also absorption, slump loss with time and flexural strength were also measured.
3- SBR was also used as bonding mortar layer between old and new concrete layers, the compressive strength and flexural strength of bonded samples were tested.
Adding SBR emulsion to cement mortar affects compressive strength negatively at all ages. Initial and final setting time decrease with increasing the dosage of SBR.
The using of SBR emulsion as admixture for concrete mix affects compressive strength with decreasing at early ages ( 7 days ) and increased at later ages. It also reduces; the absorption of concrete and slump loss with time and increase the flexural strength.
The use of SBR as bonding layer showed increasing in compressive and flexural strength of the bonded samples compared with samples having old and new concrete without bond layer.