Investigation into the flexural characteristics of cold formed steel filled with rubberised concrete

Worldwide environmental concerns regarding large stockpiles of waste tyres have led to investigations into alternate options for the disposal of waste tyres. One possibility to decrease the environmental burden created by waste tyres is for the building and construction industry to incorporate recycled rubber into concrete. There are various issues that occur when introducing recycled rubber into concrete which have been identified in prior investigations. The main issues identified include the difficulty of making a homogeneous concrete mixture with rubber and the loss of compressive and flexural strength with higher rubber volumes. This dissertation investigates these issues and provides a thorough insight into crumb rubber concrete (CRC) and its characteristics. Many previous investigations have introduced various treatment methods in order to improve the compressive strength of CRC. An already established method of rubber treatment using sodium hydroxide (NaOH) has been adopted in this investigation. NaOH treatment is considered the best and most widely used treatment method for rubber particles and will serve as a good comparison for other treatment methods investigated in this study. In addition to NaOH treatment, a relatively new method of water treatment has been investigated. This method involves soaking rubber particles in water for a set period of time. A number of fresh and hardened concrete tests were performed using the new treatment method with varying contents of crumb rubber. The effectiveness of both treatment methods listed in this investigation has been determined by comparing the strength characteristics of treated rubber concrete with untreated rubber concrete. Within this study it was discovered that NaOH treated samples displayed 16% higher compressive strength when compared with untreated rubber samples. Water soaked treated samples displayed 26% higher compressive strength when compared with untreated rubber samples