New concept of construction method for foundations system using cold-formed steel section

Abstract

Pad footing foundations are typically built using traditional method of reinforced concrete by utilising wooden formwork. This wooden formwork encounter problems such as the formation of rectangular shape which is not consistent, the use of timber which is not environmental friendly and not contributed to the strength, the excessive use of labour to construct and the difficulty to cast during raining season. As a result, this method tends to slow down the construction time and affect the quality of the product. Thus, an approach to apply the concept of pre-fabrication into the construction of pad footing foundation has been introduced using cold-formed steel (CFS) lipped channel sections to replace both the timber as formwork and steel bars as reinforcement. The use of CFS in pre-fabricated pad footing foundation has not been established yet. In order to investigate the structural behaviours of such pre-fabricated pad footing foundation, eighteen specimens were tested consisting of 6 specimens of typical footings, 4 specimens of CFS with A10 wire mesh as reinforcement, and 8 specimens of fully CFS with thickness varies from 150 mm to 200 mm, and with length varies from 1 m to 1.75 m. All specimens are checked for punching shear, longitudinal shear, and bending moment. The experimental and theoretical calculations were carried out and compared. The results showed good agreement between the experimental and theoretical values with flexural and shear strength are much higher than the conventional pad footing. Therefore, it can concluded that the proposed pre-fabricated pad footing foundation using CFS lipped channel sections is suitable to be used as pad footing.