tailieunhanh - Effect of mould type on flexural strength of self-compacting steel fibre-reinforced concrete

Fresh self-compacting steel fibre-reinforced concrete (SCSFRC) of strength class 30 MPa was casted into the small (100x100x400 mm3 ) and large (100x300x400 mm3 ) moulds. The large specimen was splitted into three small identical ones (100x100x400 mm3 ). All of the specimens were subjected to third-point bending in as-cast direction. | Effect of mould type on flexural strength of self-compacting steel fibre-reinforced concrete BÀI BÁO KHOA HỌC EFFECT OF MOULD TYPE ON FLEXURAL STRENGTH OF SELF- COMPACTING STEEL FIBRE-REINFORCED CONCRETE Nguyễn Việt Đức1 Abstract Fresh self-compacting steel fibre-reinforced concrete SCSFRC of strength class 30 MPa was casted into the small 100x100x400 mm3 and large 100x300x400 mm3 moulds. The large specimen was splitted into three small identical ones 100x100x400 mm3 . All of the specimens were subjected to third-point bending in as-cast direction. Flexural strength of SCSFRC obtained from small specimens 100x100x400 mm3 yielded 10 higher than that from large specimens of the same size. While flexural strength defined by the small specimens 100x100x400 mm3 that were cut from the large specimens was almost the same. When pouring fresh SCSFRC into the small mould steel fibres were orientated along with the flow of the fresh concrete due to the wall-effect and the velocity profile. Likely this phenomenon did not occur in the case of large mould. This was the main reason why flexural strength was influenced by mould type. Keywords Self-compacting steel fibre-reinforced concrete fibre orientation mould type wall effect flexural strength. 1. INTRODUCTION heavily reinforced structural members. It has The concept of Self-Compacting Concrete gained significant importance in recent years SCC was proposed in 1986 by Professor Hajime because of its advantages. Besides this concrete Okaruma but the prototype was first developed in has also gained wider use in many countries for 1988 in Japan by Professor Ozawa at the different applications and structural configurations University of Tokyo. SCC was developed at the Sahmaran et al. 2015 . time to improve the durability of concrete Self-compacting steel fibre reinforced concrete structures Okamura amp Ouchi 2003 . Since then SCSFRC combines the benefits of SCC in the various investigations have been carried out and fresh state .