Pull-out performance of T-stub end plate connected to concrete filled thin-walled steel tube (CFTST) using lindapter hollo-bolts / Nazrul Azmi Ahmad Zamri … [et al.]

The application of concrete filled steel tubes (CFSTs) as composite members has widely been used around the world and is becoming popular day by day for structural application especially in earthquake regions. This paper indicates that an experimental study was conducted to comprehend the behaviour of T-stub end plates connected to concrete filled thin-walled steel tube (CFTST) with different types of bolts and are subjected to pullout load. The bolts used are normal type bolt M20 grade 8.8 and Lindapter Hollo-bolt HB16 and HB20. A series of 10 mm thick T-stub end plates were fastened to 2 mm CFTST of 200 mm x 200 mm in cross-section. All of the specimens were subjected to monotonic pull-out load until failure. Based on test results, the Lidapter Hollo-bolts showed better performance compare to normal bolts. The highest ultimate limit load for T-stub end plate fasten with Lindapter Hollo-bolt is four times higher than with normal bolt although all end plates show similar behaviour and failure mode patterns. It can be concluded that T-stub end plate with Lindapter Hollo-bolt shows a better performance in the service limit and ultimate limit states according to the regulations in the design codes

Mechanical properties of reinforced concrete beam with recycled coarse aggregates / P. J. Jaua Junior, C. Petrus and J.D. Nyuin

The significant increment of waste concrete in recent yearsthat is happening worldwide has a tremendous consequence to the environment. Recycling concrete wastes will reduce the amount of waste as well as save natural resources, thus help promote green and sustainable development. Thisstudy presents an experimental investigation dealing with the development of green concrete using recycled concrete waste (RCWA) as coarse aggregate replacement materials. The mechanical properties of reinforced concrete (RC) beams in terms of its compressive and flexural strengths were determined. The main parameter considered is the percentage of RCWA in the concrete design of RC beams that ranges from 0% to 50%. From the test results, it was observed that the flexural strength and the compression strength decreased as the percentage of recycled concrete waste aggregate used increased. Generally, the flexural strength of RC beam with RCWA can be 5% to 12.4% lower than that of conventional concrete made with natural course aggregate