Bending and Shear Behaviour of Waste Rubber Concrete-Filled FRP Tubes with External Flanges

An innovative beam concept made from hollow FRP tube with external flanges and filled with crumbed rubber concrete was investigated with respect to bending and shear. The performance of the rubberised-concrete-filled specimens was then compared with hollow and normal-concrete-filled tubes. A comparison between flanged and non-flanged hollow and concrete-filled tubes was also implemented. Moreover, finite element simulation was conducted to predict the fundamental behaviour of the beams. The results showed that concrete filling slightly improves bending performance but significantly enhances the shear properties of the beam. Adding 25% of crumb rubber in concrete marginally affects the bending and shear performance of the beam when compared with normal-concrete-filled tubes. Moreover, the stiffness-to-FRP weight ratio of a hollow externally flanged round tube is equivalent to that of a concrete-filled non-flanged round tube. The consideration of the pair-based contact surface between an FRP tube and infill concrete in linear finite element modelling predicted the failure loads within a 15% margin of difference.

Experimental Behavior of Composite Infilled & Encased Column by using MSAND, Metakaolin & Recron Fibre

In this analysis, take a look at on compressive strength of composite infilled and encased columns were done. Compressive strength of hollow, tubular and encased typical section in addition as Msand, silcafume, metakaolin & recorn fiber concrete-filled tubes were decided. Cross-section, compressive strength, and mode of failure of the column to be explored. The circular section and square section were selected for this research. The association between the load, and the later displacement at the mid-tallness, base, and top of the sections inside the bearing of each the durable and powerless axes, and furthermore the connections of burden versus complete the process of shortening for each example was reliably recorded. It completely was discovered that the load carrying limit differs with importance to the cross-section of the specimen, compressive strength of the infill material. The investigation is carried out for the water-cement ratio of 0.5% for in composite column of size 150 × 150 × 1800 mm and diameter of 1800 mm of square and circular section. Then the specimens are to be tested on 7th day, 14th day and 28th day. The circular specimens having higher load-carrying capacity than square specimens. Msand, metakaolin and recron fiber waterproof agent concrete infilled in and encased steel tubes show 5% to 15 % more strength than typical control concrete-filled steel tubes.

Cyclic Performance Evaluation of Hollow Structural Section (HSS) and Concrete-Filled Tube (CFT) Braces

Hollow structural sections (HSS) are widely used as braces because they have inherent axial, flexural, and torsional capacities. Delaying or preventing local buckling is accomplished by concrete infill in HSS braces to improve their cyclic response heavily relying upon three key parameters: (1) presence of concrete infill, (2) width (diameter)-to-thickness ratio, and (3) length-to-width (diameter) ratio impress the cyclic response of HSS braces. Nevertheless, it is not clear that based on which parameter, concrete infill can significantly enhance the peak compressive strength and energy dissipation capacity of HSS braces. This paper aims to investigate this concern while presenting a numerical study on the cyclic response of 120 HSS and Concrete-Filled Tubes (CFT) braces with various geometric characteristics. Square and circular cross-sections, 10, 12, 13.33, 20, 30, 33.33, and 50 width (diameter)-to-thickness ratios and 10, 15, 20, 25, 30, 37.5, 45, 50, 75, and 112.5 length-to-width (diameter) ratios are selected for the numerical investigation. Obtained results indicated that concrete infill can increase peak compressive and post-buckling strengths and energy dissipation capacity of HSS braces around 81%, 43%, and 73%, respectively. It was found that concrete infill and parameters of width (diameter)-to-thickness ratio and length-to-width (diameter) ratio influence the cyclic response of HSS braces differently. On the other hand, concrete infill noticeably enhances the peak compressive strength of HSS braces with larger values of width (diameter)-to-thickness ratio and energy dissipation capacity of such braces with lower values of length-to-width (diameter) ratio.