Coal rejects concrete (CRC) made of the industry by-product generated during the mining preparation and washing procedure is usually regarded as the alternative to natural aggregate concrete (NAC). To improve the low strength and brittleness of CRC, this paper presents a new structural form, termed fibre-reinforced polymer (FRP)-confined CRC (FCCR) column. The most attractive feature of the FCCR column is its cost-effectiveness and environmental-friendly, because that the aggregates of infilled CRC are all from sieved coal rejects without any more artificial crushing process. To obtain the further understanding on the behaviour of FCCR column, a total of 10 hybrid columns, consisting of 6 FCCR and 4 FRP-confined NAC (FCNA) columns with a diameter of 200 mm and a height of 450 mm, have been prepared and tested. The main variables tested in the present study covered the FRP thickness and the concrete strength. Test results showed that FCCR columns obtained the similar mechanical performa
This paper introduces a novel standing support incorporating fibre-reinforced polymer (FRP), termed FRP tubular standing support (FTSS). The exterior container of FTSS is the small rupture strain (SRS) GFRP tube wrapped with ultra-high molecular weight polyethylene (UHMWPE) FRP jacket with large rupture strain (LRS), while the infill is the coal rejects based backfill material (CBM). The CBM is made of industrial by-product (i.e. coal rejects) and high flowable cementitious grout material, leading to some environmental and economic benefits when it is used in underground mines. Test variables included the type of coal rejects (i.e. screened and unscreened), the thickness of SRS FRP tube (i.e. 1.5 mm and 3.0 mm) as well as the thickness of LRS FRP jacket (i.e. 2-ply, 3-ply and 4-ply). Test results showed that both the load carrying capacity and deformation ability of CBM in FTSS have been significantly enhanced attributed to the confinement provided by exterior FRP container. Existing s