Sustainability in concrete structure has been developed rapidly for ensuring the requested for a new thinking about construction by concrete elements. This paper deals with using buddle using polyethylene terephthalate PET bottles and steel meshes for fabricating and modeling one way RC voided slab. That is very useful to reduce the weight of slab, also reduced the wastes in same time. For both the voided and solid ones, the load-displacement curves were almost identical from beginning until the load reaches ultimate stages, where the increasing in depth of voided slab showed higher strengths and lower displacement at same load level.

When glass fibre-reinforced polymer (GFRP) bar splices are used in reinforced concrete sections, they affect the structural performance in two different ways: through the stress concentration in the section, and through the configuration of the GFRP–concrete bond. This study experimentally investigated a new method for increasing the bond strength of a GFRP lap (two GFRP bars connected together) using a carbon fibre-reinforced polymer (CFRP) sheet coated in epoxy resin. A new splicing method was investigated to quantify the effect of the bar surface bond on the development length, with reinforced concrete beams cast with laps in the concrete reinforcing bars at a known bending span length. Specimens were tested in four-point flexure tests to assess the strength capacity and failure mode. The results were summarised and compared within a standard lap made according to the ACI 318 specifications. The new method for splicing was more efficient for GFRP splice laps than the standard lap method. It could also be used for head-to-head reinforcement bar splices with the appropriate CFRP lapping sheets.

No abstract

The enhancement of concrete structures’ performance can easily be achieved. However, the main challenge is how to achieve this performance with respect to the economy and sustainability. The aim of this research is to examine the flexural strength, ductility, stiffness, and toughness of RC hollow one-way slabs that are voided by plastic bottles. A new technique of hollowing has been used in this work, where a steel mesh tube was prepared previously and filled manually with blank waste plastic bottles to form a light tube. This technique has some advantages including ease of installation and adequate bonding for the main steel reinforcements. Five RC one-way slabs were cast and tested in the lab to investigate some variables: the presence of hollow, the ratio of reinforcement, and slab thickness. Briefly, a new technique for voids enhances the flexural behavior with less concrete and weight. The ductility is increased by about 100% for the voided specimens for the same section’s thickness. Also, the rotation in supports had been reduced by about 30% when the thickness of voided slab was increased by about 15%.