STRUCTURAL PERFORMANCE OF COMPOSITE REINFORCED CONCRETE BUBBLED ONE WAY SLABS A

Abstract

Abstract Slab is very important structural member and usually take high percentage of total weight of building therefore, many attempts have been conducted in order to reduce the dead weight of slabs and most of these researches focus on the traditional reinforced concrete slabs and composite reinforced concrete slabs while there are no researches conducted on reducing self-weight of composite slabs with plastic bubbles. The composite one-way slab with plastic bubbles (One-Way Composite bubbled slab system) is a developed type of slabs in which used recycled plastic bubbles in one way composite slab in order to reduce the self-weight of slab. This study presents experimental investigation to study the structural performance of composite reinforced concrete bubbled one way slabs, where twelve specimens of composite one-way slabs with dimensions (1850mm x 500mm x110mm) have been evaluated. All the composite slabs specimens divided into four groups according to presence or absence of shear connectors, also depending on presence or absence of plastic bubbles and diameter of plastic bubbles (70mm and 86mm). Each group consists of three specimens of composite slabs which are different in geometry of profile steel sheet (trapezoidal shape, triangle shape and T-shape). The composite slabs specimens tested under two-point load to obtain the ultimate load capacity, vertical deflection response, slip between steel sheet and concrete, strain development in concrete and steel sheet, toughness index and energy absorption. II The test results show that other types of geometries of profile steel sheets can be used such as (T-shape and Triangle shape) instead of the trapezoidal shape (traditional shape). These types have better results in term of the ultimate load and structural behavior. The adding shear connectors to the composite slabs with (Trapezoidal shape and Triangle shape) increase the ultimate load capacity by (22.2% and 17.8%) respectively and decrease deflection as compared with the same load while effect of adding shear connectors to the composite slab with T-shape is very little or can be neglected. It has been found that the composite bubbled slabs, (with diameter 70mm) give an ultimate load close to composite slabs without bubbles, except the composite bubbled slab with a trapezoidal shape shows a decrease in the ultimate load by (10.9%). Increasing the diameter of bubbles from 70mm to 86mm leads to increasing the ultimate load capacity of composite slabs with trapezoidal and triangle shapes by (10.2% and 18.1%) respectively, and decreasing the ultimate load of T-shape by (6.2%). The proposed one-way composite bubbled slab consider sustainable section and has important contribution to construct environmentally friendly buildings where the sustainability analysis shows that the CO2 emission and embodied energy can be reduced up to 13.8% and the raw material by about (6.75% to 14%) by using the composite bubbled slab.