A comparative study between the theoretical and practical implementation of a one-way hollow brick slab

Abstract

Abstract:

This paper included a comprehensive comparison between the theoretical part according to scientific references and according to the American ACI code, and specifically included mainly the strength of concrete considered during the design stage, how to lay hollow bricks , reinforcing steel and the rest of the instructions, as well as how to design a one-way hollow brick slab and compare the theoretical part with practical implementation through investigations of three sites in Tripoli, including the strength of concrete and various works in execution, in addition to the dimensions of ribs, the amount of reinforcing steel and the structural drawings for roofs were identified.

What is being worked in Libya, whether in the implementation of private or public sector projects, and what the first and second  researchers noticed is that the concrete is poured for the roof slab in two stages, whether the pouring is used with manual mixers on site or those in which the pump and mobile concrete mixers are used, the first stage is poured up to the upper surface of hollow bricks, and the upper layer is the one above the first, where an extra water is added to the mixture to increase the workability, and all we know that the upper layers of concrete above the neutral axis is the most important for the design purposes .

Samples were taken from several sites in Tripoli and several differences were found between the design and implementation, including the high w/c ratio in the upper layer, which weakens the compressive strength of concrete, as well as some damaged materials that are not suitable for use in the slabs, and the failure to maintain design spaces such as the spaces between the stirrups.