Thermal Performance of Steel and Fibre Reinforced Concrete Composite Floor

Talita L Silva,Sandra M Silva,Ricardo Mateus,Isabel B Valente,Maria José Roupar,Joaquim Barros

doi:10.1007/978-3-030-76551-4_18

Abstract

AbstractIn general, steel and concrete composite floors tend to present a reduced functional performance (considering thermal and acoustic conditions), due to their low mass and to the high conductivity of the steel elements. By including components with high thermal insulation capacity in these structural systems, it is possible to maintain the structure lightness and not compromise the thermal performance. Within this work, the analysis is dedicated to a composite floor in which a fibre reinforced concrete (FRC) slab is associated with a concrete filled “U” type steel profile. The fibre reinforcement avoids the use of conventional reinforcement, with significant savings in term of fabrication time. Filler blocks are inserted, composed by thermal insulation material (EPS), between the “U” shaped steel profiles, which act as formwork during the casting phase and, after the concrete hardening, contributing to improve the system´s thermal performance. This system was evaluated through numerical assessment. The analysis enabled to determine the thermal transmittance (U-value) and to identify the critical zones in terms of thermal insulation efficiency. The performance of the proposed solution was also compared to other flooring solutions. According to the results obtained, the proposed composite floor presents a better thermal behaviour than other more traditional flooring systems.KeywordsSteel and concrete composite floorFibre reinforced concreteThermal performanceNumerical analysis

Highlights

Despite columns and beams being smaller when compared to slabs, they create thermal bridges. This is due to the assembly of construction elements that are composed by different materials and due to structural elements that are commonly composed by higher conductivity materials, in comparison to the surrounding construction elements
This work aims to evaluate the thermal performance of a new steel and concrete composite floor
The boundary conditions are the same for all models and the thermal transmittance values obtained in the analysis are close to each other, it can be seen that in models with better thermal performance, the heat flux acting on the building element is lower

Summary

Introduction

The performance of flooring solutions should be evaluated considering their mechanical and functional behaviour, in order to guarantee thermal comfort and structural safety to the users. Structural elements, as slabs, are in many cases in direct and constant contact with the outside environment, and due to their large size, they play a very important role in the heat transfer processes that occur. Despite columns and beams being smaller when compared to slabs, they create thermal bridges. This is due to the assembly of construction elements that are composed by different materials and due to structural elements that are commonly composed by higher conductivity materials (concrete and steel), in comparison to the surrounding construction elements (e.g. walls). Thermal bridges provide heat transfer/loss, but can promote moisture problems. Excess moisture without adequate ventilation can lead to the appearance of bacteria and mold, compromising the users’ health [1]

Objectives

Results

Conclusion