Analysis of Deformation and Stresses of a Lightweight Floor System (LFS) under Thermal Action.

Jacek Karpiesiuk,Tadeusz Chyży

doi:10.3390/ma14195727

Abstract

The lightweight floor system (LFS) with a heating coil is one of many types of radiant heating systems. It differs from most of the others, as it has a much higher thermal efficiency at low flow temperature. To verify whether adhesive mortars can safely connect the ceramic floor with the insulating substrate, the deformations and stresses values of all light system layers under thermal action should be checked and compared to their maximum strengths. For this purpose, an LFS test field was conducted using the strain gauges and digital measurement techniques, and floor displacements and deformations were determined. The results obtained from the tests were confirmed by finite element method calculations. It was also found that the stress of each floor component was much lower than their strength. This proves that the LFS with a heating coil, without metal lamellas, meets the safety regulation for use. The results of the analysis can be useful in the design of heated/cooled LFSs.

Highlights

Lightweight floor systems (LFSs) have been studied extensively, especially to determine comfort characteristics and heat flux density
In this type of experiment, it is not sufficient to read the results coming directly from the recorder. These are influenced by temperature, which changes the length of material layers, as well as indications of strain gauges undergoing deformation
The change in material deformation recorded on the strain gauges should be taken into account by correcting the measurement results obtained from the recorder

Summary

Introduction

Lightweight floor systems (LFSs) have been studied extensively, especially to determine comfort characteristics and heat flux density. In these tests, as the thermal insulation, expanded polystyrene (EPS) plates, with a compressive strength at 10% deformation of 200 kPa, and extruded polystyrene (XPS) plates, with a compressive strength of 300 kPa, were used (Figure 2). The results of experimental tests and computer calculations made with the use of the finite element method were compared and the stresses verified The purpose of these tests and analyses, taking into account the maximum standard deflections, service loads, and thermal action of the floor, was to confirm or deny that the developed lightweight floor model without a screed layer and without aluminium lamellas, with a built-in coil, meets the strength and deformation conditions and can be used safely

Materials and Experimental Methods

Conclusions

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