Abstarct
This paper reports the results of an experimental and analytical study to investigate the mechanical properties of unstressed foamed concrete exposed to high temperatures. Two densities of foamed concrete, 650 and 1000 kg/m3, were made and tested with additional tests being performed on densities of 800, 1200 and 1400 kg/m3 for additional data. The experimental results consistently demonstrated that the loss in stiffness for foamed concrete at elevated temperatures occurs predominantly after about 90 _C, regardless of density as water expands and evaporates from the porous body. From a comparison of the experimental results of this research with a number of predictive models for normal strength concrete, this research has found that the mechanical properties of foamed concrete can be predicted using the mechanical property models for normal weight concrete given that the mechanical properties of foamed concrete come from Portland Cement CEM1
Contents
1. Introduction
2. Experimental setup
2.1. Specimen preparation
2.2. Heating of specimens
2.3. Test overview
2.4. Compression test setup
2.5. Three point bending test setup
2.6. Porosity measurements
3. Results and discussion
3.1. Effects of high temperature on foamed concrete density
3.2. Effect of high temperature on porosity of foamed concrete
3.3. Effects of high temperature on compressive strength of foamed concrete
3.4. Effects of high temperature on compressive stress–strain relationship of foamed concrete
3.5. Effect of high temperature on modulus of elasticity of foamed concrete in compression
3.6. Effects of high temperature on foamed concrete failure mode in compression
3.7. Effects of high temperature on flexural tensile strength of foamed concrete
3.8. Effects of temperature on flexural tensile modulus of foamed concrete
3.9. Additional mechanical properties test results
4. Models for foamed concrete mechanical properties
4.1. Prediction of mechanical properties of foamed concrete at ambient temperature
4.2. Prediction of mechanical properties of foamed concrete at elevated temperature
5. Conclusions