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Short- and Long-term Performance of Fibre-Reinforced Cement Proffi ififi le Sheets Containing Asbestos and Non-asbestos Materials 84 The Journal of the Royal Institute of Thailand Vol. 37 No. 4 Oct-Dec 2012 controlled at the temperature of 70±5˚ C . using the ceramic heaters. After subjected to 25 cycles, each specimen was inspected visually for cracks, delamination, and other defects on the surface of the specimens. Further test was also carried out to determine the bending test of the tiles subjected to heat-rain cycle. The testing results were expressed as the breaking load per meter width. The technique for analysis of variance (ANOVA) was conducted using the PASW statistics 18 program for finding the contribution of factors in the measurements of the tests. Significant level (α) used in the studies was set at 0.05. Results and Discussion Major compounds of cement present in tiles The quantities of calcium, silica, and alumina which are the major compounds of cement present in each type of tile are shown in Figure 1. It could be seen that the percentages of calcium and alumina for all four types of tile were insignificantly different. The green tile had the silica content slightly higher than the others. However, the significant levels of the statistical analysis for the percentages of calcium, silica, and alumina were 0.23, 0.08, and 0.89 respectively. It could, therefore, be concluded that the major compounds of cement present in each type of tile were not statistically different, with a two-sided p-value higher than 0.05. Shape of reinforcing fibre Figure 2 shows the shape of fibre containing in blue and brown tiles. It was found that the shape of fibre was short and may be present in the form of webs. On the contrary, the shape of fibre containing in red and green tiles was found to be discrete elements randomly dispersed (see Figure 3). Then it may be implied that blue and brown tiles had similar type of fibre which were different from red and green tiles. Dimension of tiles The individual thickness of the tiles being investigated was found to be approximately constant throughout the width of the profile. The results of mean thickness for all types of tiles are shown in Figure 4. It was found that the red tiles had the thickness of the sheets slightly more than the other types. This was also confirmed by the statistical analysis of variances for all of the