This paper investigates the possibility of utilizing burnt clay brick waste (CBW) as a partial replacement for natural sand (NS). The natural sand was replaced with CBW at five levels: 0%, 25%, 50%, 75%, and 100%. The physical properties, mechanical strength, shrinkage, porosity, and decay of compressive strength due to elevated temperatures (after exposure to 20, 250, 400, and 600 °C) were performed. The results show that the workability and dry density of mortar decrease as the CBW content increases. The mechanical strength of the mortar increases up to 50% replacement level of NS with CBW. The increase represents 17–25% for compression, 25–31% for tensile, and 5–31% for flexural strength relative to the reference mix (100% NS) at all curing ages (7, 14, 28, and 60 days). Furthermore, results show that the shrinkage increases with an increase in the content of CBW. A decreasing trend of porosity was observed for the mortar made with up to 50% CBW, which is in good agreement with the mechanical strength of mortar. Nevertheless, the residual compressive strength of mortar decreases for all mixes at elevated temperatures, and it was more pronounced for the higher temperatures. This study demonstrates that up to 50% of CBW can be used as fine aggregate in mortar since it enhances the mechanical and durability performances.

本文研究了利用燃烧的粘土砖废料（CBW）替代天然砂（NS）的可能性。天然砂被CBW替换为五个级别：0％，25％，50％，75％和100％。进行了物理性能，机械强度，收缩率，孔隙率以及由于高温（在暴露于20、250、400和600°C之后）导致的抗压强度下降。结果表明，随着CBW含量的增加，砂浆的可加工性和干密度降低。砂浆的机械强度提高了CBW替代NS的50％。在所有固化年龄（7、14、28和60天）下，相对于参考混合物（100％NS），压缩量的增加代表压缩比的17-25％，拉伸强度的比重为25-31％，弯曲强度的比重为5-31％。 。此外，结果表明，收缩率随CBW含量的增加而增加。对于CBW高达50％的砂浆，观察到孔隙率下降的趋势，这与砂浆的机械强度非常吻合。然而，在高温下，所有混合物的砂浆残余抗压强度都会降低，而在较高温度下则更为明显。这项研究表明，高达50％的CBW可以用作砂浆中的细骨料，因为它可以提高机械性能和耐久性能。并且对于更高的温度更加明显。这项研究表明，高达50％的CBW可以用作砂浆中的细骨料，因为它可以提高机械性能和耐久性能。并且对于更高的温度更加明显。这项研究表明，高达50％的CBW可以用作砂浆中的细骨料，因为它可以提高机械性能和耐久性能。