Comparative analysis of chemical composition, mechanical performance, workability, and sustainable characteristics of cementitious tile adhesives and cement mortar

This study provides a detailed experimental evaluation of three commercially available cementitious tile adhesives (K1, M1, and S1) in comparison with traditional cement mortar (C). The investigation covered microstructural, chemical, mechanical, and physical properties. Material composition and microstructure were analyzed using XRF, XRD, SEM, and EDS, while workability was assessed through flow, density, slip resistance, and open-time tests. Mechanical performance was evaluated by tensile adhesion strength, tensile strength, compressive strength, stress–strain behavior, and flexural strength. Results showed that the cement mortar exhibited the highest compressive, flexural, and tensile strengths, reflecting its dense microstructure and standard Portland cement composition. However, it demonstrated poor workability, with zero adhesion strength and slip resistance, rendering it unsuitable as a tile adhesive. All three commercial tile adhesives met EN standards for open time, slip resistance, and tensile adhesion strength, though their mechanical strength was lower than that of the mortar. This study conducts a comparative evaluation of cementitious tile adhesives and traditional cement mortar in terms of chemical composition, mechanical performance, workability, and sustainability. Results show that while cement mortar achieved higher compressive and flexural strengths (up to 47.89 MPa and 9.12 MPa at 28 days, respectively), the S1 adhesive demonstrated superior tensile adhesion strength after heat aging (1.77 MPa) and good overall performance. The findings reveal a clear trade-off between mechanical strength and adhesion, indicating that optimized formulations, such as S1, offer promising potential for applications requiring a balance of structural integrity and enhanced microstructural properties. Among them, S1 performed best, achieving higher compressive strength, flexural strength, tensile adhesion, and microstructural densification, which can be attributed to its higher SiO 2 + SO 3 content and silicate-rich phase. K1 showed the weakest overall performance. Overall, the findings confirm that while cement mortar excels in mechanical performance, commercial tile adhesives are purpose-designed to provide essential bonding, slip resistance, and workability for tiling applications. S1, in particular, demonstrated superior balance between mechanical stability and adhesion, underscoring the role of tailored formulations in construction materials.