MMA基混凝土修补材料的变形、强度及耐久性

Deformation, strength and durability of MMA-based repair materials for concrete

MMA基混凝土修补材料是由甲基丙烯酸甲酯(MMA)和引发剂、增塑剂等合成的高分子聚合物,粘度小且可以通过聚合度的控制进行调整,适宜于细裂纹的修复与修补。研究表明,改性MMA基修补材料收缩接近为0;拉伸强度为46MPa,抗弯强度为90MPa,与砂浆的粘结强度为3 25～9 85MPa;紫外光照射一个月,修补材料的强度可以保持99%;经高温热震和低温热震循环300次后,修补材料的拉伸强度减小为21 56MPa和17 1MPa,弯曲强度减小为40 4MPa和32 5MPa,但仍然远远大于水泥混凝土的强度。

MMA-based repair material for concrete is a kind of polymer made of MMA, initiator, plasticizer and light stabilizer. It is suitable for repairing fine cracks of concrete due to its low and adjustable viscosity. Shrinkage of the repair material is approximately null. Tensile and flexural strengths are 46 MPa and 90 MPa, respectively. The bonding strength of mortar ranges from 3.25 to 9.85 MPa. The flexural and tensile strength can hold 99% under ultraviolet light radiation for one month. The flexural strength were 40.4 MPa and 32.5 MPa after 300 cycles of 15～105 ℃ and -20～15 ℃, respectively. The tensile strength was 21.56 MPa and 17.1 MPa after 300 cycles of 15～105 ℃ and -20～15 ℃ respectively. It may meet the requirement of repair materials for concrete.