渗透型结构胶修补混凝土微裂缝研究

Study on the concrete cracks repaired by the permeant adhesive

混凝土开裂是导致结构耐久性降低的主要原因之一。采用新型渗透型结构胶,结合渗透法-无压力灌浆技术修补混凝土微裂缝,重点研究了结构胶及其修补后混凝土的耐久性能。考察了成分、温度、时间等因素对渗透型结构胶性能的影响。通过强度对比,研究了渗透型结构胶与混凝土的粘结性能。采用浸泡腐蚀、冻融循环等方法,考察了修补后的混凝土试件耐硫酸盐腐蚀性能、抗冻性能和抗渗性能等。试验结果表明:温度和活性稀释剂是影响结构胶粘度的主要因素,固化剂和活性稀释剂用量是影响强度的主要因素;修补后试件的强度可提高24%～120%,修补后的混凝土试件经硫酸盐加速腐蚀强度增长3%～26.2%;与此同时,其抗冻性能和抗渗性均有所提高。为简化混凝土裂缝压力灌浆技术以及渗透型结构胶技术的工程应用奠定了必要的理论依据和试验基础。

Concrete cracks is one of the most important reasons for deteriorating the durability of concrete.A kind of new permeant adhesive and a new technique called permeation-nonpressure technique are introduced for repairing the tiny cracks.The viscosity,strength of the permeant adhesive are tested,respectively.The adhesion between the permeant adhesive and concrete is studied by the method of comparing strength.The sulphate attack,freeze-thaw resistance and impermeability of the repaired concrete are discussed by the method of immersion corrosion and freeze-thaw cycles.It is shown that temperature and reactive diluents are important factors in viscosity of the permeant adhesive.Curing agent and reactive diluents are important factors in strength.The strength of the repaired concrete can increase 24% to 120%.The strength of the repaired concrete which is immersed in sulphate increases 3% to 26.2%,while the freeze-thaw resistance and impermeability of the repaired concrete are better.The above provide the theoretic and experiment foundation for simpling the pressure grouting technique of concrete repairing and application on the permeant adhesive.