可水下固化环氧砂浆的制备与性能研究

Preparation and property research of underwater curing epoxy mortar

选用活性稀释剂、低粘度固化剂及疏水改性填料制备了流动度大、疏水性好、力学性能及水下粘结强度优异的可水下固化环氧砂浆。研究了稀释剂、固化剂、填料、偶联剂用量及试验龄期对环氧砂浆力学强度及水下粘结性能的影响。结果表明:当m(E-51环氧树脂)∶m(692稀释剂)∶m(593固化剂)∶m(KH-560偶联剂)∶m(水泥)∶m(硅粉)∶m(细砂)=100∶15∶31∶7.5∶25∶100∶400时,制备的水下固化环氧砂浆性能最优,流动度为265 mm,适用期为75 min,抗拉强度为13 MPa,抗压强度为85 MPa,抗折强度为36 MPa,水下正拉粘结强度为3.0 MPa,界面破坏形式为混凝土内聚破坏,适用于桩基础水下环氧灌浆修复。

Active diluent,low viscosity curing agent and hydrophobically modified fillers were adopted to prepare underwater curing epoxy mortar with high fluidity,good hydrophobicity,good mechanical properties and underwater bonding strength. Effect of the dosage of diluent,curing agent,fillers,coupling agent and trial age on the mechanical strength and underwater bonding strength were discussed. Results showed that the underwater curing epoxy mortar acquired its optimal performance when the mass ratio of the E-51 epoxy resin,692 diluent,593 curing agent,KH-560 coupling agent,cement,silica fume and fine sand was 100：15：31：7.5： 25：100：400. The fluidity is 265 mm,the working time is 75 rain,the tensile strength is 13 MPa,the compressive strength is 85 MPa, the flexural strength is 36 MPa, and the underwater bonding strength is 3.0 MPa with concrete cohesion damage. The prepared epoxy mortar is appropriate for underwater pile foundation repair.