Research On New Cement Based Repair Motar

Repair and reinforcement of constructions has been an important field in Construct. It can not be undifferentiated that properties of repair materials considering the complexity of factors resulting deterioration of constructions and environment of repairing. Hence, it has great significance to explore repair materials with different properties in order to adapt to varied repairing situation. Based on the concepts of"compatibility"and"system design in repairing the repairs", the paper combined the properties of inorganic and organic repair materials, which not only assured the high bond strength of repair materials, but the compatibility of the repair materials and based materials, as the comparing low proportion of organic components.The work exerted"both added"technic of superplasticizer and mineral admixtures, used grinded blast slag as the main admixture, added with lithium slag and limestone etc. and modified the repair materials'properties by some proper agents(accelerating agents, polymer-dispersion additives, expanding agents etc.). By exerting common technics and curing ways, the compound effects of different mineral admixtures and influence of compound admixtures, agents etc. on workability, mechanical properties, durability of the repair mortars had been researched.Two kinds of repair mortars with different properties had been prepared on the condition of lab, which can be self-leveling. So they could be used in the environment of high fluidity required, such as dense steel zone, thin members, complicated form and structures, road surface repairing. Besides EJ-1 can be used in the repair of bridge and road surface which require high flexible strength. EJ-2 can be used in the environment of comparing low compressive strength but good tenacity required.Using bond shearing strength as appraisal index to evaluate the bond properties between new and based materials, four kinds of interfacial agents had been prepared which had different effects on the repair materials. Yet the two kinds of repair materials both are suitable to interfacial agents of M2 and M3 which are added with lithium slag and expansive agents respectively. Interfacial agent M2 is more effective than M3 to the repair mortars .SEM and XRD trials have showed that the hydrate of interfacial agent M2 added with lithium slag admixture appeared shape of disorder fibers, fine AFt, which was beneficial to the bond of interfacial zone(IZ); but interfacial agent M3 added with expansive agent had big crystals, favoring direction CH, which were adverse to the bond of IZ.At last, the influence of sorts, proportion of mineral admixtures and agents on durability of the repair mortars. The trials showed that the repair mortars prepared had been a bit expansive, good resistance of chlorine ion pervision and erosion of sulphate.