Research On High-Fluidity And Super High-Early Strength Concrete

Concrete is the most applied building materials in civil engineering and widely used in many different structures. Relatively the dilapidation of concrete structure is rather universal. Maintenance and consolidation are very important for the concrete structure's serviceability. In this research, the high-fluidity and super high-early strength repairing concrete is prepared though experimental research on quick-repairing materials to cement concrete pavement. This concrete is provided with many properties such as satisfying early traffic opening, benefiting operation, cutting down labor consumption and securing interfacial bond strength. Scientific researches are also carried out on preparing theory, material selection and constructing technics.Materials and their ratio suitable for repairing concrete are studied though optimizing preparing methods and quantities of experiments to meet high fluidity and super high-early strength of repairing concrete. The performances of the concrete are also systemicly researched. Aminobenzenesulfonic acid super-plasticizer is selected though cement paste test, which be provided with high water-reducing property, low slump loss and good compatibility with cement. According to the request of super high early strength, admixture RF is obtained though tests to compare performances of different accelerators and admixtures. Experimental research and analysis are carried out on coarse aggregate's grain-size effect and composite aggregate's bulk-density to take sensitivity of coarse aggregate into account. Bending strength, compressive strength, interfacial bond strength and frost-resistance are also studied and analyzed.Based on indoor research, on-site experiments are conducted on damaged pavement to inspect the performance of repairing concrete. Technical-economical analysis is made considering of the raw and processed materials and repairing economic effect.Theoretic analysis and experimental results illustrate that the performance of high fluidity and super high-early strength repairing concrete is influenced by many factors relative to materials. Only when superplasticizer, admixture RF, early-hardening sulphoaluminate cement and aggregate of suitable size are used, high performance repairing concrete can be prepared with high-early strength and high fluidity and good interfacial bond property.