Applied Research, The Preparation Of Self-compacting Concrete In The Bridge Strengthening Works

There are many questions such as difficult vibration or noise caused by vibration during maintaining or consolidating construction by use of ordinary concrete due to small size of section, heavy reinforcements of existed structure. On basis of combination of difficulty of existed structure renovation and characteristics of self-compacting concrete, this paper researched on the self-compacting concrete used in consolidating construction and further applied self-compacting concrete to reinforce Tangjing bridge located in Shenzhen city.The effects of factors such as water to binder ratio, fly ash, high range water reducer, volume fraction of coarse aggregate and etc. on workability of self-compacting concrete were investigated by experiments. Further, the characteristics of mechanical properties including compressive strength, splitting strength, bonding strength, elastic modulus as well as permeability and shrinkage of self-compacting concrete were studied and analyzed in detail. And finally, self-compacting concrete with 40 MPa compressive strength was successfully prepared, which can be used to reinforced construction.Combining experimental results and characteristics of bridge in practice, graded 40MPa self-compacting concrete was chosen to reinforce the Tangjing bridge in the end, which results in casting and vibrating easily and speeding construction progress. Results obtained by loading test and examination on reinforced bridge shows that the quality of concrete is excellent and its carrying capacity and rigidity meets the designed requirements. It follows that self-compacting concrete used to reinforce existed concrete structure has enormous advantage in technology, economics and society aspects.