engleski

TRIAL DESIGN AND MODEL TESTS ON REACTIVE POWDER CONCRETE (RPC) ARCHES

Arch is an ideal structure for concrete with high compression strength and limited tensile strength. It may be favorable to use ultra-high strength concrete, such as Reactive Powder Concrete (RPC), to reduce the structural dead-weight and facilitate the construction. In order to build an RPC arch bridge in China, trial design, model tests, as well as research on RPC material have been carried out. In the trial design, the Wanxian Yangtze River Bridge with a main span of 420m is taken as prototype. Analysis results show that by utilizing RPC much thinner cross section elements can be adopted due to its high performance and strength, hence effectively reducing the self- weight of the arch ring and consequently the internal forces caused by the self-weight and also furthering a notably easier construction. In the experimental research, the behavior of two RPC arch models were tested with concentrated loads at quarter-span. Load-displacement curves, strains, cracks, failure modes and ultimate load-carrying capacity of the arches were analyzed and compared with results obtained on reinforced concrete (RC) arch models. Experimental results show that the behavior of RPC arches is similar to that of RC arches. The RPC arches also fail due to the mechanism formed by four plastic hinges caused by cracks in tensile areas. But the initial crack load, reinforcement yielding load and ultimate carrying capacity of RPC arches are 2 to 3 times larger than those of RC arches ; and the largest crack width in RPC arches is only forty percent of that of RC arches. In conclusion, results of our preliminary research seem to indicate that it is possible to use Reactive Powder Concrete (RPC) in long span arch bridges.

Reactive Powder Concrete (RPC); Trail design; Arch model; Experiment

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