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Reinforced concrete structure, reinforced rust, corrosion products volume becomes 2-4 times, reinforced concrete around would be a squeeze pressure due to the volume expansion of the corrosion products, such extrusion pressure called Expansion Force, the rust expansion force, reinforced concrete around the rust expansion stress occurs. With the increase in the rate of steel corrosion, concrete rust expansion by force will more and more, eventually leading to the protective layer of concrete in tension cracking. The protective layer to crack, it will accelerate the corrosion of reinforcement, will further exacerbate the expansion of the cracks, eventually leading to structural damage, serious impact on the durability of concrete structures. Thus reinforced concrete structure due to rebar corrosion due to cracking of the protective layer has important significance. Lang Cairn Tunnel offshore tunnel Zhuhai eye research background, to simulate the temperature expansion is applied to numerical simulation of reinforced reinforcement rust expansion to study the mechanical behavior of reinforced concrete members and tunnel lining structure under the Expansion Force mainly to the following conclusions: 1, by the calculation that the tensile strength of the concrete, the thickness of the protective layer, and the diameter of the rebar affect the size and reinforcement of the protective layer of rust expansion stress cracking corrosion rate. The tensile strength of concrete is the greater, the greater the thickness of the protective layer, reinforced the smaller the diameter of the steel corrosion rate, the greater the protective layer cracking. 2, in the case of the same steel corrosion rate, the various parts of the lining is corroded expansion force of the impact. Corner rust expansion tensile stress, followed by invert vault the smallest arch back and the arch. Therefore to produce rust Cracks in the first corner of the tunnel under the role of corroded expansion force, then invert and vaults. Steel corrosion, with the increase in the corrosion rate, crown settlement amount is also increasing. Corrosion of reinforcement has little effect on the value of the crown settlement only consider steel corrosion stainless inflation, the corrosion rate from 0% to 30% of the process, the crown settlement amount total increase of 1%; consider reinforced rust the rust expansion occur simultaneously, the steel corrosion rate from 0% to 30% of the process, vaulted settlement of a total increase of 1.4%. 4, the corrosion rate varies between 1% -30%, considering only only consider the corrosion of reinforcement steel corrosion regardless of corroded expansion lining concrete internal forces did not change significantly, indicating Lining Internal Force large; consider corroded expansion force, lining the internal forces has been significantly increased, especially the the lining tensile stress increased significantly, and generated a lot of rust expansion cracks. Reinforcement rust expansion brought about the destruction of the lining structure is huge.
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