| A large number of concrete materials consumption led to a shortage of natural sand and gravel resources, and industrial pollution caused acid rain brings a significant decline in the durability of concrete structures. In view of the above problems, this dissertation mainly uses the waste ceramic tile as the recycled coarse aggregate, waste ceramic tile powder as admixture, preparation the new green recycled concrete.According to the characteristics of acid rain in Hunan Province, the indoor simulated acid rain solution of dry wet cycling experiment, study of acid rain erosion effect of recycled concrete carbonation depth and will and outdoor exposure compared to a year data. Through the test analysis under different erosion conditions of concrete appearance erosion, mass variation rate, compressive strength, relative dynamic elastic modulus and neutral depth index, of recycled aggregate on concrete acid rain erosion resistance ability, and from the micro perspective analysis of the corrosion mechanism. Research results indicate that:In outdoor exposure test, compared with the original stone concrete, not mixed with waste tile powder doped synthetic material of the waste ceramic tile recycled aggregate concrete mass variation rate loss is slightly larger, but the compressive strength is higher. Furthermore, mixed with waste ceramic powder of the waste ceramic tile of recycled concrete, the mass variation rate is high, the compressive strength is low.In simulated acid rain solution erosion conditions, compared with the original stone concrete, not mixed waste tile powder doped synthetic material of the waste ceramic tile recycled coarse aggregate concrete of higher compressive strength, mass variation rate is low, the by acid rain erosion depth of neutral minimal, which indicates that the waste ceramic tile recycled coarse aggregate concrete anti erosion ability better than native gravel concrete; However, the incorporation of waste ceramic powder of compressive strength of recycled aggregate concrete decreases with the increase of waste ceramic powder content, the neutral depth increases with the increase of waste porcelain powder content, it is recommended waste ceramic powder content should becontrolled within 20%. The neutral depth of recycled concrete with waste ceramic tile increases with the decrease of p H value. In the early stage of erosion, the p H value was less affected by the acid rain erosion degree of concrete, but in the later stage of erosion, with the p H value decreased, the concrete was intensified by acid rain.Compared with the standard curing condition, in simulated acid rain erosion regeneration concrete chemical combination with low water content and waste tiles of recycled concrete chemical combined water content and decreased with the increase of waste ceramic powder content. In the same acid rain erosion conditions, reduce the alkalinity of the concrete surface, the hydration products of decomposition layer caused by shedding; with the degree of erosion depth, concrete internally generated a lot of gypsum crystal, resulting in volume expansion caused cracking. Compared with the primary crushed stone concrete, the chemical binding water content of recycled concrete is lower, and the internal microstructure is more compact. |
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