新型电石泥渣壳层陶粒制备及其对混凝土增强机制研究

Acetylene is an important chemical material, which is used mainly to make polyvinyl chloride, polyvinyl alcohol and vinylon. However, calcium carbide residue (CCR) generated by calcium carbide acetylene method cause great pollution to environment, comprehensive utilization of CCR is urgent. New-type silicate shell-aggregate will be prepared by the hydrothermal synthesis of CCR and silica materials（fly ash, tails of quartz sand used to pruduce high purity ferrosilicon）under the condition of 180℃saturated steam, the highest content of the CCR contained in silicate shell-aggregate can reach 50-80%. Shell thickness, shell constituents and shell structure design influencing aggregate physical performance and mechanical performance will be investigated. Mechanical performance and durable performance(frost resistance, impermeability and drying shrinkage ) of concrete with silicate shell-aggregate as coarse aggregate will be indepth explored, design criteria of shell-aggregate concrete will also be discussed,and then the key scientific problems of applying new-type shell aggregate into bearing structure will be discovered. Interface problem between silicate shell-aggregate and mortar and their collaborative enhancement mechanism will be studied by experiment. Mechanism that shell strengthen aggregate and its concrete will be studied by macro-scale calculation and mesoscopic-scale simulation, and then the constitutive relation of gradient shell-aggregate concrete will be established. Obtained results not only can provide theoretical basis for use of shell-aggregate in structural concrete,but also can open up new research perspective for resource utilization of other solid waste.

电石-乙炔法生产聚氯乙烯、聚乙烯醇、维纶等产生的电石泥渣数量巨大，导致环境污染严重，其综合治理和资源化利用的研究意义重大。本项目以宁夏地区工业生产中产生的电石泥渣、粉煤灰及石英尾砂为原料，开展水热合成法制备高性能壳层硅酸盐陶粒研究，获得电石泥渣掺加量达50%-80%的陶粒。对影响陶粒物理性能及力学性能的壳层厚度、壳层组成及壳层结构设计等主要因素进行研究，深入探讨这种承重结构用新型陶粒混凝土的力学性能和耐久性能（抗冻性、抗渗性和干燥收缩性能），探明其在承重结构中应用的关键科学问题。采用实验研究壳层硅酸盐陶粒和砂浆基体间的界面问题和协同增强机制，采用实验、宏细观力学分析和数值模拟相结合的方法，对壳层增强陶粒及其混凝土物理性能和力学行为进行阐述和机理探讨，建立梯度壳层陶粒混凝土的本构关系，为壳层陶粒用于结构混凝土提供理论依据，为其它固体废弃物的资源化利用开辟新的研究视角。

电石-乙炔法生产聚氯乙烯、聚乙烯醇、维纶等产生的电石泥渣数量巨大，导致环境污染严重，其综合治理和资源化利用的研究意义重大。本项目以宁夏地区工业生产中产生的电石泥渣、粉煤灰及石英尾砂为原料，开展水热合成法制备高性能壳层硅酸盐陶粒研究，获得了电石泥渣掺加量达50%-80%的陶粒。对影响陶粒物理性能及力学性能的壳层厚度、壳层组成及壳层结构设计等主要因素进行了研究，深入探讨了这种承重结构用新型陶粒混凝土的力学性能和耐久性能（抗冻性、抗渗性和干燥收缩性能），探明其在承重结构中应用的关键科学问题。采用实验研究了壳层硅酸盐陶粒和砂浆基体间的界面问题和协同增强机制，采用实验、宏细观力学分析和数值模拟相结合的方法，对壳层增强陶粒及其混凝土物理性能和力学行为进行了阐述和机理探讨，为壳层陶粒用于结构混凝土提供了理论依据，为其它固体废弃物的资源化利用开辟了新的研究视角。