生态性生物磷酸盐胶凝材料及其在土木工程中的应用基础研究

Research of cementitious materials is an old and developing subject. The new kind of microbial cementitious materials with better stability of cement products and less environmental pollution are studied in this project with the consideration of release of ammonia and the instability of cement products for carbonate cementitious materials formed by microbial mineralization and eco-friendly of traditionaly cementitious materials in some fields. The main contents include: the microbe, which is able to take place mineralization and no harmful by-producets formation, is screened and domesticated. The composition, mix proportion and preparation process of Phosphate cementitious materials produced by microbe are researched. The biology, chemical mechanism and properties of mineralization products are studied. Meanwhile, the cementation mechanism is also researched. Moreover, the application effect, characterization methods and compatibility with plants, biological of phosphate cementitous materials produced by microbe in foundation consolidation, antiliquefaction and repair defects are investigated. On research, we aim at obtaining the mix proportion and preparation process, revealing the cementation mechanism and application methods, cultivating five to six graduates, applying for 5 invention patents and publishing 20 papers of SCI and EI articles.

胶凝材料的研发是一个古老却又不断发展的课题。针对目前国内外微生物矿化作用形成的碳酸盐胶凝材料存在释放氨气，胶结产物酸不稳定及传统胶凝材料在一些场合的生态友好性等问题，本课题旨在研究一种无环境污染，胶结产物更加稳定的新型微生物胶凝材料。主要研究内容包括：无有害副产物形成且能矿化形成磷酸盐的微生物分离、筛选和驯化；基于生物矿化的磷酸盐胶凝材料组成、配方及制备工艺；微生物磷酸盐胶凝材料矿化产物形成的生物、化学机制及性质；微生物磷酸盐胶凝材料的胶结机理及其在加固地基、抗液化以及修复建筑材料缺陷等领域的应用效果、表征方法及与植物、生物的相容性。通过研究，确定生物磷酸盐胶凝材料配方、制备工艺，揭示其胶结机理并探明其应用方法。培养研究生5-6名，发表SCI和EI收录论文20篇，申请发明专利5件以上。

微生物水泥是基于微生物诱导矿化形成无机矿物从而固结松散颗粒的一类新型胶凝材料，在地基加固、扬尘治理，重金属离子固化等领域具有应用前景。本论文通过筛选、培育出一种适合胶结用的磷酸盐矿化菌，对特定底物作用并矿化沉积出生物磷酸盐矿物，从而起胶结作用。通过添加可溶性磷酸盐至生物碳酸盐水泥中，将胶结过程中产生的氨根转化为环境友好物质鸟粪石，与碳酸盐一起胶结松散粒子。围绕生物磷酸盐水泥和复合水泥的研制，探究了磷酸盐矿化菌水解底物生成磷酸根的类型，明确了生物磷酸盐的特性；提出采用预沉淀拌合工艺，以生物磷酸钡盐为例研究了预沉淀拌合工艺的参数和生物磷酸盐水泥基本配方；针对生物碳酸钙水泥中氨气释放问题，提出采用磷酸盐将其转化为鸟粪石制备复合生物水泥的技术路线，并深入研究了复合水泥的配方。使用磷酸盐矿化菌将游离态重金属钝化为稳定的、颗粒较大的矿化产物，避免土壤中的重金属向食物链迁移。通过对菌种生长特性及酶活性的研究，为钝化剂用量提供理论依据，并根据实际应用条件确定具体的配方用量。结合研究，发表SCI和EI收录论文33篇，授权发明专利10件以上，至少培养博士、硕士研究生6名。