Towards a sustainable design of regular and prestressed concrete structure

结构工程设计的进步受到现代社会在环境，可持续性以及材料和技术的有效利用方面的意识的强烈影响。工业的需要反映了社会对改善所有公民和后代生活质量的看法和要求。预应力混凝土，特别是预应力混凝土劣化的研究在满足建筑业未来的需求，迫切解决国家公路的恶化状况，提高其性能，耐久性和效率方面起着至关重要的作用。 虽然在评估普通钢筋的腐蚀方面已经取得了相当大的进展，但现有的电化学测试不能方便地检测预应力钢筋的劣化，需要根据现场预应力钢绞线的现有条件进行修改和校准。由于几个事实，例如，高应力和腐蚀的联合作用可能导致钢的突然失效和断裂;为普通钢筋混凝土开发的修复技术不能应用于预应力结构，因为完全预应力不允许混凝土拆除。 该研究计划的主要目标是增加现有和新建预应力混凝土结构耐久性的知识，以延长其使用寿命，最大限度地减少维修和监测成本，并提高其长期安全性。对预应力钢-混凝土界面粘结性能的全面研究是解决这一问题的关键。 此外，对各种设计、评估和干预方案的长期经济影响的理解开发了一套新的HPC配方，其中包含工业/市政副产品材料。这些配方将延长基础设施的使用寿命，最大限度地减少社会成本，减少交通拥堵/生产力损失，并改善人类/环境健康。提供将生命周期分析纳入主要设计和施工决策的政策建议。开发专门针对预应力混凝土的退化模型。

The progress in structural engineering design is strongly influenced by the awareness of our modern society in the areas of the environment, sustainability and the efficient use of materials and technology. The need of industry is a reflection of the perception of the society and its demand on improving the quality of life for all citizens and the future generations. Prestress concrete and in particular research on deterioration of prestressed concrete plays a vital role in fulfilling future needs of the construction industry, to urgently address the deteriorating conditions of the nation's highways, and to improve their performance, durability and efficiency.  While considerable progress has been made in evaluating corrosion of normal reinforcing steel, the prestressing steel deterioration cannot be detected conveniently with the available electrochemical tests, which, needs to be modified and calibrated to the existing condition of prestressing strands in the field. Due to several facts, for example, the combined action of high stress and corrosion can lead to a sudden failure and rupture of the steel; and repair techniques developed for normal reinforced concrete can not be applied to prestressed structures because full prestressing does not allow concrete removal.  The main objectives of this research program is to increase the knowledge on the durability of existing and newly built prestressed concrete structures in order to prolong their service life, minimize repair and monitoring costs and to improve their long-term safety. Comprehensive study on the bond at the prestressing steel-concrete interface would be vital to address the deterioration problem.  Also the understanding of the long term economic effects of various design, assessment and intervention options Develop a new set of HPC formulations that incorporate industrial/municipal by-products materials. These formulations will extend infrastructure service life, minimize social costs, reduce traffic congestion/productivity losses, and improve human/environmental health. Provide policy recommendations that incorporate life cycle analysis into major design and construction decisions. Develop degradation models specifically for prestressed concrete.