1、CORROSION AND PRESTRESSED CONCRETE BRIDGESAdrian T. Ciolko, P.E.1腐蚀和预应力混凝土桥梁阿德里安·T.CiolkoP.E.1AbstractThe impact on bridge reliability, of prestressing steel deterioration and tendonrupture created by corrosion mechanisms, is much more critical and rapid thanthat of any othe
2、r component of a prestressed concrete bridge.Additionally,deterioration of embedded prestressing reinforcement in these structures may notnecessarily be made visible through manifestation of external distress in theConcrete.摘要腐蚀机制引起预应力钢筋的恶化和断裂,进而对桥梁的可靠性产生影响,这比对预应力混凝土桥的其他部分的影
3、响更加严重,也更加迅速。此外,在这些结构中,有粘结预应力钢筋的恶化也不必要通过混凝土外部糟糕的状况表现出来。Initiating mechanisms and particular forms of corrosion affectingprestressed concrete structures are described based on the author’s experience.These degradation mechanisms include:•Chlorides and Corrosion•Concrete Carbon
4、ation Effects•Influence of Concrete Cracking•Electrochemical (Macrocell) and Pitting Corrosion•Stress Corrosion Cracking and Steel Embrittlement•Fretting Corrosion•Corrosion and Fatigue关于腐蚀影响预应力混凝土结构的最初机制和特定形式的描述是基于作者的经验。这些退化机制包括:•氯化物和腐蚀•混凝土碳化影响•混凝土裂缝的影响•电化学(小区)和孔蚀•应力腐蚀开裂和钢的
5、脆断•微动腐蚀•腐蚀和疲劳Recently, prestressed, post-tensioned concrete structures have beenthought to be threatened by certain premature performance impairmentsworldwide, predominately when defects were present.These problems maycontinue to manifest themselves. Therefore, corrosion pre
6、ventative methods andneed for scrutiny during construction and maintenance needs will be described.For existing structures experiencing evidence of premature distress, the authordiscusses case-study based investigative techniques and available rehabilitationStrategies.最近,世界各
7、地的预应力、后张法预应力混凝土结构已经被认为受到某些早期性能破坏的威胁,尤其是已经存在的缺陷。这些问题可能继续危害结构。因此,我将对预防腐蚀的方法和施工与维护期间的检测进行介绍。对于遭受早期破坏的现有结构,作者讨论案例研究是基于探测技术和有效的修复手段。1 Vice President, Construction Technology Laboratories, Inc., 5400 Old Orchard Road, Skokie,IL 60077.1Copyright ASCE 2005Structures 2005Structures
8、Congress 2005IntroductionThe first prestressed concrete bridge in the US wa