Study on System for Maintenance and Control of Structures as Social Foundation

对构建结构维护与控制系统所需的基本技术进行了深入的研究，并试图开发一种先进的系统，将已有的成果与现有系统相结合。(1)明确了影响非稳态氯离子浓度分布的因素，量化了裂缝对氯离子扩散的影响。(2)提出了氯离子、碳酸化和钙离子浸出引起的劣化的估算方法，提出了宏观单元腐蚀劣化的监测方法和电沉积方法。(3)将残余拉应变作为冻融劣化的指标，建立了混凝土的力学模型，分析了混凝土结构性能的变化。引入这一指标。(4)研究了碱…的作用。定量地阐明了硅酸锂与氯离子联合作用对钢筋锈蚀的影响，提出了氯离子和碳化联合作用下钢筋锈蚀速度的解析预测方法。(6)证实了声发射方法可用于在役混凝土结构劣化的诊断检测，并在混凝土结构裂缝分布等光纤传感监测方法方面取得了一些成果。将刚体弹簧模型与桁架网络模型相结合，建立了处理混凝土劣化引起的内应变变化的桁架网络模型。(8)对FRP片材和钢套加固效果进行了试验研究，提出了分析评价加固效果的方法，可以说，在框架结构变化不大的情况下，维护控制系统得到了很大的改善。较少

Elemental technologies that are needed to constitute maintenance and control system for structures were intensively studied and it was tried to develop an advanced system, incorporating obtained results to the existing system. The results on elementary technologies are as follows.(1)The factors that have a great influence on the distribution of unsteady-state chloride ion concentrations were made clear, and the effects of cracks on the diffusion of chloride ions was quantified.(2)The estimation methods of deterioration due to chloride ions, carbonation and leaching of calcium ions were developed, and a monitoring method on deterioration due to macro-cell corrosion as well as an electrodeposition method was presented.(3)The residual tensile strain was presented as an index of deterioration due to freezing and thawing, and a mechanical model of concrete to analyze the change of structural performances was developed, introducing this index.(4)Several facts were found on the effect of alka … More li-silica reaction(ASR) on the load carrying capacity of structures.(5)The effect of ASR combined with chloride ion on the corrosion of re-bars was quantitatively made clear, and it was presented that the corrosion speed due to combined attack of chloride ion and carbonation can be analytically predicted.(6)It was confirmed that the acoustic emission method can be applied to the diagnostic check on deterioration of concrete structures in use, and several results were obtained on monitoring methods for crack distributions and so forth of concrete structures by sensing using optical fibers.(7)An analytical method, in which the rigid body spring model is combined with the truss network model was developed to treat changes of internal strain accompanied by movement of substances due to deterioration of concrete.(8)The strengthening effects of FRP sheet wrapping and steel jacketing were studied experimentally and the method was developed to evaluate the effects analytically.It can be said that the maintenance and control system was improved greatly introducing the above-mentioned academic results, even the framework did not change so much. Less