Grant-in-Aid for Scientific Research (A)
|Allocation Type||Single-year Grants|
|Research Institution||Saitama University|
MACHIDA Atsuhiko Saitama Univ., Civil Eng., Professor, 工学部, 教授 (50008869)
SEKI Hirosi Waseda Univ., Civil Eng., Professor, 理工学部, 教授 (40120919)
TSUJI Yukikazu Gunma Univ., Civil Eng., Professor, 工学部, 教授 (50048922)
OTSUKI Nobuaki Grad.Sch.of Tokyo Inst.Tech., Civil Eng., Prof., 大学院・理工学研究科, 教授 (40211106)
UEDA Tamon Hokkaido Univ., Grad.Sch.Civil Eng., Prof., 大学院・工学研究科, 教授 (00151796)
NIWA Jun-ichiro Grad.Sch.of Tokyo Inst.Tech., Civil Eng., Prof., 大学院・理工学研究科, 教授 (60164638)
睦好 宏史 埼玉大学, 工学部, 教授 (60134334)
|Project Period (FY)
2002 – 2004
Completed(Fiscal Year 2004)
|Budget Amount *help
¥55,120,000 (Direct Cost : ¥42,400,000、Indirect Cost : ¥12,720,000)
Fiscal Year 2004 : ¥11,700,000 (Direct Cost : ¥9,000,000、Indirect Cost : ¥2,700,000)
Fiscal Year 2003 : ¥13,910,000 (Direct Cost : ¥10,700,000、Indirect Cost : ¥3,210,000)
Fiscal Year 2002 : ¥29,510,000 (Direct Cost : ¥22,700,000、Indirect Cost : ¥6,810,000)
|Keywords||Management and control system / Diffusion coefficient / Electro-migration method / Deterioration due to chloride ion / Carbonation / Alkali-aggregate reaction / Deterioration due to combined effects / Acoustic emission method / 維持・管理 / 補修・補強 / モニタリング / 劣化 / 塩化物イオン / AE / 非破壊試験|
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
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