| Summary: | 碩士 === 國立成功大學 === 建築學系碩博士班 === 97 === It’s most important part that how to maintain the original features on restoration in the process of conserving and protecting cultural assets, the value of monuments and historical buildings increase along with the years increase, but its structure safety situation just opposite, decrease with the years increase. How to adopt suitable reinforcement on walls related with structure safety tight is dispensable to monuments and cultural assets preservation on principle which doesn’t affects the features.
The basic estimated formula is expand according to the cracked path developed by scholar recently, The structure program SAP 2000 V9.03 is used for numerical study, the prediction of retrofit device is simulated by simplifying for pure tension diagonals, which neglect the contribution of compression diagonals, the emphatic conclusion to be as follows after carrying out the experiments：
1. Brick arch failure mode：Cracks are separated into shear and flexural cracks, the shear and flexural crack of un-reinforced brick arch occur in arch angle 63o respectively and at the bottom of 3rd brick walls on both sides of opening.
2. The error of ultimate load prediction of un-reinforced brick arch： brick arch will be simplified to portal frame are used to preliminary estimation, in-plane stiffness which only provides from vertical frame, the average error between -20~20%；Structure program are used to simulate brick arch with shell elements analyzed, the average error between -15%~10%.
3. The error of ultimate load prediction after retrofitting：the error of structure program and preliminary estimation are between respectively 35~80% and 25~40%, the reason of error results from the slight deformation between the fixed beam relation with brick arch and reaction force base.
4. The impact of ultimate load after retrofitting：the ultimate load from cyclically loaded tests decrease by 12%, monotonically loaded tests increase by 20%, although it doesn’t increase in cyclically loaded tests, it enhances ductility of overall walls and avoids non-repairable cracks occurred as the view of retrofitted effectiveness.
The results of in-plane loading test shows that the story drift angle of yield point is 3.8/1000, visible crack is 2.2/1000,it could succeed the function of warning point if adjusting the yield point before the drift angle 2.2/1000 with further improvement of low-yield steel afterward.
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