清水磚牆貼附鋼絲網補強在水平加載下之分析計算及實驗比較

Calculation and Experimental Comparison for Masonry Wall Strengthened with Wire Mesh under Horizontal In-Plane Loading

清水磚牆內側貼附鋼絲網之補強工法，係藉由粉刷層與鋼絲網構成補強層，以改善牆體之水平耐剪能力。此工法具有造價便宜與保存既有空間景觀之優點，常為保存者所採用。為建立此工法在耐震評估或補強過程所需之加載- 位移關係及相關計算過程，本文假定補強提昇分別由鋼絲及包覆鋼絲網之水泥砂漿粉刷層共同提供。其中鋼絲網之貢獻係以剪力摩擦之觀念計算，並將鋼絲降伏對磚牆造成之額外正向力納入位移估算。經由5 道鋼絲網補強試體實驗結果與計算比較，顯示本文之計算方式大致可合理得到其水平極限抗剪力與對應之變位，而牆體之水平加載- 位移推估曲線亦與實驗曲線相近。在實務應用上，設計者經由此計算曲線，可預先對清水磚牆貼附鋼絲網補強工法之效益做明確掌握。

The masonry wall retrofitted with wire mesh in the inside surface has been commonly adopted in Taiwan for historic building , due to its advantages of economic and not changing the architectural scenery. For establishing the calculation process of the load-displacement relationship curve for the brick wall strengthened with wire mesh , in this paper , we assume the strengthening effect is contributed by wire mesh and the mortar that enclose wire mesh. The contribution of wire mesh is based on the concept of shear friction. The additional compressive stress of the brick wall due to the wire yield stress was also counted in the calculation of wall displacement. According to the comparison of calculation and five brick specimens, it shows that the ultimate loading and displacement of the brick wall under in-plane loading can be obtained reasonably. Besides the calculated load-displacement curves obtain an approximately good agreement with the test results. In practical usage, based on the calculated load-displacement curves, designer can clearly understand the effect and behavior for the brick wall strengthened with wire mesh.