Summary: | 碩士 === 朝陽科技大學 === 營建工程系碩士班 === 93 === This research is concentrated on the structural strengths and behaviors of cold-formed steel wall frames with or without sheathing material under monotonic shear loading condition. Three different thicknesses of calcium silicate board were used to be the sheathing material for the wall frames. The ultimate strength, stiffness, energy absorption, ductility ratio, and stiffness degradation were studied for each test specimen. In addition, two types of strain gages, one way and three ways, mounted on the specimen were used to study the stress distribution of specimen during the test. The maximum and minimum principal stresses of test specimens were also obtained based on the readings of strain gages.
It was observed that the ultimate strength of the wall frame with calcium silicate board is much greater than the strength of the wall frames without sheathing material under the monotonic shear loading condition. And the ultimate strength of wall frame with calcium silicate board increases with increasing the thickness of board. It was also found that the sheathings of wall performed as an entire unit to against the shear force when the horizontal displacement of wall is small. However, when the movement was large and induced the deformation or rupture of the screws, the calcium silicate boards behalf like individual to resist to horizontal forces. In final, it is suggested that the design ductility of the cold-formed steel wall framing system similar to the wall configuration conducted in this study can be assumed to be 2.53.
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