Prediction for Nonlinear Lateral Load-Deflection Curves of RC Frames

• Main Authors: HSU YU-CHE, 許毓哲
• Other Authors: SHEU MAU-SHONG
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/79337133239733414064

碩士 === 國立成功大學 === 建築學系 === 88 === ABSTRACT The performance-based design of building structure must check the story drift ratio under different recurrence earthquakes. If we want to get the nonlinear story drift ratio under the different porbability of exceedance, we must use the nonlinear analysis program. But the nonlinear analysis program is not popular at current stage. If we have a simple method to get the nonlinear lateral load-deflection curve compendiously, it is convient for the structural designers to estimate the member size of the structure at the plan stage of performance-based design. The purpose of this paper is try to get nonlinear lateral load-deflection curve by using the linear analysis program(such as ETABS), cooperate with the concept of elastic-plastic bilinear lateral load-deflection curve of BUILDING SEISMIC DESIGN CODE. We can correct the elastic-plastic bilinear lateral load-deflection curve of BUILDING SEISMIC DESIGN CODE to the curve which is close to actual nonlinear lateral load-deflection curve of building structure. This paper analyses the X and Y dircetion of the fifteen RC frame structures with different stories, different plans and different use. The conclusions are as follow: 1. The ultimate lateral strength of frame structure : This paper considers the effect of and （n）.The average error of ultimate lateral strength magnificent factor is 4.61% in 5F group, 6.79% in 10F group and 2.12% in 20F group. In general, the average error is acceptable. 1. The initial lateral stiffness of frame structure：The minimun error is 0.37%, the maximun error is 37.5% and the average error is 8.42% for predicted initial stiffness. In general, the average error is acceptable. But for some cases the error is too large. The reason is not only beams crack but also columns crack under dead load and live load. But this paper does not consider the effect of columns，s crack when predictes frame initial lateral stiffness . 3. Predicted result of nonlinear V─Δcurve : The predicted V─Δ curve is very close to the result of nonlinear spectrum method, especially at the curve of low base-shear. If we can，t get the actual ultimate lateral strength, the error is larger at the curve of high base-shear. 1. Check of performance-based design : According to the existing BUILDING CODE, the Fu of all the buildings under 475 year recurrence earthquake is 2.5. But the average Fu under 475 year recurrence earthquake calculated in this paper is 1.897, lower than the BUILDING CODE. And all the case，s Fu is lower than 2.5, the minimun Fu is 1.782. Keywords: RC frame structure, frame ultimate lateral strength, frame initial lateral stiffness, performance-based design, reduction factor of earthquake load