偏心載重作用於銲道之強度分析

Strength Analysis of Welded Connections under Eccentrical Loads

張哲綸(Zhe-Lun Zhang)

指導教授 ： 徐暐亭

朝陽科技大學/理工學院/營建工程系/碩士(2016年)

摘要

銲接接合的力學行為複雜，根據銲道的幾何形狀、強度、偏心載重等因素做為設計上的考量。本研究指在研究鋼結構銲道受偏心載重分析，並比較六種分析方法。銲接接合主要分析方法為彈性分析與極限分析兩種，而其中極限分析為瞬時旋轉中心法，需要考慮最大的變形偏心載重作用於銲道而未通過銲道斷面的形心時，銲道斷面將根據一個點產生偏移與旋轉，此點為瞬時旋轉中心點(IC)，此方法需以試誤法求出，計算過程繁雜、一般人員在外大多數的銲接形式是無法用計算機求出。而相較於彈性分析，彈性分析計算簡單，但是計算結果過於保。分析方法有彈性分法、極限瞬時旋轉中心法、AISC設計手冊查表法、Iwankiw之近似公式、修正Iwankiw近似公式和分段Iwankiw修正法。極限瞬時旋轉中心法是為最準確的。Iwankiw之近似公式、修正Iwankiw近似公式和分段Iwankiw修正法計算過程比極限瞬時旋轉中心法更容易。最常用為彈性分析計算過程是最簡單和保守，但是誤差最大。AISC設計手冊提供作用角度有限制六個特定值(0°、15°、30°、45°、60°、75°)，都是根據瞬時旋轉中心法方法，對於非特定作用角度下的強度以查表內插法來求推導出的C值，可以發現在多數的銲接形式下其值會高估，這並不是完全合理的。與其他方法相比，修正Iwankiw的方法和分段Iwankiw的方法更接近瞬時旋轉中心法，且合理。本研究以便利性與準確性上的考量，建議使用修正Iwankiw近似公式以及分段Iwankiw修正法基於各種情況下，工程師可以選擇其方法做為設計上的參考。

關鍵字

填角銲 ； 偏心載重 ； 彈性分析 ； 瞬時旋轉中心法 ； 近似公式

並列摘要

The welded joints Mechanical behavior is complex, according to weld groups geometry, strength, eccentrically loaded and other factors as design considerations. This research conducted to study weld groups of steel construction the eccentrically load. Furthermore, apply the six analytical methods compared. Fillet weld analysis, there are two main methods, one is elastic method, it is an easy task to use, based on the eccentric force can be moved the center of gravity of the weld group, is resolved into a force acting though the center of gravity of the weld group and a moment. The other is ultimate design, it is complex calculations to analysis, based on the IC location depends upon the geometry of the weld group and the location and direction of the loading. Theoretically, the force equilibrium equations should be satisfied at the correct IC. Method of analysis had elastic method, instantaneous center of rotation method (IC method), AISC design tables method, Iwankiw’s method, correction Iwankiw’s method and piecewise Iwankiw’s method respectively. The IC method is the most accurate. Calculation process of the Iwankiw’s method, correction Iwankiw’s method and piecewise Iwankiw’s method are more easily than IC method. However, the most commonly used elastic method is the calculation for the most simple and conservative, but the error is the largest. AISC manuals provide the C coefficients for six specific load inclination angles only, which were derived based on the IC method. For a non-tabulated value have the tendency to linearly interpolate the C coefficient for a nonspecific angle value. However, this is not totally justifiable. Compared with other methods, correction Iwankiw’s method and piecewise Iwankiw’s method are closer IC method Based on case, engineers can be selection methods used as a reference design.

並列關鍵字

Fillet Weld ； Eccentric Load ； Elastic Method ； Instantaneous Center of Rotation Method ； Approximate Method

參考文獻

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