The aim of the research was to determine reliability function of net cross-section resistance in relation to accidental eccentricity of nominally centric holes. The response surface method was used by taking into account the relevant Eurocode design provisions and reliability requirements. Within the response surface method, the central composite design method and the least square method were used with the employment of Monte Carlo simulations. The probable distributed variables such as strength f _y, breadth b, thickness t, diameter d ₀ and eccentricity e were determined by the central composite design method. 280 different numerical simulations were set up with varying variables. A log-normal distribution for strength (f _y) and a normal distribution for geometrical variables (b, t, d ₀,e) were employed by taking into account the coefficients of variations: V _fy=0.07, V _b,=0.005, V _l=0.05 and V _d0=0.005. In order to determine the influence of eccentricity on partial safety factor, several normal distributions with different variation factors were applied in the analysis. The influence of the edge distance of the hole e ₂ over d ₀ ratio on the partial safety factor was determined by varying mean values of variable b. For comparison, two types of steel were used: structural steel S235 and high strength steel S690. Numerical simulations of the net cross-section resistance F _u were performed with ABAQUS 6.7. The response surface for the net cross-section resistance was determined by introducing a quadratic approximation function and by applying the least square method. The partial safely factor was then (statistically) obtained by means of robust Monte Carlo simulations on the calculated response surface.

中文翻译：

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带有孔意外偏心的净截面电阻的可靠性分析

该研究的目的是确定与名义中心孔的意外偏心有关的净横截面阻力的可靠性函数。考虑到相关的欧洲规范设计规定和可靠性要求，使用了响应面法。在响应面法内，采用了中心组合设计法和最小二乘法，并采用了蒙特卡洛模拟法。可能的分布变量，例如强度f _y，宽度b，厚度t，直径d ₀和偏心率e由中央复合设计方法确定。设置了280个具有不同变量的不同数值模拟。考虑到变化系数V _fy = 0.07，V _b，= 0.005，采用强度的对数正态分布（f _y）和几何变量的正态分布（b，t，d ₀，e）。V _l = 0.05和V _d0 = 0.005。为了确定偏心距对部分安全系数的影响，在分析中应用了几种具有不同变化系数的正态分布。通过更改变量b的平均值，确定孔e ₂的边缘距离超过d ₀比率对部分安全系数的影响。为了进行比较，使用了两种类型的钢：结构钢S235和高强度钢S690。净截面电阻F _u的数值模拟 使用ABAQUS 6.7进行。通过引入二次逼近函数并应用最小二乘法确定净截面电阻的响应面。然后（通过统计方法）在计算出的响应面上通过鲁棒的蒙特卡洛模拟获得部分安全系数。