基于分片响应面的钢筋混凝土梁变形随机模拟

STOCHASTIC SIMULATION OF REINFORCED CONCRETE BEAMS WITH A PIECEWISE RESPONSE SURFACE

将响应面与蒙特卡洛方法结合,可降低随机模拟的计算代价。但当钢筋混凝土梁所受荷载接近开裂荷载时,梁体的变形响应面形状将出现不光滑的现象。采用传统的单一响应面方法来描述结构响应将与实际产生明显的偏差。采用改进的分片响应面技术结合蒙特卡洛方法,建立了钢筋混凝土梁变形随机分析模型。以钢筋混凝土试验梁作为算例,讨论了分片参数的合理取值,并验证了方法的正确性。

Significant computational cost can be saved by using a hybrid method combining Monte Carlo(MC) method with a response surface in stochastic simulation. However, when the applied load is close to the cracking load, it can be found that the real deflection response of a reinforced concrete(RC) beam may not be smooth. In this case, the traditional response surface method, which covers the all responses with a single function, may induce significant error. To avoid this problem, a piecewise response surface is adopted in an MC simulation model for RC beams. The deflection variability RC beam tests is evaluated using the presented model. The parameters of piecewise response surface are discussed. The results demonstrate the usefulness of the present model in computing the stochastic nonlinear deflection of cracking RC beam.