摘要
拱坝在长期服役过程中受材料老化、环境侵蚀等因素影响,其动弹性模量真实值与设计值存在一定差异,合理确定运行期高拱坝及其地基的原型动弹性模量参数对于监控拱坝的振动安全至关重要。由于模态参数更能从整体上反映结构的振动特性,基于拱坝原型振动模态参数反演拱坝及地基的动弹性模量在理论上更为精确,为此,本文提出了一种基于敏感性分析与粒子群算法的拱坝原型动弹性模量反演方法。首先,建立了反映拱坝及地基各分区动弹性模量与拱坝模态参数之间非线性映射关系的响应面数学模型,基于正交试验法分析了拱坝及地基的动弹性模量区域对拱坝模态参数的敏感性,并以此确定了待反演的动弹性模量区域。其次,提出了基于响应面数学模型计算模态参数和原型振动模态参数的拱坝及地基分区动弹性模量反演最优化数学模型,将动弹性模量参数反演问题转化为目标函数最优化求解问题。最后,采用自适应惯性权重的粒子群优化算法对目标函数进行寻优求解,反演出各分区实际动弹性模量。通过原型工程实例分析表明,该方法合理可行且具有很好的精度,为反演拱坝的动弹性模量提供了一条新思路。
Due to various external factors such as material aging and environmental erosion during the long service of the arch dam,the actual values of dynamic elastic modulus(DEM)are usually different with the design.The prototype DEM of a high arch dam and its foundation during operation are critical to the safety monitoring of the arch dam.Since the modal parameters can better reflect the vibration characteris⁃tics of the structure,it is more accurate in theory to invert the DEM of the arch dam and foundation based on the prototype vibration modal parameters of arch dam.Therefore,an inversion method is proposed for prototype DEM of arch dam based on sensitivity analysis and particle swarm optimization.First,the re⁃sponse surface mathematical model reflecting the nonlinear mapping relationship between the DEM of arch dam and its foundation and the modal parameters of arch dam is established.The sensitivity of the DEMs to the modal parameters of arch dam is analyzed by the orthogonal test method,and the DEMs to be in⁃verted are determined.Second,the optimal mathematical model for the inversion of the DEM of arch dam and its foundation is proposed based on the calculated modal parameters of the response surface mathemati⁃cal model and prototype vibration modal parameters,and the inversion of the DEMs is transformed into an objective function optimization problem.Finally,a particle swarm optimization algorithm with adaptive weights is used to optimize the objective function,and the real DEMs are inversed.Prototype engineering analysis shows that the method has satisfactory feasibility and precision and provides a novel idea for the in⁃version of the DEM of an arch dam.
作者
李火坤
王刚
魏博文
黄伟
陈良捷
LI Huokun;WANG Gang;WEI Bowen;HUANG Wei;CHEN Liangjie(School of Civil Engineering and Architecture,Nanchang University,Nanchang 330031,China)
出处
《水利学报》
EI
CSCD
北大核心
2020年第11期1401-1411,共11页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(51879126,52079061,51779115,51909115)
江西省杰出青年基金项目(2018ACB21018)。
