检索结果-南通市图书馆

New few parameters differential evolution algorithm with application to structural identification

Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 1-14页

作者： rita greco Ivo Vanzi Department of Civil Engineering Environmental Territory Building and Chemical Polytechnic University of Bari Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio"

Differential evolution algorithm(DEA) is a stochastic, population-based global optimization method. In this paper, we propose new schemes for both mutation and crossover operators in order to enhance the performances of the standard DEA. The advantage of these proposed operators is that they are "parameters-less", without a tuning phase of algorithm parameters that is often a disadvantage of DEA. Once the modified differential evolutions are presented, a large comparative analysis is performed with the aim to assess both correctness and efficiency of the proposed operators. Advantages of proposed DEA are used in an important task of modern structural engineering that is mechanical identification under external dynamic loads. This is because of the importance of using a "parametersless" algorithm in identification problems whose characteristics typically vary strongly case by case, needing of a continuous set up of the algorithm proposed. This important advantage of proposed optimizers, in front of other identification algorithms, is used to develop a computer code suitable for the automatic identification of a simple supported beam subject to an impact load, that has been tested both using numerical simulations and real standard tests dynamic. The results point out that this algorithm is an interesting candidate for standard applications in structural identification problems.

关键词： Differential evolution Parametric identification Structural identification Optimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

To compute or not to compute?

引用

Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 85-93页

作者： Alessandra Fiore Ivo Vanzi Camillo Nuti Cristoforo Demartino rita greco Bruno Briseghella Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio" DICAR Department of Civil Engineering and Architecture Polytechnic University of Bari College of Civil Engineering Fuzhou University Department of Architecture Roma Tre University College of Civil Engineering Nanjing Tech University DICATECH Department of Civil Engineering Environment Territory Building and Chemical Polytechnic University of Bari

In a previous paper "to retrofit or not to retrofit?"(Nuti and Vanzi, 2003) a straightforward procedure able to forecast the economic return of seismic structural upgrading was presented. More recently, the authors realized that the final mathematical results can be much simplified so as to allow back-of-an-envelope computation. The title of this paper tries to highlight precisely this aspect, namely that for many a regular seismic structural upgrading cases, nearly no computation is needed(apart from one subtraction and one multiplication) to assess their economic convenience. These findings are presented and discussed in this paper, together with a state of the art on the cost-studies available in literature and technical codes. The mathematical formulation leading to the proposed approximation is suitably explained, underlining its applicability field and comparing it with the rigorous solution. Also a table and a formula are furnished that alternatively allows to calculate the maximum estimation errors, in order to obtain an upper and lower bound for the maximum amount of money which should be allocated for seismic structural upgrading.

关键词： Seismic retrofitting Structural reliability Safety Optimization Cost minimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Probabilistic seismic response and uncertainty analysis of continuous bridges under near-fault ground motions

引用

Frontiers of Structural and Civil Engineering 2019年第6期13卷 1510-1519页

作者： Hai-Bin MA Wei-Dong ZHUO Davide LAVORATO Camillo NUTI Gabriele FIORENTINO Giuseppe Carlo MARANO rita greco Bruno BRISEGHELLA College of Civil Engineering Fuzhou UniversityFuzhou 350108China Department of Architecture Roma Tre UniversityRoma 00154Italy College of Civil Engineering and Architecture Politecnico di Bari UniversityBari 70126Italy

Performance-based seismic design can generate predictable structure damage result with given seismic ***,there are multiple sources of uncertainties in the seismic design process that can affect desired performance *** paper mainly focuses on the effects of near-fault pulse-like ground motions and the uncertainties in bridge modeling on the seismic demands of regular continuous highway *** modeling a regular continuous bridge with OpenSees software,a series of nonlinear dynamic time-history analysis of the bridge at three different site conditions under near-fault pulse-like ground motions are carried *** relationships between different Intensity Measure(IM)parameters and the Engineering Demand Parameter(EDP)are *** selecting the peak ground acceleration as the most correlated IM parameter and the drift ratio of the bridge column as the EDP parameter,a probabilistic seismic demand model is developed for near-fault earthquake ground motions for 3 different site *** this basis,the uncertainty analysis is conducted with the key sources of uncertainty during the finite element *** the results are quantified by the"swing"base on the specific distribution range of each uncertainty parameter both in near-fault and far-fault *** the ground motions are selected from PEER database,while the bridge case study is a typical regular highway bridge designed in accordance with the Chinese Guidelines for Seismic Design of Highway *** results show that PGA is a proper IM parameter for setting up a linear probabilistic seismic demand model;damping ratio,pier diameter and concrete strength are the main uncertainty parameters during bridge modeling,which should be considered both in near-fault and far-fault ground motion cases.

关键词： continuous bridge probabilistic seismic demand model Intensity Measure near-fault uncertainty

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Volume/thrust optimal shape criteria for arches under static vertical loads

引用

Journal of Traffic and Transportation Engineering(English Edition) 2018年第6期5卷 503-509页

作者： Giuseppe Carlo Marano Francesco Trentadue rita greco Ivo Vanzi Bruno Briseghella DICAR Department of Civil Engineering and ArchitectureTechnical University of BariBail 70125Italy College of Civil Engineering Fuzhou UniversityFuzhou 350108China DICATECH Department of Civil EngineeringEnvironmentTerritoryBuilding and ChemicalTechnical University of BariBari 70125Italy Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio"Pescara65127Italy

Arches are widely used when large spans are necessary, e.g. to overpass large rivers, and further possess unquestioned aesthetics advantages. Their structural efficiency depends primarily on optimal material exploitation, i.e. minimization of internal stress eccentricity,and on minimization of structural material volume. An efficient structure, under these terms, further requires simpler and lighter scaffolding, contributing in minimizing construction *** arches have millenary use and many researches dealing with this typology are available in literature, there is still scope for design optimization. The proposed study is framed within this context. Investigation is limited to statically determinate plane arches under vertical load. The problem of finding the profile of an equal strength catenary subjected to its self-weight is spread out to the case of an inverted catenary of equal strength under its self-weight and an external constant load. In the first optimization step, constant normal stress is imposed at all sections, to maximize material exploitation, and the resulting arch centerline shape is computed in closed form. In the second step, the ensemble of foundations and arch is considered and optimized, taking the linear combination of arch weight and thrust as objective function. The linear combination is dependent on a single variable, and minima of the objective function(i.e. optimal geometric shape parameters) are computed and charted to be simply used in the design process.

关键词： Plane arch Vertical loads Optimal shape Volume/thrust objective functions Analytical solution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：