Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 586

会议视频 9

年份

2023 51

2022 56

2021 44

2020 46

2019 46

2018 38

2017 41

2016 25

2015 26

2014 27

2013 23

2012 29

2011 11

2010 20

2009 12

2008 19

2007 21

2006 8

2005 9

2004 12

展开︾

关键词

优化 18

多目标优化 9

优化设计 8

遗传算法 6

不确定性 4

稳健设计 4

动态规划 3

智能制造 3

能源 3

一阶分析法 2

五品联动 2

仿真优化 2

分布式优化 2

参数率定 2

可视化仿真 2

可靠性灵敏度 2

粒子群优化算法 2

非线性 2

1)幂模型 1

展开︾

检索范围：

排序：展示方式：

Compressive strength prediction and optimization design of sustainable concrete based on squirrel search

《结构与土木工程前沿（英文）》页码 1310-1325 doi: 10.1007/s11709-023-0997-3

摘要： Concrete is the most commonly used construction material. However, its production leads to high carbon dioxide (CO₂) emissions and energy consumption. Therefore, developing waste-substitutable concrete components is necessary. Improving the sustainability and greenness of concrete is the focus of this research. In this regard, 899 data points were collected from existing studies where cement, slag, fly ash, superplasticizer, coarse aggregate, and fine aggregate were considered potential influential factors. The complex relationship between influential factors and concrete compressive strength makes the prediction and estimation of compressive strength difficult. Instead of the traditional compressive strength test, this study combines five novel metaheuristic algorithms with extreme gradient boosting (XGB) to predict the compressive strength of green concrete based on fly ash and blast furnace slag. The intelligent prediction models were assessed using the root mean square error (RMSE), coefficient of determination (R²), mean absolute error (MAE), and variance accounted for (VAF). The results indicated that the squirrel search algorithm-extreme gradient boosting (SSA-XGB) yielded the best overall prediction performance with R² values of 0.9930 and 0.9576, VAF values of 99.30 and 95.79, MAE values of 0.52 and 2.50, RMSE of 1.34 and 3.31 for the training and testing sets, respectively. The remaining five prediction methods yield promising results. Therefore, the developed hybrid XGB model can be introduced as an accurate and fast technique for the performance prediction of green concrete. Finally, the developed SSA-XGB considered the effects of all the input factors on the compressive strength. The ability of the model to predict the performance of concrete with unknown proportions can play a significant role in accelerating the development and application of sustainable concrete and furthering a sustainable economy.

关键词： sustainable concrete fly ash slay extreme gradient boosting technique squirrel search algorithm parametric analysis

HTML PDF 收藏

Effect of variable heat capacities on performance of an irreversible Miller heat engine

Xingmei YE

《能源前沿（英文）》 2012年第6卷第3期页码 280-284 doi: 10.1007/s11708-012-0203-0

摘要： Based on the variable heat capacities of the working fluid, the irreversibility coming from the compression and expansion processes, and the heat leak losses through the cylinder wall, an irreversible cycle model of the Miller heat engine was established, from which expressions for the efficiency and work output of the cycle were derived. The performance characteristic curves of the Miller heat engine were generated through numerical calculation, from which the optimal regions of some main parameters such as the work output, efficiency and pressure ratio were determined. Moreover, the influence of the compression and expansion efficiencies, the variable heat capacities and the heat leak losses on the performance of the cycle was discussed in detail, and consequently, some significant results were obtained.

关键词： Miller cycle variable heat capacity irreversibility parametric optimization

HTML PDF 收藏

Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

《结构与土木工程前沿（英文）》 2012年第6卷第3期页码 267-280 doi: 10.1007/s11709-012-0170-x

摘要： In this study, the structural control strategy utilizing a passive tuned mass damper (TMD) system as a seismic damping device is outlined, highlighting the parametric optimization approach for displacement and acceleration control. The theory of stationary random processes and complex frequency response functions are explained and adopted. For the vibration control of an undamped structure, the optimal parameters of a TMD, such as the optimal tuning frequency and optimal damping ratio, to stationary Gaussian white noise acceleration are investigated by using a parametric optimization procedure. For damped structures, a numerical searching technique is used to obtain the optimal parameters of the TMD, and then the explicit formulae for these optimal parameters are derived through a sequence of curve-fitting schemes. Using these specified optimal parameters, several different controlled responses are examined, and then the displacement and acceleration based control effectiveness indices of the TMD are examined from the view point of RMS values. From the viewpoint of the RMS values of displacement and acceleration, the optimal TMDs adopted in this study shows clear performance improvements for the simplified model examined, and this means that the effective optimization of the TMD has a good potential as a customized target response-based structural strategy.

关键词： tuned mass damper parametric optimization passive control white noise earthquake excitation

HTML PDF 收藏

Parametric sensitivity analysis of cellular diaphragm wall

Xi CHEN, Wei XU

《结构与土木工程前沿（英文）》 2012年第6卷第4期页码 358-364 doi: 10.1007/s11709-012-0177-3

摘要： The deformation law of the cellular diaphragm wall in deep foundation pits was studied through numerical simulation. Based on the example of the dock wall in engineering, the full three-dimensional finite element model was used to simulate the excavation of the foundation pit. Interaction between the cellular diaphragm wall and the soil was also taken into account in the calculation. The results indicated that the maximum lateral displacement, which is the evaluation index of sensitivity analysis, appeared on the top of the interior longitudinal wall with an excavation depth of 10 m. The centrifuge model test was carried out to study the deformation regulation for a cellular diaphragm wall. The most sensitive factor was found by adjusting the length of the partition wall, the spacing of the partition wall and the thickness of the wall. In the end, a suggestion was proposed to optimize the cellular diaphragm by adjusting the length of the partition wall.

关键词： cellular diaphragm wall sensitivity analysis optimization centrifuge model test

HTML PDF 收藏

Concurrent optimization of structural topology and infill properties with a CBF-based level set method

Long JIANG, Yang GUO, Shikui CHEN, Peng WEI, Na LEI, Xianfeng David GU

《机械工程前沿（英文）》 2019年第14卷第2期页码 171-189 doi: 10.1007/s11465-019-0530-5

摘要： In this paper, a parametric level-set-based topology optimization framework is proposed to concurrently optimize the structural topology at the macroscale and the effective infill properties at the micro/meso scale. The concurrent optimization is achieved by a computational framework combining a new parametric level set approach with mathematical programming. Within the proposed framework, both the structural boundary evolution and the effective infill property optimization can be driven by mathematical programming, which is more advantageous compared with the conventional partial differential equation-driven level set approach. Moreover, the proposed approach will be more efficient in handling nonlinear problems with multiple constraints. Instead of using radial basis functions (RBF), in this paper, we propose to construct a new type of cardinal basis functions (CBF) for the level set function parameterization. The proposed CBF parameterization ensures an explicit impose of the lower and upper bounds of the design variables. This overcomes the intrinsic disadvantage of the conventional RBF-based parametric level set method, where the lower and upper bounds of the design variables oftentimes have to be set by trial and error. A variational distance regularization method is utilized in this research to regularize the level set function to be a desired distance-regularized shape. With the distance information embedded in the level set model, the wrapping boundary layer and the interior infill region can be naturally defined. The isotropic infill achieved via the mesoscale topology optimization is conformally fit into the wrapping boundary layer using the shape-preserving conformal mapping method, which leads to a hierarchical physical structure with optimized overall topology and effective infill properties. The proposed method is expected to provide a timely solution to the increasing demand for multiscale and multifunctional structure design.

关键词： concurrent topology optimization parametric level set method cardinal basis function shell-infill structure design conformal mapping

HTML PDF 收藏

Parametric equations for notch stress concentration factors of rib–deck welds under bending loading

《结构与土木工程前沿（英文）》 2021年第15卷第3期页码 595-608 doi: 10.1007/s11709-021-0720-1

摘要： The effective notch stress approach for evaluating the fatigue strength of rib–deck welds requires notch stress concentration factors obtained from complex finite element analysis. To improve the efficiency of the approach, the notch stress concentration factors for three typical fatigue-cracking modes (i.e., root–toe, root–deck, and toe–deck cracking modes) were thoroughly investigated in this study. First, we developed a model for investigating the effective notch stress in rib–deck welds. Then, we performed a parametric analysis to investigate the effects of multiple geometric parameters of a rib–deck weld on the notch stress concentration factors. On this basis, the multiple linear stepwise regression analysis was performed to obtain the optimal regression functions for predicting the notch stress concentration factors. Finally, we employed the proposed formulas in a case study. The notch stress concentration factors estimated from the developed formulas show agree well with the finite element analysis results. The results of the case study demonstrate the feasibility and reliability of the proposed formulas. It also shows that the fatigue design curve of FAT225 seems to be conservative for evaluating the fatigue strength of rib–deck welds.

关键词： notch stress concentration factor rib–deck weld parametric analysis regression analysis parametric equation

HTML PDF 收藏

Building information modeling based on intelligent parametric technology

ZENG Xudong, TAN Jie

《结构与土木工程前沿（英文）》 2007年第1卷第3期页码 367-370 doi: 10.1007/s11709-007-0049-4

摘要： In order to push the information organization process of the building industry, promote sustainable architectural design and enhance the competitiveness of China’s building industry, the author studies building information modeling (BIM) based on intelligent parametric modeling technology. Building information modeling is a new technology in the field of computer aided architectural design, which contains not only geometric data, but also the great amount of engineering data throughout the lifecycle of a building. The author also compares BIM technology with two-dimensional CAD technology, and demonstrates the advantages and characteristics of intelligent parametric modeling technology. Building information modeling, which is based on intelligent parametric modeling technology, will certainly replace traditional computer aided architectural design and become the new driving force to push forward China s building industry in this information age.

HTML PDF 收藏

Seismic fragility curves for structures using non-parametric representations

Chu MAI, Katerina KONAKLI, Bruno SUDRET

《结构与土木工程前沿（英文）》 2017年第11卷第2期页码 169-186 doi: 10.1007/s11709-017-0385-y

摘要： Fragility curves are commonly used in civil engineering to assess the vulnerability of structures to earthquakes. The probability of failure associated with a prescribed criterion (e.g., the maximal inter-storey drift of a building exceeding a certain threshold) is represented as a function of the intensity of the earthquake ground motion (e.g., peak ground acceleration or spectral acceleration). The classical approach relies on assuming a lognormal shape of the fragility curves; it is thus parametric. In this paper, we introduce two non-parametric approaches to establish the fragility curves without employing the above assumption, namely binned Monte Carlo simulation and kernel density estimation. As an illustration, we compute the fragility curves for a three-storey steel frame using a large number of synthetic ground motions. The curves obtained with the non-parametric approaches are compared with respective curves based on the lognormal assumption. A similar comparison is presented for a case when a limited number of recorded ground motions is available. It is found that the accuracy of the lognormal curves depends on the ground motion intensity measure, the failure criterion and most importantly, on the employed method for estimating the parameters of the lognormal shape.

关键词： earthquake engineering fragility curves lognormal assumption non-parametric approach kernel density estimation epistemic uncertainty

HTML PDF 收藏

Innovative seismic retrofitting strategy of added stories isolation system

Min-Ho CHEY, J. Geoffrey CHASE, John B. MANDER, Athol J. CARR

《结构与土木工程前沿（英文）》 2013年第7卷第1期页码 13-23 doi: 10.1007/s11709-013-0195-9

摘要： The seismic performance of “added stories isolation” (ASI) systems are investigated for 12-story moment resisting frames. The newly added and isolated upper stories on the top of the existing structure are rolled to act as a large tuned mass damper (TMD) to overcome the limitation of the size of tuned mass, resulting to “12+2” and “12+4” stories building configurations. The isolation layer, as a core design strategy, is optimally designed based on optimal TMD design principle, entailing the insertion of passive flexible laminated rubber bearings to segregate two or four upper stories from a conventionally constructed lower superstructure system. Statistical performance metrics are presented for 30 earthquake records from the 3 suites of the SAC project. Time history analyses are used to compute various response performances and reduction factors across a wide range of seismic hazard intensities. Results show that ASI systems can effectively manage seismic response for multi-degree-of freedom (MDOF) systems across a broader range of ground motions without requiring burdensome extra mass. Specific results include the identification of differences in the number of added story by which the suggested isolation systems remove energy.

关键词： added stories seismic isolation tuned mass damper parametric optimization statistical method

HTML PDF 收藏

一种基于参数扰动的芯片成品率双目标优化框架

Xin LI,Jin SUN,Fu XIAO,Jiang-shan TIAN

《信息与电子工程前沿（英文）》 2016年第17卷第2期页码 160-172 doi: 10.1631/FITEE.1500168

摘要：

随着收缩技术的发展，工艺，电压和温度（PVT）参数的可变性显着影响了芯片设计的成品率分析和优化。先前的产量估计算法已经限于预测时序或功率产量。但是，忽略功率和延迟之间的相关性将导致明显的产量损失。这些方法中的大多数都还具有较高的计算复杂度和较长的运行时间。我们提出了一种基于Chebyshev仿射算术（CAA）和自适应加权和（AWS）方法的新型双目标优化框架，在该框架中将功率和时序收益两者均设置为目标函数。同时优化两个目标以保持它们之间的相关性。所提出的方法首先在任意相关性的假设下预测泄漏和延迟分布的保证概率边界。然后，通过计算累积分布函数（CDF）边界来建立功率延迟双目标优化模型。最后，将AWS方法应用于功率延迟优化，以生成分布良好的一组Pareto最优解。在ISCAS基准电路上的实验结果表明，该双目标框架能够在功率和时序产量之间提供足够的权衡信息。

关键词：参数变化，参数收益率，多目标优化，切比雪夫仿射，自适应加权和，

HTML PDF 收藏

Parametric oscillation of cables and aerodynamic effect

Yong XIA, Jing ZHANG, Youlin XU, Yozo FUJINO,

《结构与土木工程前沿（英文）》 2010年第4卷第3期页码 321-325 doi: 10.1007/s11709-010-0028-z

摘要： This paper addresses the aerodynamic effect on the nonlinear oscillation, particularly parametric vibration of cables in cable-stayed bridges. A simplified 2-DOF model, including a beam and a stayed cable, is formulated first. Response of the cable under global harmonic excitation which is associated with wind speed is obtained using the multiple scales method. Via numerical analysis, the stability condition of the cable in terms of wind speed is derived. The method is applied to a numerical example and a long-span bridge to analyze its all stay cables. It is demonstrated that very large vibration at one of the longest cables in the middle span of the bridge can be parametrically excited when the wind speed is over around 210 km/h (58.5 m/s).

关键词： parametric vibration cables cable-stayed bridge nonlinear vibration

HTML PDF 收藏

Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed

《结构与土木工程前沿（英文）》页码 1145-1162 doi: 10.1007/s11709-023-0945-2

摘要： To realize seismic-resilient reinforced concrete (RC) moment-resisting frame structures, a novel self-centering RC column with a rubber layer placed at the bottom (SRRC column) is proposed herein. For the column, the longitudinal reinforcement dissipates seismic energy, the rubber layer allows the rocking of the column, and the unbonded prestressed tendon enables self-centering capacity. A refined finite element model of the SRRC column is developed, the effectiveness of which is validated based on experimental results. Results show that the SRRC column exhibits stable energy dissipation capacity and no strength degradation; additionally, it can significantly reduce permanent residual deformation and mitigate damage to concrete. Extensive parametric studies pertaining to SRRC columns have been conducted to investigate the critical factors affecting their seismic performance.

关键词： seismic resilience self-centering rubber layer flag-shaped hysteresis loop parametric study

HTML PDF 收藏

不确定条件下采用精确参数规划的非线性模型过程操作

Vassilis M. Charitopoulos,Lazaros G. Papageorgiou,Vivek Dua

《工程（英文）》 2017年第3卷第2期页码 202-213 doi: 10.1016/J.ENG.2017.02.008

摘要：

本文提出了新的两(多) 参数规划(mp-P) 启发算法以求解混合整数非线性规划(MINLP) 问题，并着重说明了算法在过程综合问题中的应用。对于因对数项导致的非线性，开发了针对确定性问题的参数算法(p-MINLP)。关键之处是通过将二进制变量和(或) 不确定参数作为符号参数重新生成和求解一阶Karush Kuhn Tucker(KKT) 系统的解析表达式。为此，采用了符号处理和求解技术。为了证明所提出的算法的适用性和有效性，对两个过程综合案例研究进行了验证，相应的结果经最新的数值MINLP 求解器验证是有效的。对于p-MINLP，给出了不确定参数的显函数表示的最优解。

关键词：参数规划不确定性过程综合混合整数非线性规划符号操作

HTML PDF 收藏

Parametric study of hexagonal castellated beams in post-tensioned self-centering steel connections

Hassan ABEDI SARVESTANI

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1020-1035 doi: 10.1007/s11709-019-0534-6

摘要： The effects of important parameters (beam reinforcing plates, initial post-tensioning, and material properties of steel angles) on the behavior of hexagonal castellated beams in post-tensioned self-centering (PTSC) connections undergone cyclic loading up to 4% lateral drift have been investigated by finite element (FE) analysis using ABAQUS. The PTSC connection is comprised of bolted top and bottom angles as energy dissipaters and steel strands to provide self-centering capacity. The FE analysis has also been validated against the experimental test. The new formulations derived from analytical method has been proposed to predict bending moment of PTSC connections. The web-post buckling in hexagonal castellated beams has been identified as the dominant failure mode when excessive initial post-tensioning force is applied to reach greater bending moment resistance, so it is required to limit the highest initial post-tensioning force to prevent this failure. Furthermore, properties of steel material has been simulated using bilinear elastoplastic modeling with 1.5% strain-hardening which has perfectly matched with the real material of steel angles. It is recommended to avoid using steel angles with high yielding strength since they lead to the yielding of bolt shank. The necessity of reinforcing plates to prevent beam flange from local buckling has been reaffirmed.

关键词： finite element analysis hexagonal castellated beam parametric study post-tensioned self-centering steel connection steel moment-resisting frame

HTML PDF 收藏

difference analysis of shallow sprayed concrete tunnels crossing a reverse fault or a normal fault: A parametric

Masoud RANJBARNIA, Milad ZAHERI, Daniel DIAS

《结构与土木工程前沿（英文）》 2020年第14卷第4期页码 998-1011 doi: 10.1007/s11709-020-0621-8

摘要： Urban tunnels crossing faults are always at the risk of severe damages. In this paper, the effects of a reverse and a normal fault movement on a transversely crossing shallow shotcreted tunnel are investigated by 3D finite difference analysis. After verifying the accuracy of the numerical simulation predictions with the centrifuge physical model results, a parametric study is then conducted. That is, the effects of various parameters such as the sprayed concrete thickness, the geo-mechanical properties of soil, the tunnel depth, and the fault plane dip angle are studied on the displacements of the ground surface and the tunnel structure, and on the plastic strains of the soil mass around tunnel. The results of each case of reverse and normal faulting are independently discussed and then compared with each other. It is obtained that deeper tunnels show greater displacements for both types of faulting.

关键词： urban tunnel sprayed concrete reverse fault normal fault finite difference analysis