Seismic retrofitting techniques using an energy absorption segment for steel bridge piers

Chapter 12 - Pseudo-Dynamic Tests and Analysis on Semi-Rigidly Jointed Steel Frames

Evaluation of the microscale structure and performance of asphalt mixtures under different design methods

Steel tubular bridge pier with inner cruciform plates has high seismic performance. In this paper, the applicability of static-dynamic verification method for seismic design of steel tubular bridge piers with inner cruciform plates is studied. The ultimate strength and state of steel tubular stub columns with inner cruciform plate subjected to compression and bending were investigated through finite element analysis. The validity of the proposed design formula of the failure strain which was obtained from the stub column analysis was examined by analysis on tubular steel bridge piers with inner cruciform plates under cyclic loading. The dynamic response analysis of the same steel bridge piers was carried out on the basis of the spring-mass model and the fiber element model. These results indicated the static-dynamic verification method of the seismic response analysis through the spring-mass model are good agreement with dynamic verification method of seismic response analysis by the fiber element model.

Steel ConstructionVolume 16, Issue 1 p. 1-1 EditorialFree Access 23rd International Colloquium on Stability and Ductility of Steel Structures, University of Aveiro Paulo Vila Real, Paulo Vila Real SDSS 2022 ChairmanSearch for more papers by this authorNuno Lopes, Nuno Lopes SDSS 2022 Co-chairmanSearch for more papers by this author Paulo Vila Real, Paulo Vila Real SDSS 2022 ChairmanSearch for more papers by this authorNuno Lopes, Nuno Lopes SDSS 2022 Co-chairmanSearch for more papers by this author First published: 09 February 2023 https://doi.org/10.1002/stco.202370103AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume16, Issue1February 2023Pages 1-1 RelatedInformation

In this paper, we propose an efficient design method for a thermal camera with continuous zoom based on the research and manufacturing experience of the thermal camera. In addition, it is divided into system design method, optical design method, mechanical design method, and electronic design method. First, we propose an effective NUC compensation method and a lens-specific sensitivity design method in terms of system. Second, we propose a zoom trajectory design method considering the temperature effect on the optical aspect. Third, it suggests the minimization of optical axis shaking between magnification conversion in terms of mechanism. Finally, we propose a lens-specific temperature compensation method and a speed conversion algorithm according to the zoom interval as an electronic aspect.

Reliability of design approaches for axially loaded offshore piles and its consequences with respect to the North Sea

Seismic design method analyses of an innovative steel damping bearing for railway bridges

The design of p-cycles in WDM mesh networks has been extensively studied. However, most of studies only deal with a single link failure rather than node failure. In this paper, we develop a new scalable and efficient design method for computing node-protecting p-cycles. The performance of our new proposed design method makes an obvious improvement 20% in capacity redundancy over that of the previous design method. The conventional design methods formulate the problem of pcycle design as an Integer Linear Program (ILP). To solve the ILP, the prerequisite is to a priori enumerated all possible pcycle candidates. For a large network, the resulting ILP maybe intractable as the huge number of cycles may exist. We propose a new design and solution method based on large scale optimization tools, namely Column Generation (CG), where pcycles are generated on-line when needed. The main advantage of our CG-based method is that no p-cycles are a-priori off-line enumerated, the generation of the promising set of p-cycles is embedded in the optimization process. Extensive experiments on several network instances have been conducted for comparison. Experimental results show that our new proposed methods outperforms the previous method in terms of capacity efficiency.

Asphalt treated base (ATB) materials have shown good road performance. There are some differences in the mix design methods used for ATB and Asphalt Concrete (AC) and this paper investigates four different design methods for ATB. Each design method is analyzed by using volume and mechanical indexes, and pavement performance. Based on this analysis, the proper design method of ATB is proposed. 1. ATB Design Method This paper describes the comparison of experimental data with specification criteria recommend in the SUPERPAVE method, the Bailey method, and a mechanical method. The analysis includes determining the effect of different design methods on asphalt pavement performance.

An efficient technique of designing spatial matrix filter for array signal preprocessing based on convex programming was proposed. Five methods were considered for designing the filter. In design method 1, we minimized the passband fidelity subject to the controlled overall stopband attenuation level. In design method 2, the objective function and the constraint in the design method 1 were reversed. In design method 3, the optimal matrix filter which has the general mean square error was considered. In design method 4, the left stopband and the right stopband were constrained with specific attenuation level each, and the minimized passband fidelity was received. In design method 5, the optimization objective function was the sum of the left stopband and the right stopband attenuation levels with the weighting factors 1 andγ, respectively, and the passband fidelity was the constraints. The optimal solution of the optimizations above was derived by the Lagrange multiplier theory. The relations between the optimal solutions were analyzed. The generalized singular value decomposition was introduced to simplify the optimal solution of design methods 1 and 2 and enhanced the efficiency of solving the Lagrange multipliers. By simulations, it could be found that the proposed method was effective for designing the spatial matrix filter.

Design method for relief well trajectory to avoid side-track operations and control the relative distance

Structural behaviour of cold-formed thin-walled short steel channel columns at elevated temperatures. Part 2: Design calculations and numerical analysis

This paper designs and optimizes a new structure hybrid material B‐pillar assembly. Establish a finite element analysis model for the side impact test of an electric vehicle to verify the model's accuracy. Construct a finite element model of the hybrid material B‐pillar assembly. Combined with the static performance analysis of the B‐pillar, the laminate design of the carbon fiber composite B‐pillar reinforcement plate and optimization. For the outer and inner panels of the B‐pillar, the surrogate model method and the multiobjective optimization method are combined to set 11 design variables and 13 responses. The optimal Latin hypercube design method was used to randomly sample each design variable and fit the radial basis function (RBF) approximate model. The modified second‐generation non‐dominated sorting genetic algorithm (MNSGA‐II) was used to carry out multiobjective optimization of the mixed material B‐pillar assembly, and the multicriteria decision‐making method was used to obtain the optimal solution for the Pareto solution set. A drop weight impact test was performed on the hybrid material B‐pillar assembly. The results showed that the peak collision force of the hybrid material B‐pillar was reduced by 43.7% compared with the original steel B‐pillar, the specific energy absorption was increased by 17.5%, and the side impact safety performance was better. After optimization, the weight of the mixed material B‐column was reduced by 26.44%. The improvement rates of the intrusion amount at P2 and the intrusion speed at P1 were 23.99% and 0.63%, respectively, and the lightweight effect and side impact safety were significantly improved.Highlights The finite element analysis parameters of carbon fiber composite materials were constructed through experiments, and the basis for simulation analysis under various working conditions of the B‐pillar based on performance‐driven optimization was established. A hybrid material B‐pillar design method is proposed, which consists of a variable‐thickness high‐strength steel B‐pillar outer plate, a variable‐thickness high‐strength steel B‐pillar inner plate, and a carbon fiber composite B‐pillar reinforcement plate. The super layer of the carbon fiber composite B‐pillar reinforcement plate was optimized and the laying plan of the carbon fiber composite B‐pillar reinforcement plate was determined. Performance‐driven optimization is adopted to realize the collaboration of multilevel design and optimization methods such as B‐pillar conceptual design, detailed design, and multiobjective optimization. A modified NSGA‐II algorithm was proposed and combined with the multicriteria decision‐making method and the entropy‐weighted gray relation analysis method to determine the Pareto optimal solution and the optimal design scheme for the mixed material B‐pillar.

Centrifugal pump is widely used in various fields of the national economy. Pumps, of which 70% are centrifugal pumps, consume 20.9% of the total electricity generation nationwide in China in 2009, according to the statistics. In this paper, the research advances in design methods and characteristics of internal flow fields for centrifugal pumps, carried out by the Research Center of Fluid Machinery Engineering and Technology of Jiangsu University, is introduced. First of all, the Greater Flow Design method, Non-Overload Design method and Splitter Blade Offset Design method are fully discussed through systematically studies. In addition, three methods of performance prediction for centrifugal pumps are adopted, and a CAD/CFD software for hydraulic design and analysis is initially developed. Secondly, to deepen the understanding of characteristics of internal flow in centrifugal pumps, the numerical simulation and PIV measurement investigation have been done. Then the unsteady flow induced vibration and noise are studied considering fluid-structure interaction and fluid-sound interaction. The control of the unsteady flow in centrifugal pumps is also attempted to optimize the design method for centrifugal pumps. In addition, the pressure pulsation and vibration behaviors under both cavitation and non-cavitation conditions are obtained and analyzed. Finally, some detecting methods and criterion for cavitation incipiency and development are put forward.

Design of drainage culverts considering critical storm duration