Design Optimization and Safety Evaluation of Cross-Sea Bridge Barrier

2011 ◽  
Vol 97-98 ◽  
pp. 100-107
Author(s):  
Lei Fang ◽  
Liang Zhang ◽  
Shu Ming Yan ◽  
Ning Jia ◽  
Min Jing ◽  
...  
Keyword(s):  
Design Optimization ◽  
Impact Test ◽  
Safety Evaluation ◽  
Full Scale ◽  
Finite Elements Analysis ◽  
Acceptance Criteria ◽  
Analysis And Design ◽  
Bridge Safety ◽  
Study Results ◽  
New Type

By comprehensive analysis and design optimization of barrier structure parameters, a new type of beam-and-post steel barrier was invented according to impact test condition and acceptance criteria of cross-sea bridge barrier. Full-scale impact tests and finite elements analysis were conducted to do safty evalution of the barrier. The results show that, ASI value is 1.62 for test and that is 1.67 for FEA, THIV is 30.7km/h for test and that is 31.2km/h for FEA. Working width is 0.88m for test and that is 0.62m for FEA. Occupant risk evaluation index can meet the requirements of level B and the working width can meet the requirements of level W3. Both of tracking and posture of vehicles are well. The study results above show that safety performance of cross-sea bridge barrier can meet or exceed the acceptance criteria. FEA results are consistent with Full-scale impact test, which validate the reliability of FEA. cross-sea bridge barrier can meet the highest test level for beam-and-post steel barrier, which can defend the out-of-control vehicles effectively and help to ensure the bridge safety.

Correlation Analysis of Computer Simulation with Full-Scale Impact Test for Barrier Safety Evaluation

2011 ◽  
Vol 94-96 ◽  
pp. 2092-2101
Author(s):  
Xin Peng Shao ◽  
Hui Ji ◽  
Shu Ming Yan ◽  
Qi Qian Li ◽  
Ning Jia ◽  
...  
Keyword(s):  
Computer Simulation ◽  
Performance Evaluation ◽  
Impact Test ◽  
Safety Evaluation ◽  
Simulation Models ◽  
Simulation Method ◽  
Full Scale ◽  
Safety Performance ◽  
Computer Simulation Method ◽  
Set Up

In order to analyze the feasibility of barrier safety performance evaluation with computer simulation method, finite-element models of various vehicles and barriers were set up and simulations results are compared to multiple full-scale impact test data. The results indicate that all safety performance index such as vehicle trajectory, structural adequacy, occupant risk and dynamic deformation can be extracted from computer simulation and FEA results are coincident with those of tests with error less than 10%. Computer simulation method is proved to be highly feasible for safety performance evaluation of barriers. The concept that simulation models must be verified through tests is stressed and the suggestion that laws and regulations on professional audit and management of CAE engineers should be completed is brought out.

Biotower Pilot Study Results for a Photographic and Specialty Paper Manufacturer

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2109-2112
Author(s):  
J. G. Cleary ◽  
T. J. Boehm ◽  
R. J. Geary
Keyword(s):  
New York ◽  
Pilot Study ◽  
New York State ◽  
Cross Flow ◽  
Full Scale ◽  
Treatment System ◽  
Salmon River ◽  
Study Results ◽  
Comparable Performance ◽  
Pollutant Discharge

Schoeller Technical Papers, Inc. (Schoeller), which manufactures photographic and other specialty papers, is located in Pulaski, New York. The wastewater treatment system consists of a primary clarifier and two settling lagoons. Secondary treatment using a biotower was proposed to meet the new New York State Pollutant Discharge Elimination System (SPDES) discharge limits for BOD and TSS. The effluent from each basin is discharged directly to the Salmon River, at an approximate average flow of 1.6 million gallons/day (mgd). A biotower pilot study was performed to evaluate the suitability of a biotower treatment process for treating the total effluent from Schoeller's facility. The pilot study was used to select the media for the full-scale biotower and to confirm the design loading for the full-scale biotower, which proceeded in parallel with the pilot study due to the schedule constraints. Two pilot systems were operated to compare a conventional cross-flow and vertical media. Test data were collected to evaluate the performance of each pilot treatment system at a range of loading conditions and to develop the design loading information for the full-scale plant. The pilot units were operated for a period of 10 months. BOD concentrations to the pilot units averaged 58 mg/l with a peak of 210 mg/l. Approximately 80% of the BOD was soluble. BOD loadings averaged 21 lb BOD/day/1,000 cubic feet with a peak of 77 lb BOD/day/1,000 cubic feet. Both pilot units achieved excellent BOD removals exceeding 75%, with average effluent soluble BOD concentration less than 10 mg/l and average effluent TSS concentrations of 12 mg/l. The two media achieved comparable performance throughout most of the pilot study.

scholarly journals Numerical and Experimental Study of Lightning Stroke to BIPV Modules

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 748
Author(s):  
Xiaoyan Bian ◽  
Yao Zhang ◽  
Qibin Zhou ◽  
Ting Cao ◽  
Bengang Wei
Keyword(s):  
Numerical Simulation ◽  
Experimental Study ◽  
Coupling Model ◽  
Maximum Temperature ◽  
Lightning Stroke ◽  
Study Results ◽  
Pv Modules ◽  
New Type ◽  
Metal Frame ◽  
Current Flows

Building Integrated Photovoltaic (BIPV) modules are a new type of photovoltaic (PV) modules that are widely used in distributed PV stations on the roof of buildings for power generation. Due to the high installation location, BIPV modules suffer from lightning hazard greatly. In order to evaluate the risk of lightning stroke and consequent damage to BIPV modules, the studies on the lightning attachment characteristics and the lightning energy withstand capability are conducted, respectively, based on numerical and experimental methods in this paper. In the study of lightning attachment characteristics, the numerical simulation results show that it is easier for the charges to concentrate on the upper edge of the BIPV metal frame. Therefore, the electric field strength at the upper edge is enhanced to emit upward leaders and attract the lightning downward leaders. The conclusion is verified through the long-gap discharge experiment in a high voltage lab. From the experimental study of multi-discharge in the lab, it is found that the lightning interception efficiency of the BIPV module is improved by 114% compared with the traditional PV modules. In the study of lightning energy withstand capability, a thermoelectric coupling model is established. With this model, the potential, current and temperature can be calculated in the multi-physical field numerical simulation. The results show that the maximum temperature of the metal frame increases by 16.07 °C when 100 kA lightning current flows through it and does not bring any damage to the PV modules. The numerical results have a good consistency with the experimental study results obtained from the 100 kA impulse current experiment in the lab.

Running safety evaluation of a 350 km/h high-speed freight train negotiating a curve based on the arbitrary Lagrangian-Eulerian method

2021 ◽  
pp. 095440972098628
Author(s):  
Gongxun Deng ◽  
Yong Peng ◽  
Chunguang Yan ◽  
Boge Wen
Keyword(s):  
High Speed ◽  
Safety Evaluation ◽  
Interaction Model ◽  
Arbitrary Lagrangian Eulerian ◽  
Railway Transportation ◽  
Freight Train ◽  
Fluid Structure ◽  
Running Safety ◽  
Study Results ◽  
Fill Level

To adapt to the rapid growth of the logistics market and further improve the competitiveness of railway transportation, the high-speed freight train with a design speed of 350 km/h is being developed in China. The safety of the train under great axle load of 17 t and dynamic load is unknown. This paper is aimed to study the running safety of the high-speed freight train coupled with various cargo loading conditions negotiating a sharp curve at high velocity. A numerical model integrated a fluid-structure coupled container model and the nonlinear high-speed freight train was set up by the software of LS-DYNA. The fluid-structure interaction model between the container and fluid cargo was established using the Arbitrary Lagrangian-Eulerian (ALE) method. Two influencing parameters, including the cargo state in the container and the fill level, were selected. The study results showed that the wheelset unloading ratio and overturning coefficient could be significantly affected by the liquid sloshing, while the influence of sloshing on the risk of derailment was slight. In general, increasing the cargo filling rate would contribute to vehicle operation safety. In conclusion, this study would provide theoretical help for the running safety of the newly designed high-speed freight train.

scholarly journals Towards a Framework of Operational-Risk Assessment for a Maritime Autonomous Surface Ship

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3879
Author(s):  
Cunlong Fan ◽  
Jakub Montewka ◽  
Di Zhang
Keyword(s):  
Expert Knowledge ◽  
Safety Evaluation ◽  
Manual Control ◽  
Operational Mode ◽  
Surface Ship ◽  
Open Questions ◽  
Study Results ◽  
Operational Modes ◽  
Mass Case

Global research interest in the domain of maritime autonomous surface ships (MASS) is dramatically increasing. With new prototypes planned to be set to the seas where various operational modes (OMs) are claimed, the issue of the safety evaluation of an MASS, and criteria for selecting the appropriate OM for given conditions remain open questions. This paper proposes a four-step risk-informed framework to assess risk in a scenario for an MASS operating at one of three OMs: manual control (MC), remote control (RC), and autonomous control (AC). To this end, the concept of risk priority numbers (RPNs), adopted from failure mode and effects analysis (FMEA), is utilized. The required parameters to defined RPNs are obtained in the course of analyzing a model MASS accident with expert knowledge. The applicability of the proposed framework is demonstrated via a model MASS case study. Results reveal that, in the same scenario, the risk of MASS varied across the analyzed OMs. On the basis of the aggregated results for each operational mode, suggestions for OM switching are put forward.

Criteria for Recovery of Zero Initial Condition Responses of Unstable Plants Under Input Saturation

2000 ◽  
Author(s):  
Wei Wu ◽  
Suhada Jayasuriya
Keyword(s):  
Initial Conditions ◽  
Input Saturation ◽  
Input Sequence ◽  
Feedback System ◽  
Open Loop ◽  
Feedback Systems ◽  
Bounded Control ◽  
Analysis And Design ◽  
Study Results ◽  
Unstable Plant

Abstract In this paper, we consider the sufficient and/or necessary conditions under which responses of unstable plants with zero initial conditions would be bounded under step inputs. Several possible unstable pole patterns are examined, and corresponding criteria are derived. It is shown that an unstable plant can be stabilized to have bounded responses using an alternate step input sequence. Step inputs simulate the saturated inputs in a feedback system with bounded control, where the closed-loop stability of an unstable plant is really difficult to study. Results from this open-loop study may lend some insight into the analysis and design of such feedback systems under input saturation nonlinearities.

Defective Pipeline Fatigue-Life Prediction Using Failure Assessment Diagram Technique

2004 ◽  
Author(s):  
Jinheng Luo ◽  
Xinwei Zhao ◽  
Qingren Xiong ◽  
Chunyong Huo
Keyword(s):  
Fatigue Life ◽  
Evaluation System ◽  
Life Prediction ◽  
Safety Evaluation ◽  
Load Ratio ◽  
Test System ◽  
Full Scale ◽  
Oil Pipeline ◽  
Failure Assessment Diagram ◽  
Failure Assessment

The life prediction, whose results can be used to define the inspection, repair or replacement cycle of in-service pipeline, is a main component of safety assessment of gas and oil pipeline. At present, failure Assessment Diagram (FAD) technique has been widely used in quantitative engineering safety evaluation system of pipeline that contains crack-like flaws. In past work, the authors developed a very useful model to predict the fatigue life of defective pipeline and established a computer calculating method. Based on FAD technique, toughness ratio and load ratio are calculated repeatedly with every crack increment in the model. With the self-developed full-scale test system, the full-scale pipe fatigue test was collected to verify the applicability of this method.

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