Different Failure Modes of a Clay Foundation-Embankment System Corresponding to Different Incident Seismic Waves

2010 ◽  
Author(s):  
Kentaro Nakai ◽  
Toshihiro Noda ◽  
Akira Asaoka
Keyword(s):  
Seismic Waves ◽  
Failure Modes

scholarly journals An Energy-Based Safety Evaluation Index of Blast Vibration

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Mingsheng Zhao ◽  
Dong Huang ◽  
Maosen Cao ◽  
En-an Chi ◽  
Jun Liu ◽  
...  
Keyword(s):  
Seismic Waves ◽  
Failure Modes ◽  
Guizhou Province ◽  
Damage Potential ◽  
Blast Vibration ◽  
Restoring Force ◽  
Safety Criterion ◽  
Plastic Damage ◽  
Field Investigations ◽  
Blast Vibrations

The combined peak particle velocity (PPV) and frequency safety criterion for blast vibration is widely used in blasting engineering. However, some field investigations are inconsistent with this criterion. On the basis of field investigations, it is found that there are two failure modes of structures subjected to blasting seismic waves, that is, first-excursion failure and cumulative plastic damage failure. Moreover, the nature of structural responses under blast vibrations is a process of energy input, transformation, and dissipation. Therefore, an energy-based dual safety standard is proposed in this work to more comprehensively explain all failure modes of structures under blast vibrations. To this end, structures are simplified into elastic-plastic single degree of freedom (SDOF) systems with bilinear restoring force models, and energy responses of SDOF systems are then determined using theNewmark-βmethod. From the energy responses, the maximum instantaneous input energy and hysteretic energy are selected as the basis of the dual safety criterion, because they can reflect first-excursion failure and cumulative plastic damage failure, respectively. Finally, field investigations in a blasting site in Zunyi, Guizhou province, China, are used to prove that compared to the PPV-frequency criterion the proposed energy-based dual safety criterion is more capable of assessing the damage potential of blast vibrations.

Study on Failure Mode for Power Intake Structure under Seismic Action

2013 ◽  
Vol 438-439 ◽  
pp. 1537-1541
Author(s):  
Lin Gang Tian ◽  
Bin Bin Zhen ◽  
Hu Huang ◽  
Jing Shen
Keyword(s):  
Failure Mode ◽  
Seismic Waves ◽  
Failure Modes ◽  
Seismic Analysis ◽  
Failure Process ◽  
Early Period ◽  
Seismic Load ◽  
Seismic Action ◽  
High Intake ◽  
Ultimate Failure

This paper studies on the ultimate failure modes and bearing capacity of high intake tower under the action of seismic load based on nonlinear concrete model. By monitoring the way of crack development and failure process of the tower to study failure mode under the action of various seismic wave, we can conclud that the regional distributions of the structural crack of tower body vary with the duration of an earthquake. In the early period of earthquake, the crack has little effect on the whole structure. After duration of the earthquake, the structure forms penetrable cracks. By studying the cracks development and distribution on the structure of tower body under the action of various seismic waves, we know the failure process and failure mode of high intake tower. The conclusions provide evidence for engineering design and seismic analysis of pertinent engineering.

scholarly journals Research on Collapse Process of Cable-Stayed Bridges under Strong Seismic Excitations

2017 ◽  
Vol 2017 ◽  
pp. 1-18 ◽  
Author(s):  
Xuewei Wang ◽  
Bing Zhu ◽  
Shengai Cui
Keyword(s):  
Seismic Waves ◽  
Failure Modes ◽  
Failure Process ◽  
Seismic Excitations ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Collapse Failure ◽  
Main Girder ◽  
Collapse Process ◽  
Cable Stayed Bridges

In order to present the collapse process and failure mechanism of long-span cable-stayed bridges under strong seismic excitations, a rail-cum-road steel truss cable-stayed bridge was selected as engineering background, the collapse failure numerical model of the cable-stayed bridge was established based on the explicit dynamic finite element method (FEM), and the whole collapse process of the cable-stayed bridge was analyzed and studied with three different seismic waves acted in the horizontal longitudinal direction, respectively. It can be found from the numerical simulation analysis that the whole collapse failure process and failure modes of the cable-stayed bridge under three different seismic waves are similar. Furthermore, the piers and the main pylons are critical components contributing to the collapse of the cable-stayed bridge structure. However, the cables and the main girder are damaged owing to the failure of piers and main pylons during the whole structure collapse process, so the failure of cable and main girder components is not the main reason for the collapse of cable-stayed bridge. The analysis results can provide theoretical basis for collapse resistance design and the determination of critical damage components of long-span highway and railway cable-stayed bridges in the research of seismic vulnerability analysis.

Failure Modes-Based Searching and Optimizing of Steel Reinforced Concrete Frame Structures

2014 ◽  
Vol 578-579 ◽  
pp. 691-694
Author(s):  
Yan Fang Zhu ◽  
Bing Xiong ◽  
Zhi Qiang Li
Keyword(s):  
Reinforced Concrete ◽  
Seismic Waves ◽  
Failure Modes ◽  
Optimization Methods ◽  
Frame Structure ◽  
Reinforced Concrete Frame ◽  
Steel Reinforced Concrete ◽  
Concrete Frame ◽  
Reinforced Concrete Frame Structure ◽  
Reinforced Concrete Frame Structures

Taking the optimization of steel reinforced concrete frame structure as background, the searching and optimizing of structural were taken as optimization objectives by introducing failure modes. Incremental dynamic analysis (IDA) was used to search the seismic wave, which had important significance of the structure, thus, the failure modes under the seismic waves could be obtained. And three optimization methods were proposed. Finally, an example was analyzed to verify the rationality of the proposed optimization thought and method.

Scanning Electron Microscopy in Hybrid Microelectronics

1976 ◽  
Vol 34 ◽  
pp. 456-457
Author(s):  
S. Khadpe ◽  
R. Faryniak
Keyword(s):  
Integrated Circuits ◽  
Thick Film ◽  
Integrated Circuit ◽  
Failure Modes ◽  
Three Dimensional ◽  
Circuit Components ◽  
Hybrid Microcircuit ◽  
Electrical Connections ◽  
Scanning Electron

The Scanning Electron Microscope (SEM) is an important tool in Thick Film Hybrid Microcircuits Manufacturing because of its large depth of focus and three dimensional capability. This paper discusses some of the important areas in which the SEM is used to monitor process control and component failure modes during the various stages of manufacture of a typical hybrid microcircuit.Figure 1 shows a thick film hybrid microcircuit used in a Motorola Paging Receiver. The circuit consists of thick film resistors and conductors screened and fired on a ceramic (aluminum oxide) substrate. Two integrated circuit dice are bonded to the conductors by means of conductive epoxy and electrical connections from each integrated circuit to the substrate are made by ultrasonically bonding 1 mil aluminum wires from the die pads to appropriate conductor pads on the substrate. In addition to the integrated circuits and the resistors, the circuit includes seven chip capacitors soldered onto the substrate. Some of the important considerations involved in the selection and reliability aspects of the hybrid circuit components are: (a) the quality of the substrate; (b) the surface structure of the thick film conductors; (c) the metallization characteristics of the integrated circuit; and (d) the quality of the wire bond interconnections.

Human reliability in non-destructive inspections of nuclear power plant components: modeling and analysis

2019 ◽  
Vol 7 (2B) ◽  
Author(s):  
Vanderley Vasconcelos ◽  
Wellington Antonio Soares ◽  
Raissa Oliveira Marques ◽  
Silvério Ferreira Silva Jr ◽  
Amanda Laureano Raso
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Human Factors ◽  
Nuclear Power ◽  
Power Plants ◽  
Failure Modes ◽  
Cooling System ◽  
Human Reliability ◽  
Non Destructive ◽  
Plant Components

Non-destructive inspection (NDI) is one of the key elements in ensuring quality of engineering systems and their safe use. This inspection is a very complex task, during which the inspectors have to rely on their sensory, perceptual, cognitive, and motor skills. It requires high vigilance once it is often carried out on large components, over a long period of time, and in hostile environments and restriction of workplace. A successful NDI requires careful planning, choice of appropriate NDI methods and inspection procedures, as well as qualified and trained inspection personnel. A failure of NDI to detect critical defects in safety-related components of nuclear power plants, for instance, may lead to catastrophic consequences for workers, public and environment. Therefore, ensuring that NDI is reliable and capable of detecting all critical defects is of utmost importance. Despite increased use of automation in NDI, human inspectors, and thus human factors, still play an important role in NDI reliability. Human reliability is the probability of humans conducting specific tasks with satisfactory performance. Many techniques are suitable for modeling and analyzing human reliability in NDI of nuclear power plant components, such as FMEA (Failure Modes and Effects Analysis) and THERP (Technique for Human Error Rate Prediction). An example by using qualitative and quantitative assessesments with these two techniques to improve typical NDI of pipe segments of a core cooling system of a nuclear power plant, through acting on human factors issues, is presented.

Corrosion of Electronic and Magnetic Devices and Materials

1996 ◽  
Vol 451 ◽  
Author(s):  
Gerald S. Frankel
Keyword(s):  
Thin Film ◽  
Failure Modes ◽  
Galvanic Corrosion ◽  
Potential Drop ◽  
Magnetic Devices ◽  
Disk Structure ◽  
Magnetic Layers ◽  
Ohmic Potential Drop ◽  
Corrosion Problem ◽  
Corrosion Susceptibility

ABSTRACTCorrosion of thin film structures commonly used in electronic and magnetic devices is discussed. Typical failure modes are presented, and galvanic corrosion is discussed in some detail since it is one common problem with such devices. A graphical explanation for the determination of the ohmic potential drop during galvanic corrosion is presented. The corrosion problem of thin film disks is shown to have changed during the past ten years owing to changes in disk structure. The corrosion susceptibility of two antiferromagnetic alloys used for exchange coupling to soft magnetic layers is discussed.

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