scholarly journals Experimental and Numerical Investigations of Pressure Field of Curved Shell Structure Subjected to Interior Blast

2019 ◽  
Vol 2019 ◽  
pp. 1-16
Author(s):  
Jialu Ma ◽  
Feng Fan ◽  
Lingxin Zhang ◽  
Chengqing Wu ◽  
Xudong Zhi
Keyword(s):  
Terrorist Attack ◽  
Blast Loading ◽  
Simulation Method ◽  
Time Data ◽  
Blast Pressure ◽  
Long Span ◽  
Pressure Fields ◽  
Pressure Time ◽  
Loading Tests ◽  
Reticulated Domes

A terrorist attack on a long-span spatial structure would cause horrible results. Therefore, it is important to determine the characteristics of blast pressure fields to protect such structures. In this study, fully confined blast loading tests were conducted using a rigid curved shell model, which had an inner space similar to that of a reticulated dome. Four different scenarios were carried out to record the blast loading on five typical positions. The blast pressure-time data were compared and analyzed. In addition, a suitable numerical simulation method was proposed for the issues involved in interior blast loading. This numerical model was verified by comparing with the test data. A parametrical analysis of the interior blast simulations was conducted based on this numerical method. The blast loading values at specific positions were obtained with the key parameters varied within a reasonable scope. The blast loading from blast tests and simulations were presented. On this basis, the interior blast loading could conveniently be predicted by using the method and data in this paper, which could be used in the protective design of other reticulated domes.

Investigation of Effects of Baffle Configuration on the Performance of a Fixed-Cone Valve by Gas-Liquid Two-Phase Model

2012 ◽  
Vol 166-169 ◽  
pp. 1824-1829
Author(s):  
W.L. Wei ◽  
B. Lv ◽  
Y.L. Liu ◽  
X.F. Yang
Keyword(s):  
Numerical Simulation ◽  
Energy Dissipation ◽  
Turbulent Flow ◽  
Average Velocity ◽  
Simulation Method ◽  
Velocity Fields ◽  
Two Phase ◽  
Pressure Fields ◽  
New Type ◽  
Conventional Type

Nested type Fixed-Cone Valve, numerical simulation, energy dissipating, turbulent flow Abstract: In this paper, In this paper, a new type of Fixed-Cone Valve was proposed by improving the conventional type Fixed-Cone Valve .The flow fields of the two kinds of Fixed-Cone Valves were studied by using numerical simulation method .The computed pressure fields and the velocity fields were analyzed ,which shows that under the same conditions ,and by using the nested Fixed-Cone valve, the pressure of the upstream pipe and the cone valve and the average velocity along the downstream pipeline are reduced ,but the rate of energy dissipation is increased.

Rush Repair Method and Suggestion of Long-Span Arch Bridge in Wartime

2012 ◽  
Vol 538-541 ◽  
pp. 3211-3214
Author(s):  
Li He ◽  
Yong Jiu Qian
Keyword(s):  
Damage Assessment ◽  
Research Work ◽  
Blast Loading ◽  
Arch Bridge ◽  
Repair Method ◽  
Long Span ◽  
Future War ◽  
Arch Bridges ◽  
Damage Condition ◽  
Modern War

The enemies pay much attention to the opponent significant bridge in modern war and future war. A number of long-span arch bridges are damaged by blast loading. According to the damage condition and damage assessment of long-span arch bridge subjected to blast loading, a variety of methods suitable for rush repair in wartime are summarized, the rationalization proposals of enhancing anti-blast ability of long-span arch bridge are proposed. The research work is meaningful for the rush repair of long-span arch bridge.

Parametric Sensitivity Analysis of Long-Span Arch-Truss String Structure

2014 ◽  
Vol 919-921 ◽  
pp. 193-198
Author(s):  
Zheng Xian Bai ◽  
Xi Ming Hou ◽  
Shuai Tian ◽  
Jin Zhi Wu
Keyword(s):  
Sensitivity Analysis ◽  
Natural Frequencies ◽  
Simulation Method ◽  
Effective Area ◽  
Monte Carlo Simulation Method ◽  
Sectional Area ◽  
Static Behavior ◽  
Parametric Sensitivity ◽  
Long Span ◽  
String Structure

Parametric sensitivity to static behavior and dynamic characteristics of Long-span Arch-truss String Structures (ATSS), which is based on statistical distribution of parameter errors including elastic modulus of the material, effective area and pre-stress of cable, and thickness of steel pipe, etc., was studied by Monte Carlo simulation method of ANSYS. The error of sectional area of cable is found to be the most sensitive parameter and the natural frequencies are greatly sensitive to the errors of modulus of members. The results help to determine suitable updating parameters of ATSS, and provide valuable advices to guide the construction control.

Seismic Response Analysis of the Numerical Simulation Method on Cable-Stayed Bridge Tower which Considers the Rigid Foundation

2014 ◽  
Vol 875-877 ◽  
pp. 998-1002
Author(s):  
Wei Bing Luo ◽  
Ji Ming Fan ◽  
Ji Lv ◽  
Li Ya Zhang ◽  
Cui Cui Wu
Keyword(s):  
Seismic Response ◽  
Ground Motions ◽  
Simulation Method ◽  
Response Analysis ◽  
Rigid Foundation ◽  
Seismic Responses ◽  
Near Fault ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Bridge Tower

The seismic responses under the action of far-fault and near-fault ground motions of the bridge tower structure of the long-span cable-stayed bridge are numerically discussed by means of the model of the bottom consolidation of the column. The results show that the responses of tower of the cable-stayed bridge correlate well with the properties of the ground motions. The seismic responses of the model have much larger values under the near-fault velocity pulse-like ground motions than those of the counterpart. The frequency of system reduces as the flexibility of structure decreases because of the rigid foundation; The displace response of tower shows that the rigid foundation has little influence on the seismic response of the cable-stayed bridge, while the acceleration response of the tower implies that rigid foundation has adverse effect. Thus, consideration of the soil-pile-superstructure interaction can be meaningful both in theory and reality during the seismic design of long-span cable-stayed bridge structure.

Simulating the Response of Composite Reinforced Floor Slabs Subjected to Blast Loading

2003 ◽  
Author(s):  
Darell Lawver ◽  
Raymond Daddazio ◽  
Gwang Jin Oh ◽  
C. K. B. Lee ◽  
Allan B. Pifko ◽  
...  
Keyword(s):  
Fiber Composite ◽  
Terrorist Attack ◽  
Structural Response ◽  
High Strength ◽  
Reinforcing Bars ◽  
Blast Pressure ◽  
Floor Slab ◽  
Blast Overpressure ◽  
Floor Slabs ◽  
Tensile Forces

The threat of terrorist attack against civil infrastructure in the US and other countries has led to the need to better understand the response of structures and structural components to an impulsive air blast overpressure. One scenario that is present in many cities is delivery trucks entering basement or street level loading/unloading areas. A bomb present in one of these delivery trucks could cause considerable damage to the floor slab (and consequently the building) above the blast by causing a vertical uplift, a condition that the slab was not designed to resist. Traditional methods to retrofit floor slabs to resist an upwards blast pressure require that additional tension sustaining reinforcing bars (rebars) be placed near the slab upper surface. This reinforcing method is costly, difficult to produce, and adds additional weight to the overall structure in building retrofit situations. Another approach to reinforcing the slab is to bond light-weight, high strength fiber composite material to the slab upper surface as a means of resisting the tensile forces from the slab upward motion. This paper presents results from an effort to simulate the response of a reinforced concrete floor slab with a fiber composite retrofit subjected to a blast overpressure. The simulations were performed using the Weidlinger Associates’ FLEX [1] finite element code for structural response calculations. The MAZ [2] computational fluid dynamics code was used to generate blast pressure. This paper will discuss the modeling effort used to predict the response of fiber composite retrofitted slabs and compare the computational analysis to test results1.

scholarly journals Estimating outflow facility parameters for the human eye using hypotensive pressure-time data

PLoS ONE ◽  
2020 ◽  
Vol 15 (8) ◽  
pp. e0238146
Author(s):  
David W. Smith ◽  
Chang-Joon Lee ◽  
Bruce S. Gardiner
Keyword(s):  
Time Data ◽  
Outflow Facility ◽  
Human Eye ◽  
Pressure Time
Sign in / Sign up

Export Citation Format

Share Document