Structural response of corrugated plates under blast loading: The influence of the pressure-time history

In design of ships and ship-shaped offshore units, issues related to impact pressure actions arising from sloshing, slamming, green water, or explosion are of particular concern. The structural response under impact pressure actions is quite different from that under static or quasistatic actions. It has been recognized that the limit state approach is a more rational basis for structural design and safety assessment where both "demand" (loads) and "capacity" (strength) must be accurately defined. For impact pressure action cases, the demand is associated with hydrodynamics areas, taking into account the characteristics of impact pressure-time history, and the structural capacity is associated with structural mechanics areas, considering geometric and material nonlinearities together with strain rate sensitivity. This paper reviews recent advances and trends toward future limit state design of ships and offshore structures under impact pressure actions.

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Numerical Prediction of Sloshing Loads in Ship Tanks

Volume 5: Materials Technology; CFD and VIV ◽

10.1115/omae2008-57312 ◽

2008 ◽

Cited By ~ 1

Author(s):

Sanjay P. Singh ◽

Anant Lal ◽

Sharad S. Dhavalikar

Keyword(s):

Structural Response ◽

Time History ◽

Ship Motions ◽

Flow Solver ◽

Structural Rules ◽

Ansys Cfx ◽

Pressure Time ◽

Fill Level ◽

Common Structural Rules ◽

Oil Tankers

The present work is about the estimation of sloshing loads in partially filled tanks of a ship for design purpose. Two oil tankers of different dimensions were taken for this study. Ship motions for several wave-heading angles were computed using potential flow solver. Relevant period for sloshing was determined based on the seakeeping analysis. Critical fill levels of the tanks (with respect to sloshing) were identified from all possible set of motions. The numerical simulation of tank fluid motions for critical fill level was performed, using general fluid flow solver, ANSYS CFX. Prior to applying the method to ship tanks a validation study was carried out. The method was validated against the experimental results obtained by Hinatsu et al. (2001). Pressures at various locations of the tank were computed and were compared with the Common Structural Rules for Oil Tankers (CSR). Pressure time history obtained from computational fluid dynamics (CFD) simulations was applied on the tank bulkhead to get the structural response, using ANSYS Mechanical.

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Experimental Investigation of Invar Edge Effect in Membrane LNG Tanks

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 4 ◽

10.1115/omae2010-20868 ◽

2010 ◽

Author(s):

Mateusz Graczyk ◽

Kjetil Berget ◽

Joachim Allers

Keyword(s):

Fluid Motion ◽

Structural Response ◽

Time History ◽

Pressure Profile ◽

Pressure Effects ◽

Local Pressure ◽

Temporal And Spatial Distribution ◽

Containment System ◽

Pressure Time ◽

Time Histories

Sloshing, a violent fluid motion in tanks is of current interest for many branches of the industry, among them gas shipping. Although different methods are commonly combined for analyzing sloshing in LNG carriers, time histories of the pressure in the tanks are most reliably obtained by experiments. Very localized pressures may be important for the structural response of the tank containment system. Moreover, the typical pressure time history duration is similar to the structural natural frequency. Therefore, pressure measurements need to be performed with due account for temporal and spatial distribution. This requires a high sampling resolution both in time and space. Fine spatial resolution becomes especially important when local pressure effects are of interest, such as pressure profile passing a membrane corrugation of Mark III containment or Invar edge of No.96 containment. In this paper experimental approach applied by MARIN-TEK for analyzing sloshing phenomenon is presented. The focus is put on investigating effects of Invar edges. A transverse 2D model of a typical LNG carrier is used. Local pressure effects are investigated based on low filling level tests with different wall surfaces: smooth and with horizontal protrusions representing the surface similar to the No.96 containment system.

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Single-Degree-of-Freedom Based Pressure-Impulse Diagrams for Blast Damage Assessment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.567.499 ◽

2014 ◽

Vol 567 ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

Zubair Imam Syed ◽

Mohd Shahir Liew ◽

Muhammad Hasibul Hasan ◽

Srikanth Venkatesan

Keyword(s):

Damage Assessment ◽

Structural Response ◽

Blast Loading ◽

Computational Effort ◽

Degree Of Freedom ◽

Negative Phase ◽

Single Degree Of Freedom ◽

Pressure Impulse ◽

Single Degree ◽

Structural Resistance

Pressure-impulse (P-I) diagrams, which relates damage with both impulse and pressure, are widely used in the design and damage assessment of structural elements under blast loading. Among many methods of deriving P-I diagrams, single degree of freedom (SDOF) models are widely used to develop P-I diagrams for damage assessment of structural members exposed to blast loading. The popularity of the SDOF method in structural response calculation in its simplicity and cost-effective approach that requires limited input data and less computational effort. The SDOF model gives reasonably good results if the response mode shape is representative of the real behaviour. Pressure-impulse diagrams based on SDOF models are derived based on idealised structural resistance functions and the effect of few of the parameters related to structural response and blast loading are ignored. Effects of idealisation of resistance function, inclusion of damping and load rise time on P-I diagrams constructed from SDOF models have been investigated in this study. In idealisation of load, the negative phase of the blast pressure pulse is ignored in SDOF analysis. The effect of this simplification has also been explored. Matrix Laboratory (MATLAB) codes were developed for response calculation of the SDOF system and for repeated analyses of the SDOF models to construct the P-I diagrams. Resistance functions were found to have significant effect on the P-I diagrams were observed. Inclusion of negative phase was found to have notable impact of the shape of P-I diagrams in the dynamic zone.

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Second Paper: Deep Drawing and Free Forming Using a Water Hammer Technique

Proceedings of the Institution of Mechanical Engineers ◽

10.1243/pime_proc_1964_179_019_02 ◽

1964 ◽

Vol 179 (1) ◽

pp. 222-233 ◽

Cited By ~ 3

Author(s):

A. P. Vafiadakis ◽

W. Johnson ◽

I. S. Donaldson

Keyword(s):

Deep Drawing ◽

Time History ◽

Water Hammer ◽

High Rate ◽

Pressure Time ◽

Order Of Magnitude ◽

History Of ◽

Overall Efficiency ◽

Initial Movement ◽

Better Than

Earlier work on a water-hammer technique for high-rate forming of sheet metal has been extended to include work on deep drawing using lead plugs. A study of the pressure-time history of a deforming blank during its initial movement is reported. An assessment of the overall efficiency of the process has been made and is found to be about 50 per cent; this is an order of magnitude better than that found with comparable electro-hydraulic and explosive methods.

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Application of Earthquake Resistance Analysis Technique in the Design of Constructional Engineering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.4482 ◽

2013 ◽

Vol 756-759 ◽

pp. 4482-4486

Author(s):

Chun Gan ◽

Xue Song Luo

Keyword(s):

Response Spectrum ◽

Structural Response ◽

Time History ◽

Economic Losses ◽

Element Analysis ◽

Architectural Engineering ◽

Analysis Technique ◽

History Analysis ◽

Earthquake Resistant ◽

History Of

In recent years, frequent earthquakes have caused great casualties and economic losses in China. And in the earthquake, damage of buildings and the collapse is the main reason causing casualties. Therefore, in the design of constructional engineering, a seismicity of architectural structure is the pressing task at issue. Through time history analysis method, this paper analyzes the time history of building structural response and then it predicts the peak response of mode by response spectrum analysis. Based on this, this paper constructs a numerical simulation model for the architecture by using finite element analysis software SATWE. At the same time, this paper also calculates the structure seismic so as to determine the design of each function structure in architectural engineering design and then provides reference for the realization of earthquake-resistant building.

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The effect of seismic base isolation on structural response of a 12-story hotel building in Padang, Indonesia

E3S Web of Conferences ◽

10.1051/e3sconf/202015605026 ◽

2020 ◽

Vol 156 ◽

pp. 05026

Author(s):

Fauzan ◽

Afdhalul Ihsan ◽

Mutia Putri Monika ◽

Zev Al Jauhari

Keyword(s):

Base Isolation ◽

Response Spectrum ◽

Soft Soil ◽

Structural Response ◽

Time History ◽

Seismic Zone ◽

Isolation System ◽

Rubber Bearing ◽

Seismic Base Isolation ◽

The City

The amount of potential investment in Padang City, Indonesia since 2017 attracted many investors to contribute to the city. One of the investments is a 12-story hotel that will be constructed in By Pass Street of the city. The hotel is located in a high seismic zone area, so the seismic base isolation has been proposed to be used in the hotel building. The main aim of using a seismic base isolation device is to reduce the inertia forces introduced in the structure due to earthquakes by shifting the fundamental period of the structure out of dangerous resonance range and concentration of the deformation demand at the isolation system. An analytical study on the Reinforced Concrete (RC) hotel building with and without rubber bearing (RB) base isolation is carried out using the response spectrum and time history analysis methods. The results show that internal forces and inter-story drift of the building with high damping rubber bearing (HDRB) are lower than that of the fixed base with a remarkable margin. From this study, it is recommended to use the HDRB base isolation for medium and high rise buildings with soft soil in Padang City, Indonesia.

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Fully predictive Common Rail fuel injection apparatus model and its application to global system dynamics analyses

International Journal of Engine Research ◽

10.1177/1468087416653246 ◽

2016 ◽

Vol 18 (3) ◽

pp. 273-290 ◽

Cited By ~ 5

Author(s):

Alessandro Ferrari ◽

Pietro Pizzo

Keyword(s):

High Pressure ◽

Control System ◽

Fuel Injection ◽

Time History ◽

Pressure Control ◽

Rail Pressure ◽

High Pressure Pump ◽

Pressure Time ◽

Pressure Control System ◽

Injection Apparatus

A fully predictive model of a Common Rail fuel injection apparatus, which includes a detailed simulation of rail, pump, piping system, injectors and rail pressure control system, is presented and discussed. The high-pressure pump and injector sub-models have been validated separately and then coupled to the rail and pressure control system sub-models. The complete predictive model has been validated and applied to investigate the effects of the dynamics of each component of the injection apparatus on the rail pressure time history. Variable timing of the high-pressure pump delivery phases has also been considered, and the influence of this parameter on the injection performance has been analysed for both single- and multiple-injection events. Furthermore, the injection system dynamics during the transients between steady-state working conditions has been investigated in order to highlight the role played by the dynamic response of the pressure control system on the rail pressure time history.

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