Experimental testing and 3D meso-scale numerical simulations of SCC subjected to high compression strain rates

Theoretical, numerical and experimental studies were conducted on the axial crushing behavior of traditional single-cell and innovative four-cell extrusions. Two commercial aluminum alloys, 6061 and 6063, both with two tempers (T4 and T6), were considered in the study. Testing coupons taken from the extrusions assessed the nonlinear material properties. A theoretical solution was available for the one-cell design, and was developed for the mean crushing force of the four-cell section. Numerical simulations were carried out using the explicit finite element code LS-DYNA. The aluminum alloy 6063T4 was found to absorb less energy than 6061T4, for both the one-cell and four-cell configurations. Both 6061 and 6063 in the T6 temper were found to have significant fracture in the experimental testing. Theoretical analysis and numerical simulations predicted a greater number of folds for the four-cell design, as compared to the one-cell design, and this was confirmed in the experiments. The theoretical improvement in energy absorption of 57% for the four-cell in comparison with the one-cell design was confirmed by experiment. The good agreement between the theoretical, numerical and experimental results allows confidence in the application of the theoretical and numerical tools for both single-cell and innovative four-cell extrusions. It was also demonstrated that these materials have very little dynamic strain rate effect.

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Dynamic Response of a Road Bridge Subjected to Passing a Heavy Vehicle over a Standard Irregularity - Numerical Modelling and Experimental Testing

Communications - Scientific letters of the University of Zilina ◽

10.26552/com.c.2022.1.d37-d45 ◽

2022 ◽

Vol 24 (1) ◽

pp. D37-D45

Author(s):

Milan Moravčík

Keyword(s):

Numerical Modelling ◽

Dynamic Response ◽

Numerical Simulations ◽

Experimental Testing ◽

Heavy Vehicle ◽

Dynamic Effects ◽

Actual Problem ◽

Box Girder ◽

Dynamic Excitation ◽

Girder Bridge

The paper presents an analysis of an actual problem related to dynamic effects to road bridges due to travelling a heavy vehicle over the bridge. Numerical simulations of the dynamic response are applied on a fictitious simple beam of the length Lb = 52 m with an artificial irregularity at midspan, corresponding to a characteristic span L (b5) = 52 m of the ten-span continuous box girder bridge. A heavy four-axle truck m v = 32 t is used for dynamic excitation, travelling over the bridge at passing speed of 70km / h. The obtained results are compared to results of the experimentally tested ten-span continuous pre-stressed reinforced concrete girder bridge at the same speed.

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Experimental Observations and Numerical Simulations of Wave Impact Forces on Recurved Parapets Mounted Above a Vertical Wall

Volume 2: Structures, Safety and Reliability ◽

10.1115/omae2009-79183 ◽

2009 ◽

Author(s):

David Newborn ◽

Nels Sultan ◽

Pierre Beynet ◽

Tim Maddux ◽

Sungwon Shin ◽

...

Keyword(s):

Numerical Model ◽

Numerical Simulations ◽

Shear Force ◽

Experimental Testing ◽

Vertical Wall ◽

Experimental Tests ◽

Vertical Force ◽

Base Shear ◽

Wave Impact ◽

Overturning Moment

Large-scale hydraulic model tests and detail numerical model investigations were conducted on recurved wave deflecting structures to aid in the design of wave overtopping mitigation for vertical walls in shallow water. The incident wave and storm surge conditions were characteristic return period events for an offshore island on the North Slope of Alaska. During large storm events, despite depth-limited wave heights, a proposed vertical wall extension was susceptible to wave overtopping, which could potentially cause damage to equipment. Numeric calculations were conducted prior to the experimental tests and were used to establish the relative effectiveness of several recurved parapet concepts. The numerical simulations utilized the COrnell BReaking waves and Structures (COBRAS) fluid modeling program, which is a Volume-of-Fluid (VOF) model based on Reynolds Averaged Navier-Stokes equations [1] [2]. The experimental testing was conducted in the Large Wave Flume (LWF) at Oregon State University, O.H. Hinsdale Wave Research Laboratory. The experimental test directly measured the base shear force, vertical force, and overturning moment applied to the recurved parapets due to wave forcing. Wave impact pressure on the parapet and water particle velocities seaward of the wall were also measured. Results from the experimental testing include probability of exceedance curves for the base shear force, vertical force, and overturning moment for each storm condition. Qualitative comparisons between the experimental tests and the COBRAS simulations show that the numerical model provides realistic flow on and over the parapet.

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Determining the impact behavior of concrete beams through experimental testing and meso-scale simulation: II. Particle element simulation and comparison

Engineering Fracture Mechanics ◽

10.1016/j.engfracmech.2014.12.020 ◽

2015 ◽

Vol 135 ◽

pp. 113-125 ◽

Cited By ~ 6

Author(s):

Mingxin Wu ◽

Chuhan Zhang ◽

Zhenfu Chen

Keyword(s):

Concrete Beams ◽

Experimental Testing ◽

Impact Behavior ◽

Element Simulation ◽

The Impact ◽

Meso Scale

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A Numerical Study on Ductile Material Failure

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.324-325.483 ◽

2006 ◽

Vol 324-325 ◽

pp. 483-486

Author(s):

K. Qin ◽

Li Ming Yang

Keyword(s):

Numerical Simulations ◽

Numerical Study ◽

Hydrostatic Stress ◽

Element Model ◽

Ductile Material ◽

Dominant Factor ◽

Strain Rates ◽

Ductile Materials ◽

Relative Spacing ◽

The Relationship

Experiments show that the failure of ductile materials can be characterized by a rate-independent parameter, relative spacing d defined as the ratio of the distance between two voids and the radius of voids. In this study, this experimental phenomenon is analyzed via numerical simulations using 3-D finite element model. Considering that hydrostatic stress is a dominant factor in the evolution of microvoid nucleation, growth and coalescence in ductile materials, numerical simulations are performed to obtain the relationship between relative spacing d and hydrostatic stress in the ligament between voids. Numerical results show that hydrostatic stress along matrix ligament is sensitive to the change of the relative spacing. Further analysis shows that the failure of ductile materials can modeled by using a criterion of the threshold of local hydrostatic stress in the ligament. Based on such a criterion, a curve displaying the relationship between the strength of ductile material and strain rate is obtained numerically. It is concluded that the failure criterion of ductile materials can be described by using local hydrostatic stress and relative spacing between two voids, which is not sensitive to strain rates.

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Strength Characterization of Soils’ Properties at High Strain Rates Using the Hopkinson Technique—A Review of Experimental Testing

Materials ◽

10.3390/ma15010274 ◽

2021 ◽

Vol 15 (1) ◽

pp. 274

Author(s):

Kamil Sobczyk ◽

Ryszard Chmielewski ◽

Leopold Kruszka ◽

Ryszard Rekucki

Keyword(s):

Critical Infrastructure ◽

Water Saturation ◽

Experimental Testing ◽

Cohesive Soil ◽

Grain Structure ◽

Large Field ◽

Strain Rates ◽

Soil Specimen ◽

Wide Range ◽

Heated Soil

The paper presents a review of crucial experiments and the latest publications, presenting the previous and current trends in experimental research in 2018–2021 in the area of soil dynamic interaction based on the Hopkinson bar technique. A review of investigated experimental test stands was made, in particular, cohesive and non-cohesive soil specimens prepared with different dimensions and densities. From this study, it can be concluded that the dynamic response of the soil depends on many factors, e.g., density, cohesion, moisture and grain structure of the soil specimen. There is still a noticeable interest in SHPB experiments performed in both 1D and 3D versions under modified conditions (frozen/heated soil specimen, different degree of water saturation content of the soil sample) in a wide range of strain rates 102–104 s−1, which is a large field for further research. The need to learn about the characteristics of various types of soil (both cohesive and non-cohesive) for the selection of structural design solutions for the protection elements of critical infrastructure was emphasized.

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Experimental and Numerical Investigation into Failure Modes of Tension Angle Members Connected by One Leg

Materials ◽

10.3390/ma14185141 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5141

Author(s):

Edyta Bernatowska ◽

Lucjan Ślęczka

Keyword(s):

Numerical Simulations ◽

Failure Mode ◽

Failure Modes ◽

Experimental Testing ◽

Load Capacity ◽

Strength Function ◽

Experimental Tests ◽

Material Model ◽

Design Standards ◽

Element Analysis

This paper presents the results of experimental and numerical tests on angle members connected by one leg with a single row of bolts. This study was designed to determine which failure mode governs the resistance of such joints: net section rupture or block tearing rupture. Experimental tests were insufficient to completely identify the failure modes, and it was necessary to conduct numerical simulations. Finite element analysis of steel element resistance based on rupture required advanced material modelling, taking into account ductile initiation and propagation of fractures. This was realised using the Gurson–Tvergaard–Needleman porous material model, which allows for analysis of the joint across the full scope of its behaviour, from unloaded state to failure. Through experimental testing and numerical simulations, both failure mechanisms (net section and block tearing) were examined, and an approach to identify the failure mode was proposed. The obtained results provided experimental and numerical evidence to validate the strength function used in design standards. Finally, the obtained results of the load capacity were compared with the design procedures given in the Eurocode 3′s current and 2021 proposed editions.

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A hydro-pneumatic machine for intermediate strain-rates: Set-up, tests and numerical simulations

DYMAT 2009 - 9th International Conferences on the Mechanical and Physical Behaviour of Materials under Dynamic Loading ◽

10.1051/dymat/2009054 ◽

2009 ◽

Cited By ~ 1

Author(s):

V. Tarigopula ◽

C. Albertini ◽

M. Langseth ◽

O. S. Hopperstad ◽

A. H. Clausen

Keyword(s):

Numerical Simulations ◽

Strain Rates ◽

Intermediate Strain Rates ◽

Set Up

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Experimental Testing and Numerical Simulations of Shrouded Plug-Nozzle Flowfields

Journal of Propulsion and Power ◽

10.2514/1.b34237 ◽

2012 ◽

Vol 28 (3) ◽

pp. 530-544 ◽

Cited By ~ 4

Author(s):

Dheeraj S. K. Kapilavai ◽

John Tapee ◽

John Sullivan ◽

Charles L. Merkle ◽

Thomas R. Wayman ◽

...

Keyword(s):

Numerical Simulations ◽

Experimental Testing ◽

Plug Nozzle

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Fracture Initiation in Notched Specimens Subjected to Compression: Strain Rate Effect

Materials ◽

10.3390/ma13112613 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2613

Author(s):

Elżbieta Bura ◽

Andrzej Seweryn

Keyword(s):

Strain Rate ◽

High Speed ◽

Fracture Process ◽

Fracture Initiation ◽

Strain Rate Effect ◽

Rate Effect ◽

Specimen Thickness ◽

Strain Rates ◽

Notched Specimens ◽

Compression Strain

This paper shows the results of an experimental investigation on fracture in polymethyl methacrylate (PMMA) notched specimens subjected to compression (with unloading) including different strain rates. Three types of notches were used. Flat specimens were weakened by two types of V-notches and U-notches. Additionally, two specimen thicknesses were used (9.7 and 14.5 mm). The load was carried out at the strain rate of 8 × 10−4, 4 × 10−3, and 2 × 10−2 s−1 and the unloading stage was conducted ten times faster, i.e., 8 × 10−3, 4 × 10−2, and 2 × 10−1 s−1, respectively. By using a PHANTOM high-speed camera, fracture initiation moments and locations were indicated. Two types of crack were observed and distinguished as A-type and B-type. The first was formed by the contact stress of the closing notch surfaces, while the latter was formed by the residual stresses during the unloading stage. The type of notch, specimen thickness, and the strain rate have a significant influence on the fracture process. The strain rate has a large impact on the critical load value, which determines the fracture initiation, but does not affect the location and shape of the crack. The strain rate effect usually disappears with increasing specimen thickness.

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