Optimizing material strength constants numerically extracted from taylor impact data

1997 ◽  
Vol 37 (3) ◽  
pp. 333-338 ◽  
Author(s):  
D. J. Allen ◽  
W. K. Rule ◽  
S. E. Jones
Keyword(s):  
Material Strength ◽  
Taylor Impact ◽  
Impact Data

A Rate-Dependent Interpretation of the Taylor Impact Test

1989 ◽  
Vol 111 (4) ◽  
pp. 254-257
Author(s):  
S. E. Jones ◽  
P. P. Gillis ◽  
J. C. Foster ◽  
L. L. Wilson
Keyword(s):  
Yield Strength ◽  
Impact Velocity ◽  
Constitutive Relations ◽  
Material Constant ◽  
Constitutive Law ◽  
Material Strength ◽  
Rate Dependent ◽  
Post Test ◽  
Static Yield ◽  
Taylor Impact

A new one-dimensional theory for estimating the dynamic yield strength of materials, based on post-test measurements of Taylor impact specimens, has been developed by the authors. This theory offers the advantage of mathematical simplicity, while requiring only measurements of final specimen length, final undeformed length, and impact velocity as experimental data inputs. It is observed that the theory can accommodate a variety of material constitutive relations while preserving its basic simplicity. In particular, the dynamic material strength on impact, Y, can be directly correlated with impact velocity V through the relation Y = − Y0 − BV2. Here Y0 is the static yield strength and B is a material constant. This relation provides a rate-dependent constitutive law that is potentially useful in situations such as rod penetration, for example.

Symmetrical Taylor impact studies of copper

2008 ◽  
Vol 465 (2103) ◽  
pp. 769-790 ◽  
Author(s):  
L.C Forde ◽  
W.G Proud ◽  
S.M Walley
Keyword(s):  
High Speed ◽  
Material Model ◽  
Material Strength ◽  
High Speed Photography ◽  
Cavendish Laboratory ◽  
Gas Gun ◽  
Framing Rate ◽  
Taylor Impact ◽  
Target Block ◽  
Annealed Copper

An integrated investigation of rod-on-rod (symmetric Taylor) impact of annealed copper was conducted using the single-stage gas-gun facility at the Cavendish Laboratory as a validation study of the Armstrong–Zerilli constitutive model, as modified by Goldthorpe. Two main techniques were used for obtaining data from the experiments: high-speed photography (up to 20 million frames s −1 framing rate) and a velocity interferometer system for any reflector (VISAR). The symmetric configuration was used to minimize friction effects and eliminate target indentation seen in classic Taylor tests, where a rod is fired against a massive target block. However, the need for coaxial alignment of the two rods made the experiments considerably more challenging to perform than the classic case. The propagation of plasticity along the rods was monitored using high-speed photography and VISAR. It was found to propagate with a logarithmically decelerating velocity. The rod profiles and VISAR traces can be understood in terms of material properties such as strain hardening. No asymmetry between the responses of the two rods involved (moving and stationary) was observed within the resolution of the techniques employed. A modified Armstrong–Zerilli material model for copper predicted intermediate profiles well, but slightly overestimated the material strength.

On the migration of smooth particle hydrodynamic formulation in Cartesian coordinates to the axisymmetric formulation

2011 ◽  
Vol 46 (8) ◽  
pp. 879-886 ◽  
Author(s):  
M Lee ◽  
Y J Cho
Keyword(s):  
High Speed ◽  
Smooth Particle Hydrodynamic ◽  
Rigid Wall ◽  
Sensitivity Study ◽  
Material Strength ◽  
Sph Method ◽  
Simple Modification ◽  
Cartesian Coordinates ◽  
Taylor Impact ◽  
Good Agreement

The smooth particle hydrodynamic (SPH) method has been extended for application to large deformation problems such as high velocity impacts by including the effect of material strength. This paper presents a simple modification of the kernel function that allows the SPH formulation in Cartesian coordinates to be migrated into an axisymmetric formulation. The proposed procedure is first applied to analyse transient deformations of a cylindrical rod impacting a rigid wall (Taylor impact test). A good agreement with published experimental data for the deformed shape is obtained. A sensitivity study of the key parameters required in the SPH formulation is conducted to provide better insight into the SPH modelling approach. Impacts between two bodies at high speed have also been simulated using an axisymmetric SPH code.

Bayesian calibration of strength model parameters from Taylor impact data

2021 ◽  
pp. 110999
Author(s):  
David Rivera ◽  
Jason Bernstein ◽  
Kathleen Schmidt ◽  
Amanda Muyskens ◽  
Matthew Nelms ◽  
...  
Keyword(s):  
Model Parameters ◽  
Strength Model ◽  
Bayesian Calibration ◽  
Taylor Impact ◽  
Impact Data

A Direct Correlation of Strength With Impact Velocity in the Taylor Test

1989 ◽  
Vol 111 (3) ◽  
pp. 327-330 ◽  
Author(s):  
P. P. Gillis ◽  
S. E. Jones
Keyword(s):  
Impact Velocity ◽  
Impact Test ◽  
Constitutive Law ◽  
Material Strength ◽  
Post Mortem ◽  
Specimen Length ◽  
Rate Dependent ◽  
Taylor Test ◽  
Undeformed Specimen ◽  
Taylor Impact

This paper presents a method for analyzing the results of a Taylor impact test. From post-mortem measurements of final specimen length and final undeformed specimen length the dynamic material strength on impact, σo, is correlated with impact velocity, V, through the relation σo=−Y−BV2 where Y and B are presumed to be material constants. This relation provides a rate-dependent constitutive law that is potentially useful in situations such as rod penetration, for example.

Analisis Daya Dukung Tanah Dan Bahan Pondasi Tiang Pancang Pada Pembangunan Jembatan Kab. Jombang

2020 ◽  
Vol 9 (1) ◽  
pp. 32-37
Author(s):  
Ruslan Hidayat ◽  
Saiful Arfaah
Keyword(s):  
Carrying Capacity ◽  
Pile Foundation ◽  
Heavy Traffic ◽  
Traffic Volume ◽  
Material Strength ◽  
Cone Penetrometer ◽  
The Village

One of the most important factors in the structure of the pile foundation in the construction of the bridge is the carrying capacity of the soil so as not to collapse. Construction of a bridge in the village of Klitik in Jombang Regency to be built due to heavy traffic volume. The foundation plan to be used is a pile foundation with a diameter of 50 cm, the problem is what is the value of carrying capacity of soil and material. The equipment used is the Dutch Cone Penetrometer with a capacity of 2.50 tons with an Adhesion Jacket Cone. The detailed specifications of this sondir are as follows: Area conus 10 cm², piston area 10 cm², coat area 100 cm², as for the results obtained The carrying capacity of the soil is 60.00 tons for a diameter of 30 cm, 81,667 tons for a diameter of 35 cm, 106,667 tons for a diameter of 40 cm, 150,000 tons for a diameter of 50 cm for material strength of 54,00 tons for a diameter of 30 cm, 73,500 tons for a diameter of 35 cm, 96,00 tons for a diameter of 40 cm, 166,666 tons for a diameter of 50 cm

Design of Pipeline Composite Repairs: From Lab Scale Tests to FEA and Full Scale Testing

2014 ◽  
Author(s):  
Remy Her ◽  
Jacques Renard ◽  
Vincent Gaffard ◽  
Yves Favry ◽  
Paul Wiet
Keyword(s):  
Finite Element ◽  
Full Scale ◽  
Combined Loading ◽  
Material Strength ◽  
Repair System ◽  
Loading Conditions ◽  
Original Design ◽  
Composite Repair ◽  
Repair Systems ◽  
Composite Properties

Composite repair systems are used for many years to restore locally the pipe strength where it has been affected by damage such as wall thickness reduction due to corrosion, dent, lamination or cracks. Composite repair systems are commonly qualified, designed and installed according to ASME PCC2 code or ISO 24817 standard requirements. In both of these codes, the Maximum Allowable Working Pressure (MAWP) of the damaged section must be determined to design the composite repair. To do so, codes such as ASME B31G for example for corrosion, are used. The composite repair systems is designed to “bridge the gap” between the MAWP of the damaged pipe and the original design pressure. The main weakness of available approaches is their applicability to combined loading conditions and various types of defects. The objective of this work is to set-up a “universal” methodology to design the composite repair by finite element calculations with directly taking into consideration the loading conditions and the influence of the defect on pipe strength (whatever its geometry and type). First a program of mechanical tests is defined to allow determining all the composite properties necessary to run the finite elements calculations. It consists in compression and tensile tests in various directions to account for the composite anisotropy and of Arcan tests to determine steel to composite interface behaviors in tension and shear. In parallel, a full scale burst test is performed on a repaired pipe section where a local wall thinning is previously machined. For this test, the composite repair was designed according to ISO 24817. Then, a finite element model integrating damaged pipe and composite repair system is built. It allowed simulating the test, comparing the results with experiments and validating damage models implemented to capture the various possible types of failures. In addition, sensitivity analysis considering composite properties variations evidenced by experiments are run. The composite behavior considered in this study is not time dependent. No degradation of the composite material strength due to ageing is taking into account. The roadmap for the next steps of this work is to clearly identify the ageing mechanisms, to perform tests in relevant conditions and to introduce ageing effects in the design process (and in particular in the composite constitutive laws).

Sign in / Sign up

Export Citation Format

Share Document