Extended overstress model and its implicit stress integration algorithm: Formulations, experiments and simulations

2021 ◽  
Author(s):  
Takuya Anjiki ◽  
Koichi Hashiguchi
Keyword(s):  
Integration Algorithm ◽  
Stress Integration

An inelastic stress integration algorithm for a rock mass containing sets of discontinuities

2012 ◽  
Vol 8 (3) ◽  
pp. 265-278 ◽  
Author(s):  
Nenad Grujovic ◽  
Dejan Divac ◽  
Miroslav Zivkovic ◽  
Radovan Slavkovic ◽  
Nikola Milivojevic ◽  
...  
Keyword(s):  
Rock Mass ◽  
Integration Algorithm ◽  
Stress Integration

scholarly journals Computational algorithm for the verification of reinforced concrete sections in fire situation

2019 ◽  
Vol 12 (4) ◽  
pp. 932-955
Author(s):  
E. P. G. PADRE ◽  
J. C. L. RIBEIRO ◽  
R. C. S. S. ALVARENGA ◽  
R. C. SILVA
Keyword(s):  
Reinforced Concrete ◽  
Structural Design ◽  
Room Temperature ◽  
Computational Algorithm ◽  
Technical Standards ◽  
Technical Literature ◽  
Element Mesh ◽  
Integration Algorithm ◽  
Stress Integration ◽  
In Fire

Abstract Reinforced concrete structures may have reduced strength due to the degradation of their mechanical properties by temperature. This can increase the risk of structural collapses. Thus, the structural design should consider its behavior at room temperature and in fire situation (ABNT NBR 14432:2001). This study presents the development of an algorithm to verify the strength of any reinforced concrete sections subjected to unsymmetrical bending at room temperature and in fire situation. For this purpose, a stress integration algorithm was implemented from the strain profile of the section according to ABNT NBR 15200:2012, linked to a finite element mesh generator and a thermal analysis algorithm. For validation of the developed program, called Pisafo, the results obtained were compared with those in the technical literature: obtained in experiments (with differences of up to 28.5%) and with recognized software solutions (with differences of up to -14.8%). The largest variations in relation to the experiments can be attributed to the differences between the thermal properties of the concrete in the experiments with those prescribed in the technical standards used by the program and the non-consideration of spalling in the computational analysis.

A STUDY ON EXPERIMENTS AND SIMULATIONS FOR DUCTILE FRACTURE OF ISOTROPIC MATERIAL USING ROUSSELIER'S DAMAGE MODEL

2012 ◽  
Vol 06 ◽  
pp. 257-262
Author(s):  
Junhang Guo ◽  
Ri-ichi Murakami ◽  
Shengdun Zhao
Keyword(s):  
Ductile Fracture ◽  
Damage Mechanics ◽  
Volume Fraction ◽  
Damage Model ◽  
Void Volume Fraction ◽  
Void Volume ◽  
Integration Algorithm ◽  
Stress Integration ◽  
Simulation Results ◽  
Critical Void

Ductile fracture has been a hot topic for a long time for its importance to mechanical design in evaluating the risk of failure. In this paper, the A5052BD-H14's ductile fracture is studied using a new constitutive equation based on the continuum damage mechanics. A novel full-implicit stress integration algorithm is developed based on Rousselier's damage model and implemented into finite element analysis (FEA) models by the ABAQUS/Explicit using the user material subroutine. The tensile tests of A5052BD-H14 with notch were taken and the load-displacement curves were recorded. By simulations, the evolutions of the void volume fraction are obtained and can be used as calibration for the critical void volume fraction. The validity of the damage model and the proposed stress integration algorithm are verified by comparing the experimental results and the simulation results. Further, by using the critical void volume fraction and element deletion, the simulation results show that this method is reliable, and can be used to predict the fracture of metals.

Enhanced Detection Sensitivity with Pulsed Laser Digital Signal Integration Algorithm

2006 ◽  
Author(s):  
A.C.T. Quah ◽  
J.C.H. Phang ◽  
L.S. Koh ◽  
S.H. Tan ◽  
C.M. Chua
Keyword(s):  
Fault Localization ◽  
Pulsed Laser ◽  
Digital Signal ◽  
Detection Sensitivity ◽  
Signal Integration ◽  
Laser Operation ◽  
Frequency Range ◽  
Integration Algorithm ◽  
Detection Systems ◽  
Lock In

Abstract This paper describes a pulsed laser induced digital signal integration algorithm for pulsed laser operation that is compatible with existing ac-coupled and dc-coupled detection systems for fault localization. This algorithm enhances laser induced detection sensitivity without a lock-in amplifier. The best detection sensitivity is achieved at a pulsing frequency range between 500 Hz to 1.5 kHz. Within this frequency range, the algorithm is capable of achieving more than 9 times enhancement in detection sensitivity.

Sign in / Sign up

Export Citation Format

Share Document