The paper describes a computer analysis of the pull-out test used to determine force needed pull out fragment rock and shape this broken fragment. analyzed material is sandstone porphyry. included comparison different methods propagation cracks in Abaqus program using Finite Element Method. work also contains description laboratory tests analytical considerations.

This paper describes a method of predicting the direction crack propagation implemented by user subroutines in Simulia-Abaqus FEA system with use extended finite element (X-FEM). is based on displacements and stresses according to Westergaard’s solution Griffith’s problem. During calculations, each increment, algorithm reads model around tip, calculates criterion values at read points, reduces them unit distance from fits polynomial these finds minimum function closest last angle. The also...

Abstract The article describes a computer analysis of the pull-out test used to calculate force needed pull out rock fragment and determine shape this broken fragment. analyzed material is sandstone porphyry. included first approach using own subroutine in Simulia Abaqus system, that is, which task undertaken accurately crack path Finite Element Method model. work also contains description laboratory tests analytical considerations.

This paper describes the computer analysis of pull-out test for determining force needed to pull out a rock fragment and shape this fractured fragment. The material analyzed is sandstone. Two tasks were depending on length pulling anchor. also included comparison various crack propagation methods in programs using Finite Element Method. It planned perform laboratory tests verify accuracy selected methods.

The paper presents the analysis of Brazilian compression tests considering possibilities determining proper tensile strength. These analyses include precise designation stress field without singularity at point application force, evaluation critical in light classical and contemporary failure criteria for a brittle material, determination position where destructive crack is expected to be initiated sample.

The paper presents the results of mechanical tests three types rocks from stone mines in Poland. Compression cubic samples, three-point bending beams, beams with notch and testing tensile strength using quasi-Brazilian method were performed. Based on tests, compressive strength, Young's modulus, Poisson's ratios determined. stress intensity factor critical strain energy release rate mode I determined test notched beams. values used as parameters computer models which are to verify authors’...

This paper presents the results of computer simulations fracture in three laboratory tests: three-point bending a notched beam cut from sandstone, pull-out test self-undercutting anchor fixed and bar embedded concrete. Five material failure criteria were used: Rankine, Coulomb–Mohr, Drucker–Prager, Ottosen–Podgórski, Hoek–Brown. These implemented Abaqus® FEA system to work with crack propagation modeling method—extended finite element method (X-FEM). All yielded similar force–displacement...

This paper describes the computer analysis of pull-out test for determining force needed to pull out a rock fragment, and shape this fractured fragment. The material analysed is sandstone. included comparison various crack propagation methods in program using Finite Element Method. work also contains description performed laboratory tests analytical considerations.

The paper presents the laboratory test results of mechanical properties porous gypsum. Material for study was obtained from gypsum Pro-Monta plate 100mm thick. Based on compression cubic samples, following were determined: compressive strength, Poisson's ratio and Young's modulus. Tensile strength determined based three-point bending rectangular cross section sample. Also a friction coefficients investigated as follows: between smoothed surface sample fiberboard pad, rough surfaces (after...

The paper presents the results of laboratory tests and computer simulations pull-out test a rod embedded in concrete cylindrical sample.The main purpose was to verify force-displacement relationship crack paths.The X-FEM method fracture simulation used.The authors compared simple maximum principal stress criterion, as well their own simulating propagation brittle materials, implemented with user subroutine Simulia Abaqus FEA system.A number conclusions were obtained analyzes, related...

This article presents the results of computer simulations a four-point bending test concrete single-edge notched beam. In this publication, authors compared X-FEM method simulating crack in Abaqus FEA system. The paper also contains obtained with subroutine recently developed by authors, used for defining direction and failure criterion. publication explains way working algorithm. described calculations show that analysis gives unrealistic terms destructive force. SEN-beam is an interesting...

This paper describes the results of static non-linear calculations in reference to a typical building scaffolding, case when scaffolding is operated. The influence value and localization imperfections was analyzed researches. It found that geometrical cause increase internal forces, highest occurs lowest elements. Higher normal stresses were also obtained modelled as regular horizontal displacements decks than case, they arranged according form buckling.

The paper presents the results of numerical simulation brittle material fracture initiated by Griffi th's crack situated at any angle with respect to load direction.The simulations were performed Simulia Abaqus FEA system using X-FEM method.The direction propagation was determined user's subroutine written in Fortran, implemented system.The authors programmed several conditions for propagation: maximum principal stress criterion, Ottosen-Podgórski three criteria based on displacements around...

W pracy przedstawiono wyniki badań mechanicznych dwóch rodzajów piaskowca pochodzącego z kopalń kamienia w Polsce. Wykonano badania ściskania próbek sześciennych, trójpunktowego zginania belek, belek nacięciami i badanie wytrzymałości na rozciąganie przy zginaniu oraz ściskaniu metodą kwazi-brazylijską. Na podstawie przeprowadzonych wyznaczono wartości ściskanie, rozciąganie, moduły Younga współczynniki Poissona. Z testu naciętych krytyczny mnożnik intensywności naprężeń pierwszej modzie...