Authors: Pietro Giovanni Luccarelli, Stefano Foletti, Garrett Pataky, Huseyin Sehitoglu
Abstract: The behavior of a Ni-based superalloy, Haynes 230, was investigated at macro and micro scale level by means of a Crystal Plasticity (CP) model implemented in an open source Finite Element code, Warp3D. Single Crystal and polycrystalline specimens have been experimentally characterized with Digital Image Correlation (DIC) to identify the local strain field evolution. The results of single crystal’s tensile tests were used to obtain an estimation of the constitutive model parameters. Then a polycrystalline model, reproducing a tensile test with loading/unloading steps, was created starting from the microstructural data obtained with EBSD (electron back-scatter diffraction), which allowed the identification of grains geometry and orientations. The polycrystalline simulations were used to verify the prediction of the CP model over the experiment. The results of this study show that the comparison between experiments and numerical analysis is in good agreement on both global and local scale levels.
294
Authors: Zhi Hong Dong, Chang Chun Zhou
Abstract: Teeth is the most hard tissue in human body, and its component contains over 96 wt.% inorganic mineral. When the teeth were destroyed by chewing, whiten, etched and friction, etc., ceramic materials are one of the most widely used materials for dental defect repairing or replacement [1-3]. Stress distribution of teeth is necessary to evaluate due to bearing the heavier load, especially the mandibular first molar. But its structure is so complex as not to measure the stress distribution accurately. With the development of CAD/CAM technology, some new technology and equipments occurrence may supply for good methods to evaluate the characteristics of complex structures [4-7]. Since Farah introduced a finite element analysis method into the field of oral medicine in 1973, the method was widely used to research the teeth mechanics, which is most suitable and efficient tools compared with other technologies [8]. In this paper, molar stress distributions were analyzed. By three-dimensional optical scanner and computer 3D design software such as solidworks, Geomagic Studio, CATIA V5, a molar model was built with accuracy and effectiveness, further the mechanical properties of ceramics denture was achieved.
100
Authors: Ze Lin Niu, Zhan Ping Song
Abstract: The article analyzed the forced state of the surrounding rock and the tunnel lining for Fu longping double-decked tunnel by the Elasto-plastic finite element method. In the analysis, DP’s yield criterion was employed for the elasto-plastic characteristics of materials. It studied the construction method with the theory, and guided the construction for the double-decked tunnel ,too.
1511
Authors: Corina Mărcăuţeanu, Florin Topală, Meda Lavinia Negrutiu, Eniko Tunde Stoica, Cosmin Sinescu
Abstract: Abfractions are wedge-shaped cervical lesions which appear due to flexure of enamel and/or dentin at some location distant from the actual point of loading. The tensions may reach the fatigue limit and lead to rupture of the amelar and dentinal materials. We used the finite element method (FEM) to investigate the effect of high occlusal forces on the dental and restorative materials placed in the cervical buccal region. We developed two 3D models of maxillary premolars in order to compare the stress profiles in the buccal cervical regions under functional (20 N) and parafunctional (800 N) occlusal loads. The discretization of the tooth morphology resulted in 18889 elements and 31425 nodes. The models was subjected to occlusal analysis. The equivalent tensions (Pa) found in the buccal cervical region of the premolars at the application of parafunctional occlusal loads (800 N) are high enough to induce the breakdown of dentinal and compomer materials (over 2.41E+08 Pa). Cervical stresses induced by masticatory forces (20 N) have much lower values, which are not harmful for the dental materials. In conclusion, occlusal overload can cause damage to both the dentinal and compomer restorative materials placed in the cervical buccal region of teeth.
82
Authors: Bin Zheng, Yong Qi Liu, Rui Xiang Liu, Jian Meng
Abstract: In this paper, with the ANSYS, stress distribution, safety factor and fatigue life cycle of high-pressure common rail diesel engine connecting rod were analyzed by using 3D finite element method. The results show that the position of maximum principal stress is transition location of small end and connecting rod shank at maximum compression condition. The value of stress is 253.98 MPa in dangerous position. Safety factor is 2.67. The position of maximum principal stress is medial surface of small end at maximum stretch condition. The value of stress is 87.199 MPa in dangerous position. The fatigue life cycle of connecting rod is 2.6812×108. Fatigue safety factor is 1.5264.
531
Authors: Bin Zheng, Yong Qi Liu, Rui Xiang Liu, Jian Meng
Abstract: In this paper, with the ANSYS, stress distribution and safety factor of stationary power generation diesel engine connecting rod were analyzed by using 3D finite element method. The results show that the position of maximum principal stress is transition location of small end and connecting rod shank at maximum compression condition. The value of stress is 176 MPa in dangerous position. Maximum deformation is 0.0713mm. Safety factor is 1.86. The oil-hole of small end is the exposed destructive positions at maximum stretch condition. Maximum stress value is 67.7 MPa in dangerous position. Maximum deformation is 0.0145mm.
1992
Authors: Bin Zheng, Yong Qi Liu, Rui Xiang Liu, Jian Meng
Abstract: In this paper, with the ANSYS, stress distribution and safety factor of marine diesel engine connecting rod were analyzed by using 3D finite element method. The results show that the position of maximum principal stress is transition location of small end and connecting rod shank at maximum stretch condition. The value of stress is 24.69 MPa in dangerous position. The position of maximum principal stress is transition location of small end and connecting rod shank at maximum stretch condition. The value of stress is 198.65 MPa in dangerous position. Safety factor is 2.51.
351
Authors: Yue Zhang, Mi Zhou
Abstract: South pile foundation of Ma On Shan Yangtze River Highway Bridge is big, deep, soft soil, groundwater rich. In order to guarantee the safeties of the foundation, its foundation pit supporting schemes are compared, selected and calculated, finally lock mouth steel pipe support is selected as the design and construction scheme. The three-dimensional simulation analysis of the scheme is calculated by using MIDAS software, simulated four construction condition is presented, and stress and deformation results of retaining structure on various operating conditions is obtained. The calculation results show that the palisade structure basic satisfies the requirements of caps excavation and caps concrete construction. The results of construction show that the construction method, model and parameters used in this paper are basic right, the reasonableness of Supporting is confirmed and for the similar large foundation pit construction provides useful reference.
4207
Abstract: Self-pierce riveting (SPR) technology offers an alternative to resistance spot welding (RSW) for joining sheet materials. It has been found that the SPR technology produced a much stronger joint than the RSW in fatigue test. For efficient design of SPR structures, the knowledge of dynamic characteristics of the SPR beams is essential. In this paper, the free transverse vibration characteristics of single lap-jointed cantilevered SPR beams are investigated in detail. The focus of the analysis is to reveal the influence on the natural frequency and natural frequency ratio of these beams caused by variations in the material properties of sheet materials to be jointed. It is shown that the transverse natural frequencies of single lap jointed cantilevered SPR beams increase significantly as the Young’s modulus of the sheet materials increases, but change slightly corresponding to the change in Poisson’s ratio. It is also found that the material density of the sheets have significant effects on the free transverse vibration characteristics of the beams.
999
Authors: Qing Fen Li, Li Zhu, Friedrich G. Buchholz, Sheng Yuan Yan
Abstract: Some results of 3D finite element analyses of the all fracture modes (AFM) specimen on mixed-mode II and III fracture are presented in this paper. The computational fracture analysis is based on the calculation of separated strain energy release rates (SERRs) along the crack front by the modified virtual crack closure integral (MVCCI)-method and the commercially available FE-code ANSYS. Calculation results show that under pure in-plane shear loading (mode II), not only the mode II, but also the mode III loading conditions, are generated owing to the Poission’s ratio effects. Similarly, under pure out-of-plane shear loading (mode III), besides the mode III, the mode II loading conditions are induced due to the global deformation. Nevertheless, once in-plane and out-of-plane shear loadings are superimposed, the fracture behavior appears more complex. Further discussion is given associate with some previous study.
173