latticed columns are frequently used in industrial steel structures. in some countries these built-up columns might be even used in other types of steel structures such as residential and commercial buildings. besides, latticed columns are parts of skeletons of many historic buildings all around the world. to analyze a steel structure with latticed columns a more accurate numerical model for su...

objective: the main goal of this study was to evaluate stress distribution of endodonti-cally treated maxillary central incisors restored with glass fiber posts, composite resin cores, and crowns with different ferrule designs. materials and methods: four three-dimensional models of a maxillary central incisor were modeled in solidworks 2006. tooth with no ferrule, tooth with a 2 mm circumferen...

o bjectives: headgears are among the effective orthodontic appliances to achieve treatment goals. unilateral molar distal movement is sometimes needed during an orthodontic treat- ment, which can be achieved by an asymmetric headgear. different unilateral headgears have been introduced. the main goal of this study was to analyze the force system of uni- lateral expanded outer bow asymmetric hea...

This paper deals with the modeling of punching shear failure in reinforced concrete slabs using nonlinear finite element analysis. The 3D finite element analyses (FEA) were performed with the appropriate modeling of element size and mesh, and the constitutive modeling of concrete. The FE numerical models are validated by comparing with the experimental results obtained from tested specimens and...

this study aims to numerically investigate on the crashworthiness of thin-walled square tubes by consideration of 3-d oblique loading. in this type of loading, direction of loading is defined by using two spatial angles relative to the position of the tube. to this aim, finite element (fe) analysis is employed to simulate the loading for 8 different numerical models with different loading orien...

several appliances have been used for palatal expansion for treatment of posterior cross bite. the purpose of this study was to evaluate the stress induced in the apical and crestal alveolar bone and the pattern of tooth displacement following expansion via removable expansion plates or fixed-banded palatal expander using the finite element method (fem) analysis.two 3d fem models were designed ...

o bjectives: this study sought to assess distal and lateral forces and moments of asymmetric headgears by variable outer bow lengths. materials and methods : four 3d finite element method (fem) models of a cer- vical headgear attached to the maxillary first molars were designed in solidworks2010 software and transferred to ansys workbench ver. 11 software. modelscontained the first molars, thei...

objective: intrusion as a type of tooth movement is managed by different mechanotherapies during various treatment stages. the morphology of the apical third of the teeth to be intruded plays an important role in the risk of root resorption due to the raise of stresses. the main goal of this study was to compare various types of apical third of the teeth while loaded by an intrusive force. mate...

Many researchers content themselves with the 2D simulation of welding process instead of the 3D simulation, because of the time and the cost factors of the latter. In this research, the number of elements and nodes are reduced by an initiative plan (defining an equivalent model) for the simulation of welding. The welding process has been simulated by an uncoupled thermal-mechanical finite eleme...

Introduction: the Restoration of endodontically treated teeth is critical, and the Awareness of stresses developed by oblique and vertical forces in restorative methods take a great role in treatment plans. Due to the anatomical shape and inherent form of the stress distribution premolars, could be lost by fractures. Some fractures such as vertical fracture which is probable in...