Shearing stress of wheat stalk was measured for four moisture content levels (15, 25, 35 and 45%, w.b.), three cutting heights (100, 200 and 300 mm), two types of cutting knives, smooth and serrated edge and three blades oblique angle (0, 15 and 30 deg.). The results of data analysis showed that the shearing stress of wheat stems decreased as the moisture content decreased. The shearing force o...

tehran shomal highway passes through alborz mountains with a tunnel length of 6400 meters. there are two main tunnels. a full three-dimensional (3d) numerical analysis coupled with elasto-plastic material models was conducted on the inclined access tunnel. bending moment, axial force and the lining displacements due to the internal forces applied on the shotcrete lining are calculated. axial fo...

A field-driven bending method is introduced in this paper according to the coordinate transformation between straight and curved coordinates. This novel method can incorporate with the periodic boundary conditions in analysis along axial, bending, and transverse directions. For the case of small bending, the bending strain can be compatible with the beam theory. Consequently, it can be regarded...

many researchers have been efforted to identify the shape of distribution of stress and strength of castellated beam and base on that, offer a method for design that members. through this methods, comparing virendil method by simplicity and reasonable results, have been used widly. regardless from shortcoming of this method, there is two idea for distribution of stresses via primary bending in ...

Bending is one of the most common metal forming technology and it can be applied not only in sheet metal forming but also in forming of wires, rods, strips, pipes and bars. However, in car production, ship building and home appliance manufacturing sheet metal bending is most widely employed. One of the most significant sheet metal bending operations is V – Die bending. This process consists of ...

AIM To develop analytical models and analyse the stress distribution and flexibility of nickel-titanium (NiTi) instruments subject to bending forces. METHODOLOGY The analytical method was used to analyse the behaviours of NiTi instruments under bending forces. Two NiTi instruments (RaCe and Mani NRT) with different cross-sections and geometries were considered. Analytical results were derived...

We demonstrate, by theoretical analysis and molecular dynamics simulation, a mechanism for fabricating nanotubes by self-bending of nanofilms under intrinsic surface-stress imbalance due to surface reconstruction. A freestanding Si nanofilm may spontaneously bend itself into a nanotube without external stress load, and a bilayer SiGe nanofilm may bend into a nanotube with Ge as the inner layer,...

Wafer made from single crystal gallium arsenide (GaAs) are used as substrate materials in microand opto-electronic devices. During the various processes of manufacturing, the wafers are subjected to mechanical loads which may lead to fracture. The characterization of the fracture strength of the wafers need bending tests and a theoretical calculation of various stress distributions within the w...

Distributions of growth strains in branches, straight trunks and basal sweeping trunks of Chamaecyparis formosensis Matsum. trees were measured with strain gauges. Microfibril angles (MFAs) of the S2 layer of the cell wall were measured by the iodine deposition method and their relationships with growth strain examined. The magnitude of the compressive stress on the lower side of trunks with a ...