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This article deals with the challenges of semi‐integral construction of long viaducts. The main characteristic of semi‐integral bridges is the monolithic connection of most parts of the substructure with the superstructure. This leads to complex load‐bearing behavior, in which several structural components interact with each other. Because of the longitudinal movement of the superstructure, constraint forces and moments occur in the piers. They induce additional stresses in the structure compared to conventionally supported bridges. An important issue during the design process is the choice of the pier cross section. The stiffness and ductility of the piers influence the constraint moments and failure behavior of the pier. This is the reason why the detailed investigation into the influencing parameters (normal‐force utilization, reinforcement ratio, and width‐to‐height ratio) described in this paper was carried out. In this investigation, the moment–curvature relationship was used and the failure behavior as well as the constraint moments in the structure were evaluated. [ABSTRACT FROM AUTHOR]

The frictional performances of surgical sutures have been found to play a vital role in their functionality. The purpose of this paper is to understand the frictional performance of multifilament surgical sutures interacting with skin substitute, by means of a penetration friction apparatus (PFA). The influence of the size of the surgical suture was investigated. The relationship between the friction force and normal force was considered, in order to evaluate the friction performance of a surgical suture penetrating a skin substitute. The friction force was measured by PFA. The normal force applied to the surgical suture was estimated based on a Hertzian contact model, a finite element model (FEM), and a uniaxial deformation model (UDM). The results indicated that the penetration friction force increased as the size of the multifilament surgical suture increased. In addition, when the normal force was predicted by UDM, it was found that the ratio between the friction force and normal force decreased as the normal force increased. A comparison of the results suggested that the UDM was appropriate in predicting the frictional behavior of surgical suturing. [ABSTRACT FROM AUTHOR]

In this paper, complex Poynting theorem is used to calculate the power transmitted from primary to other areas of single-sided linear induction motor. By the help of Poynting theorem and boundary conditions, the longitudinal end effect is completely included into the analysis. Having comprehensive information about power flow and using the coenergy method, it is possible to calculate traction and normal forces due to each existing wave. So, it is shown that each of the traction and normal forces consists of five components. Then, the effect of some important design parameters on the calculated components of forces is analyzed. Results by the proposed model have been compared with those evaluated by finite-element method and with experimental measurements. [ABSTRACT FROM PUBLISHER]

This study is devoted to analyzing the thermal buckling behavior and natural vibration characteristics of a uniformly heated rectangular thin plate with two adjacent in-plane frictional sliding edges. These sliding edges are initially at a stick status under the friction forces, and may slightly slip due to the thermal expansion of the plate until the sliding edges contact the stops, i.e. the bounds of the clearances. In the study, both temperature dependencies of material properties and friction coefficients are taken into consideration. For each case, the explicit equations for the buckling temperature rise and the natural frequencies of the plate are derived. Then, some parametric studies are made to reveal the influences of both normal forces and clearances on the critical buckling temperature rise and the natural vibration characteristics of the plate. The results show that both normal forces and clearances have significant influences on the critical buckling temperature rise and the natural frequencies of the plate, especially for the square plate, which has repeated natural frequencies. These results enable one to adjust the normal forces and the clearances in design in order to improve the mechanical performance of a heated rectangular thin plate. [ABSTRACT FROM AUTHOR]

This paper presents the normal force phenomena for static and steady shear mode in magnetorheological (MR) fluid. The results of the study show that, in the static mode, with the magnetic flux density increasing, the normal force will increase until the maximum, and then reduce to a steady value, and during the increasing stage, it can be expressed as F N =4667* B 2.48 approximately; however, in the steady shear mode, only when the magnetic flux density achieves a certain value, the normal force phenomena will be observed clearly, and with the increasing of magnetic field, the normal force reaches the maximum, and then also decreases to a steady value. Besides, by defining the time parameters of dynamic response, the dynamic response of normal force is studied. If the shear plate is stationary, from the magnetic field on to a stable normal force produced, the response time is about 25.11 ms. [ABSTRACT FROM AUTHOR]

This paper presents a new nonlinear model of the normal force that arises during compliant contact between two spheres, or between a sphere and a flat plate. It differs from a well-known existing model by only a single term. The advantage of the new model is that it accurately predicts the measured values of the coefficient of restitution between spheres and plates of various materials, whereas other models do not. [ABSTRACT FROM PUBLISHER]

Main landing gear is important part in aircraft, its help the aircraft to takeoff ,landing, and taxing in the ground .This part subject to high stress at landing due to impact, there are two important force act on landing gear during touch, Normal force and a spin-up back force .Normal Force is a great force that act on landing gear and its generate due to Normal impact and its cause to bend landing gear to up , this force can be calculated form Newton second law, and the spin-up back force generated at touch when the tire not rotate causing the landing gear leg to bend to backward the value of this value can be assumed equals to 0.5 from the normal force. In this study this forces type are considered to make stress analysis of the landing gear for Cessna 152 during touchdown time, after that three model are considered to reduce value of stress on this landing gear by keeping the dimension and material as on original model and making positive curves on the landing gear leg, and shown that when making the positive curve this will reduce the value of the stress and deflection on the landing gear depending on the principle of bending moment in the beams. [ABSTRACT FROM AUTHOR]

This study develops a novel mutual capacitive tactile sensor for a touch panel with shifted finger-type electrodes with high sensitivity and other benefits. This tactile sensor detects normal, shear, and pulling forces with good simultaneous visible transmittance and flexibility for the next generation of 3-D flexible portable displays. The tactile sensor is composed of polyethylene terephthalate, gold, indium tin oxide, and polydimethylsiloxane. It exhibits 75% transmittance on average in the visible region, 0.04-N force resolution, and 1.5-pF/N responsiveness. The finger-type electrode design improves sensitivity by 112%–4100%, depending on the number of fingers and shifted direction. This study conducts theoretical calculations, simulations, fabrication, and measurements.\hfill[2012-0243] [ABSTRACT FROM AUTHOR]