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Heavy vehicles commonly use dual tires on their load and traction axles. As the only vehicle component involved in force transmission to the road, the tire is an important element in the road damage process. In this context, two factors involved are the tire's supported load and inflation pressure. Traditional practical assumptions are that each of the tires in dual arrangement supports the same load, and that the contact patch pressure is very similar to the tire's inflation pressure. To provide data about the load distribution and contact pressure in the tire's contact patch, a lab experimental study was carried out. For that, a lab device was used to determine the static load and pressure in the contact patch, using three different sets of heavy duty radial tires subjected to several combinations of supported load and inflation pressure.

Most of road accidents are caused by human factors. However, there are other factors involved in the occurrence of vehicular crashes, such as the physical condition of the road and vehicle itself. In order to increase road safety is essential to fully understand the interaction of those factors on vehicle's dynamic behavior, especially on heavy vehicles due to their greater mass, dimensions and potential damage that can provoke. This document presents information about the effect of some road surface irregularities on dynamic behavior of a three-axle heavy vehicle, based on a road with an ideally good condition (baseline). To do that, a numerical simulation model that includes both vehicle and road is used. It is able, at some degree, to simulate surface road conditions, such as potholes, friction coefficients at height levels of adjacent lanes.

The dynamic behavior of heavy vehicles moving on roads depends on load magnitude and its distribution, and a special concern may be directed to tankers. Liquid cargo at partial filled levels exhibits sloshing during vehicle longitudinal displacement, generating some forces which might alter vehicle's directional response and traction control. To attenuate the sloshing dynamic effect, transversal plates (baffles) are placed inside the container but increasing the structural container mass, arising vehicle's mass center and decreasing vehicle's useful load capacity. An experimental study on the effects of fill level and number of baffles on the sloshing attenuation is presented. For doing so, an instrumented scaled experimental tank of elliptical transversal section is used with water as liquid cargo, and longitudinal sloshing force is measured.

The sloshing behavior of a liquid cargo is an issue that needs to be taken into account when evaluating the dynamic performance of tankers. In general, hazardous liquid materials require a free volume into the tank to absorb thermal expansion changes; therefore, tank has to be filled partially. Under that condition, sloshing is produced at the liquid surface which interacts with container walls generating forces that affect the vehicle’s behavior. In this work, results obtained from experimental tests carried out in a scaled elliptical-transversal-section tank for different filling levels, baffles’ geometries, and baffles’ arrays are presented. Tank is instrumented so that longitudinal forces due to sloshing can be measured when tank is suddenly stopped. The analysis of the results allows identifying the best baffle configuration to be applied in order to attenuate the longitudinal sloshing generated when the vehicle is moving on highways.

In this paper, the importance of determining the lateral acceleration to characterize terrestrial vehicle behavior and its performance is addressed. Also, the technical difficulties to measure such acceleration and its dependency with vehicle roll angle are described. In the analysis of the motion of the vehicle's center of gravity (CG) and regarding to transversal acceleration components, the acceleration of gravity is taken into account to determine the roll angle, the lateral acceleration and the behavior of vertical acceleration component. As a result, and based upon the principles of operation of accelerometers, a scheme for a simple instrumentation to estimate the roll angle and lateral acceleration in an experimental assessment, is suggested as well.