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One of the main concerns in road conservation and maintenance activities is the interaction between tire and road through the contact patch. The internal air pressure and the weight supported by the tire are factors that affect the force and pressure transmitted to road surface by the vehicle. An experimental study related with load distribution and pressure in the tire's contact patch is presented in this paper. For testing, a lab prototype was used to determine the static load distribution along and transversally to the tire's contact patch. Two types of tires, both for light trucks, were used: one single radial and the other bias-ply, this last type in dual configuration. Several combinations of vertically supported load and air pressure were applied to testing tires. Results showed that contact pressure is uneven in the contact patch and lower than air pressure for the radial tire, but in some cases higher for the bias-ply tires in dual configuration.

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.

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.

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.