The wheeled running gear of an agricultural tractor must have sufficient traction and coupling properties to ensure that the tractor fulfills its main function. The solution to these problems depends to a large extent on the search and implementation of measures for improving and developing new tire designs, which are the main element of the wheel drive that meets modern requirements. The developing of new pneumatic tires requires creating a new formulation of rubber and materials, the use of rubber-oligomeric compositions that allow implementing new, advanced technologies in the manufacture of tires. Currently, tires based on rubber-oligomeric compositions are being created. In particular, the Austrian company Lim developed a range of wide-section tires based on oligomers. As a result of tests of tires for class 3 tractors, it was determined that the oligomer tire 66×43.00-25 has the best traction and energy performance on all supporting foundations, compared to the serial tire 21.3R24.

The objective of flood frequency analysis (FFA) is to associate flood intensity with a probability of exceedance and for making probabilistic estimates of a future flood event in Allala basin based on the historical discharge record at Sidi Akkacha gauging station, the peak floods discharge of Allala river for 5, 10, 50, 100 years return period are estimated using exponential distribution and the stage at different position of river are calculated using HEC RAS model . Based on the modeling study carried out considering 62 cross sections for 8 km length of river, The Output HEC-RAS model show that the existing embankments system on the banks of Allala River is not sufficient to resist the peak flood discharge of 100 years return period, water level profile shows that a maximum of 1.25m in left bank((at 1.2 km downstream) is needed to protect the inundation of the low laying areas of Old tenes.

Experimental studies of the impact of agricultural mobile machinery movers on the soil are seasonal in nature and require complex experimental equipment. The complexity of the physical processes occurring in the elastic wheel-ground system requires the introduction of many assumptions and limitations that reduce the accuracy of the results, according to the design of simulation models performed in the software environment. The aim of the research was to study the influence of the design parameters of the tire on the efficiency of the normal deflection along the contact spot zone X. Studies have shown that 65% to 77% of the normal deflection of the tire is used when passing the contact spot. The reinforcement parameters of the tire frame have the greatest impact on the efficiency of the normal deflection along the contact spot zone. With an increase in the number of layers of the frame cord from 2 to 8, the coefficient of usability of the normal deviation for the stroke of the contact spot decreases from 0.761 to 0.689, with an increase in the angle of inclination of the frame cords - decreases from 0.755 to 0.693.

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In order to ensure safe working conditions for drivers, strict requirements are imposed on the smooth running of agricultural vehicles. The purpose of this research was to study the vibration load on the driver’s seat when driving vehicle under agricultural conditions. Studies have revealed that the standard KamAZ-43255 car seat string system effectively damps vibrations with the frequency of more than 16 Hz, and practically does not damp vibrations below 4 Hz. It was determined that: at all speeds, the maximum values of vibration acceleration in the vertical plane are located in the second octave at the frequency of 2.0 Hz; peak values of vibration acceleration of the driver’s seat in the horizontal plane are located in the third octave at frequencies of 3.15 4.1 Hz; maximum mean square accelerations in the vertical plane are 3.76 times higher than the maximum permissible standards; at vehicle speed of V = 20 km/h, the acceleration of the driver’s seat in the vertical plane exceeds the permissible values in 3.9 times, in the horizontal plane it exceeds the permissible values in 2.75 ... 2.79 times. Therefore, on agricultural vehicles, it is necessary to install spring systems that are adaptive to operating conditions.