Investigation of dynamic loads in transmissions of heavy dump trucks when working on steep slopes

Abstract

Dynamic loads in the transmissions of heavy dump trucks during operation on steep slopes are a critical factor determining the reliability and durability of power units. The conducted research is aimed at a comprehensive analysis of the nature and intensity of dynamic impacts in transmission elements when operating on slopes above $15^{\circ}$. The methodology includes experimental measurements of dynamic loads on dump trucks with a lifting capacity of 45-90 tons, mathematical modeling of transmission load, and finite element analysis of critical components. The empirical base of the study covers 847 measurements under real-world operating conditions at slopes of $12-24^{\circ}$ under various loading conditions. The results show an excess of the calculated dynamic loads by 2,3-3,7 times when overcoming steep climbs with a full load. The maximum peak torque values reach 47,2 kN m in the main gear with a nominal value of 19,8 kN m. The dynamic loading coefficient varies from 1.85 to 4.12, depending on the angle of inclination and speed of movement. Spectral analysis revealed the dominant frequencies of dynamic impacts in the ranges of 8-15 Hz and 23-31 Hz, corresponding to the resonant characteristics of the transmission elements. A correlation has been established between the slope angle and the intensity of dynamic loads with a coefficient of determination $R2=0.847$. The results obtained indicate the need to adjust the methods of design calculation of transmissions and the development of adaptive control systems to minimize dynamic impacts.