Solution of the Problem of Providing Railway Track Stability in Joint Sections Between Railroad Facilities and Subgrade

The paper presents the results of design, implementation and operational observations of nonstandard track structures with variable stiffness in joint sections of bridges and tunnels with regular subgrade. Technical and economic efficiency evaluation based on long-term real data analysis was carried out.It was experimentally confirmed that the sub-rail base stiffness changes reach 5-8 times, force unevenness exists and intensive residual deformations accumulate on the approaches to bridges and tunnels under passing trains. Several designs of reinforced concrete slabs, frames and monolithic concrete were developed to smoothly change the stiffness, reduce intensive accumulations of residual deformations. Empiric relationships between the development of settlements within the structures of variable stiffness and the tonnage passed were found. Additional technical decisions were proposed to improve the performance of the structures invented. Maintenance of track approaches to bridges and tunnels cost reduction was proven.