چكيده به لاتين
This thesis is aimed to define the behavior of railway ballasted track in longitudinal direction and also determine the portions for each part of ballast geometry on track longitudinal resistance. So, according to the last investigations, two special bearing was needed to implementing the experimental tests. In this regard a loading frame with considering special test conditions has been build in the track laboratory of school of railway engineering. The bearing structure is included two steel bearing with an embedded concrete structure in soil, which can be able to stand against the load horizontally. A hydro-electric loading system including two hydraulic jack has been provided to loading the track and complete the device. The values of force and displacement has been recorded by a central data logger which connected to LVDTs and Loadcells sensors.
In the following, the comprehensive test plan is defined after the preparation of test conditions. Totally 9 cases including, test plan without crib ballast and shoulder, test plan just with crib ballast and test plan with crib ballast and shoulder. In according to increase the accuracy of the results, each test has been done 2 times and the mean value has been considered. Finally, track longitudinal resistant has been obtained 22.83 kN/mm for the case with crib ballast and shoulder. As found in results, the crib ballast significantly increase the longitudinal resistance and make it more than 4.11 times greater than case without crib ballast. The result of study indicate that the longitudinal resistance percent from the sleeper base, crib ballast and shoulder are 21%, 61% and 12%.
