Improvement in the design and manufacture of pre-stressed concrete railway sleepers

摘要

560,521. Railway sleepers. PRESTRESSED CONCRETE CO., Ltd., and MAUTNER, K. W. Feb. 12, 1943, No. 2326. [Class 104 (ii)] Reinforced pre-stressed concrete sleepers are of inverted trough shape either at the end portions only or at both ends and middle, and the hollow spaces at the ends are filled with ordinary concrete, wood, &c. The reinforcing wires r are arranged so that the distance e1 of their centres of gravity CS in the end portions from the centres of gravity CG of the end portions is greater than and may be of opposite sign to the corresponding distance e2 in the middle portion. The difference between the two distances may be increased by arranging supplementary stretched steel reinforcement s bonded to the concrete in the middle portion but not in the ends.