Development of Emergency Track Beam Alignment for Rapid Track Beam Replacement of Straddle Monorail Transit

摘要

Prestressed concrete (PC) track beams are the important component of straddle monorail transit systems. To ensure the normal operation of straddle monorail transit, a type of prefabricated steel track beam, termed an emergency track beam (ETB), is used for rapid replacement of destroyed PC track beams. The object of this paper is to analyze the design of ETB alignment to satisfy the rapid replacement of PC track beams for all types of alignments. This paper describes the structural design and replacement principles of ETB. According to an analysis of six types of PC track beam segment alignments, two types of circular curves, R_e = oo and 180 m, are considered as the ETB plane curve, a straight line is considered as the ETB vertical curve, and superelevation can be achieved by a cast-in-place concrete layer over the running panel of the ETB. The writers quote PC track beams in Chongqing, China, for instance analysis to verify the alignment design of ETBs. The paper also presents the typical cost and construction process of ETBs in Chongqing. This paper shows that ETB structural and alignment design can fulfill the requirement of rapid replacement of PC track beams.