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Path: utzoo!linus!philabs!cmcl2!seismo!brl-tgr!tgr!Nicholas.Spies@H.CS.CMU.EDU
From: Nicholas.Spies@H.CS.CMU.EDU
Newsgroups: net.railroad
Subject: Ties
Message-ID: <1591@brl-tgr.ARPA>
Date: Wed, 18-Sep-85 20:01:20 EDT
Article-I.D.: brl-tgr.1591
Posted: Wed Sep 18 20:01:20 1985
Date-Received: Sat, 21-Sep-85 10:28:28 EDT
Sender: news@brl-tgr.ARPA
Lines: 17


	 The interesting messages about rail technology prompts me to
	 ask whether any of you know what has happened to the idea of
	 using pre-stressed concrete for RR ties. Also, what is the
	 service life of rails, ties, and the track bed? As the three
	 are a integral unit it would be interesting to know what the
	 ideal qualities of each would be, which may suggest new ways
	 to build tracks requiring less maintenance, give longer
	 service life, etc. 

	 For instance, would simple heat pipes driven into the ground
	 dissipate heat and relieve thermal stress on rails or is it
	 not important enough to justify the expense? Would rails (and
	 wheels) benefit from laser annealing to reduce deformation? Or
	 is this not cost-effective? Would magnetized "sleds" using a
	 generator driven by wheels during breaking be more effective
	 than breaking only with wheels?