Better bridges parameters, tweaked for TTRS/ARRS:
1. first grid, suspension and cantilever bridges available in half of XIX century;
2. corrected spread and ratio of speeds and costs;
3. bridge base costs and ground levelling costs raised 8x, additionally tunnel building and water clearing costs increased 4x;
4. similar properties of suspension and cantilever bridges;
5. short bridges (concrete, grider) can be 4 tiles long (+ 2 bridge heads);
6. silicon bridge for very fast trains (vaccum tube etc).

Tracking table, sorted by year:

bridge type		year	lmin	lmax	(+2 bridge heads)		p.factor	v km/h
wood			0	0	32					4		40
grid tied		1840	1	6					10		80
suspension iron	1880	3	14					19		100
cantilever iron	1860	0	10					18		100
suspension concr.	1925	4	20					32		120
cantilever riv.	1935	2	16					52		160
concrete		1920	0	5					28		120
suspension steel	1965	5	30					70		180
grid steel		1965	0	5					90		300
cantilever welded	1990	4	26					96		300
tubular steel 1	2000	0	18					120		400
tubular steel 2	2020	2	64					180		800
tubular silicon	2040	2	32					256		4000

License:
betabridges v.0.8 for OpenTTD, created with Grfmaker, NFO adjusted manually and compiled with Grfcodec.
Copyright 2015 McZapkie

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License, version 3, as published by
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for more details.

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For betabridges NFO source code or bug tracking: mczapkie at gmail.com