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Maximum acceleration rate:

The maximum acceleration rate is defined for each vehicle class as a function of the grade of road segment and the speed of the vehicle [Pline(1992)], i.e.:

equation341

where:

G
gradient (%);
tex2html_wrap_inline2918
maximum acceleration rate at speed V on grade G;
tex2html_wrap_inline2924
maximum acceleration rate at speed V in level terrain;
g
acceleration of gravity (32.2 ft/sec tex2html_wrap_inline2930 ).

The default values of tex2html_wrap_inline2924 for five vehicle classes and five speed categories are based on [FHWA(1980)], [FHWA(1994)] and [Pline(1992)]. These are documented in Table C.2 in Appendix C.3.


Qi Yang
Wed Feb 26 19:17:06 EST 1997