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APPENDIX E

INCREASED RAIL TRANSIT VEHICLE CRASHWORTHINESS IN HEAD-0N COLLISIONS

Closing Velocity Analysis of 6 February 1977 CTA Accident

The objective of this analysis is to calculate the speed of the Lake Dan Ryan Transit Car Train when it impacted a Revenswood Train which was stopped at the end of a curve in Chicago‘s Loop. Data for the analysis was obtained from the Chicago Transit Authority in response to IIT Research Institute letter of February 15. 1977 and other private conversations. Table 1 lists data used in the analysis

The total energy in the two consists just prior to the colli-

sion is 8 u: 2 E ‘ E1 (“0 ’25) i=1 Ii“i where V0 is the closing velocity of the impacting consist. If the data from Table 1 is substituted into this formula

‘ 2 £1 5&9 V0

Here £1 will be in in.-1b if V0 is in in.lset.

The energy reQUired to overturn the leading car of the impact-

ing consist is E0 - W1 {(JGZI&+?CZ - Ye) + 2/2]

Again substituting data from Table 1

E0 - 599,000 in.-lb The energy stored in the draft gear and drawbars due to their

stroke is given by ED - (u+s')(K-52/2 + P-S) Taking data from Table 1 this becomes

ED - 600,000 in.-1b.