Midwest Guardrail System Without Blockouts J.D. Reid, R.K. Faller, R.W. Bielenberg, and K.A. Lechtenberg Midwest Roadside Safety Facility University of Nebraska-Lincoln TRB 2013 January 14, 2013

Midwest Roadside Safety Facility Acknowledgments Midwest States Pooled Fund Roadside Safety Program MwRSF Staff 2

Midwest Roadside Safety Facility Introduction Full-scale Crash Testing Comparison: blocked vs non-blocked Rail-Post Attachment Blockout Importance Conclusions 3

Midwest Roadside Safety Facility Proprietary Non-Blocked Systems T-31 Guardrail (Trinity Highway Products) Gregory Mini Spacer Guardrail (Gregory Industries) NU-GUARD-31 (Nucor Steel Marion, Inc.) 4

Midwest Roadside Safety Facility Non-Proprietary Non-Blocked Systems 5 Non-Blocked MGS for Wire-Faced Walls of Mechanically Stabilized Earth (TRB 2011)

Midwest Roadside Safety Facility Design Details 6

Midwest Roadside Safety Facility MGSNB-1: deg OIV 17.1 ft/s ORD 11.5 g 7

Midwest Roadside Safety Facility MGSNB-2: deg OIV 31.3 ft/s ORD 10.2 g 8

Midwest Roadside Safety Facility Blocked vs Non- Blocked 9

Midwest Roadside Safety Facility Pickup Truck 10

Midwest Roadside Safety Facility Pickup Truck 11

Midwest Roadside Safety Facility Pickup Truck 12 BlockedNon-Blocked

Midwest Roadside Safety Facility Pickup Truck 13

Midwest Roadside Safety Facility Small Car 14

Midwest Roadside Safety Facility Small Car 15

Midwest Roadside Safety Facility 1100c – smoother with blocks 16 BlockedNon-Blocked

Midwest Roadside Safety Facility Small Car 17 Non-Blocked Blocked

Midwest Roadside Safety Facility Advantages of the Blocked MGS Improved stability for both vehicles Reduced snag Reduced occupant risk measures 18

Midwest Roadside Safety Facility Outline Full-scale Crash Testing Comparison: blocked vs non-blocked Rail-Post Attachment Blockout Importance Conclusions 19

Midwest Roadside Safety Facility Rail-Post Attachment 20

Midwest Roadside Safety Facility Rail-Post Attachment: 2270p 21

Midwest Roadside Safety Facility Rail-Post Attachment: 1100c 22

Midwest Roadside Safety Facility Blockout Importance 23

Midwest Roadside Safety Facility Blockout Importance 24 Post 14: No Wheel Snag Major Wheel Snag BlockedNon-Blocked

Midwest Roadside Safety Facility Blockout does not eliminate wheel snag 25

Midwest Roadside Safety Facility 26

Midwest Roadside Safety Facility Conclusions and Recommendations MGS without blockouts successfully crash tested Rail effectively releases from post, even in worst case location Blocked system performs better and is recommended if space is available Special applications – see report 27