3B. Barrier design

Question 1

Where can different types of barriers be found

Answer 1

AASHTO Roadside Design Guide Chapter 5

Question 2

What are the 3 types of barrier systems

Answer 2

Flexible
Semi-rigid
Rigid

Question 3

What must an end barrier not do, to be considered “crashworthy”

Answer 3

They must not, spear, vault, or roll a vehicle.

Question 4

What formula is used to determine the speed after crashing into the first barrier?

Answer 4

V1 = [Mv*Vo] / [Mv+M1]
V1 = velocity in f/s or mph
Mv= mass of vehicle (lbs)
Vo = original impact velocity (f/s or mph)
M1= Mass of sand in first barrel (lbs)

Question 5

What formula is used to determine the speed after crashing into the second barrier?

Answer 5

Vn = [Mv*V(n-1)] / [Mv+Mn]
Vn = velocity in f/s or mph
Mv= mass of vehicle (lbs)
V(n-1) = previous impact velocity (f/s or mph)
Mn= Mass of sand in nth barrel (lbs)

Question 6

What speed can we assume a vehicle will come to rest after hitting a barrier / sand barrel?

Answer 6

10 mph