NCHRP report 350
NCHRP report 350
(OP)
I am designing an extended curb that will anchor a test level 3 traffic rail per the NCHRP 350 spec and need an impact force. I know how to calculate impact forces, but the report only designates weight, initial speed, and impact angle. I need change in velocity (lateral) for the calculation. The report does give limiting occupant speed and decel (g's) and I am thiking of using those. Any thoughts or sugguestions?






RE: NCHRP report 350
RE: NCHRP report 350
AASHTO requires a design (unfactored) impact load of 400 kips for structures adjacent to a roadway that are not protected by an independent barrier.
Or you could assume a final velocity of zero and use F*deltaT = m*deltaV (impulse relation from high school physics). The smaller the deltaT, the higher the F.
Jeff
RE: NCHRP report 350
RE: NCHRP report 350
If I recall correctly, the 400 kips was for a tractor-trailer impact or a train impact.
But when the contract doesn't specify the requirements (as a recent letting project did), I bid it high to cover my butt. Didn't win the job, but I'm not eating the cost of missing it from the design-build item.
Jeff
RE: NCHRP report 350
ftp://ftp.
Thanks for your input