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Ron, attached is a PDF for the Type II Guard Fence End Terminal Standard Drawing that we use on divided roadways when the end terminal is outside the clear zone.

Will our Type II end terminal anchorage system provide the required strength to develop the capacity of the rail?  My concern is that this may be an item not studied to date based on 350 since the end terminals, temporary barrier, etc have been the main focus so far.

Bob and I briefly reviewed your detail and made a comparison to a new single, cable anchor post developed for Road Systems, Inc. and for use with the taller MGS in combination with FLEAT and SKT end treatments. In the comparison, the Ks DOT detail uses a shorter tubular post but a larger soil plate area. On the contrary, the Road Systems detail uses a longer wide flange anchor post instead of a tubular foundation member and in combination with a smaller soil plate area than currently used by Kansas.

In the absence of any testing and evaluation of your system, we may be more comfortable with Kansas increasing the length of the single anchor tube by 12 in. Please note that it may be possible that your existing system would meet the NCHRP 350 requirements for longitudinal, strong-post W-beam guardrail systems. However, we cannot make that final determination without full-scale vehicle crash testing. Therefore, in the interim and absence of testing, we recommend that you increase the tube length by 1 ft if you wish to continue the use of a single anchor tube in lieu of the two tube system adjoined with a channel strut.