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Here is a PDF with some question about the type 2 end treatment.

I have answers for your questions regarding the end anchorages for the MGS.

1. The post bolt, nut, and washer hardware specification is according to the Hardware Guide. Note that the specifications and the diameter are consistent for all post bolts, but the length of the bolt varies depending on the blockout and type of post used. For the BCT posts in the end anchorage, the specs should be:

a. 5/8" diameter x 10" long ASTM A307 guardrail bolt galvanized according to ASTM 153 (AASHTO M232 Class C) or ASTM B695 (AASHTO M298 Class 50)

b. 5/8" diameter A563 DH heavy hex nut galvanized according to ASTM 153 (AASHTO M232 Class C) or ASTM B695 (AASHTO M298 Class 50)

c. 5/8" diameter F436 flat washer galvanized according to ASTM 153 (AASHTO M232 Class C) or ASTM B695 (AASHTO M298 Class 50)

2. As a side comment, your details should show a 6" long, 2" Schedule 40 pipe sleeve in the BCT hole.

3. The post bolt hole in the BCT post should be 7 1/8" down from the top of the post. The detail you have shows a second hole at 10 3/8". This hole is for use with standard W-beam mounted at 27 ¾".

4. Another side comment, page 2 of your detail shows two different cable end fittings. We would prefer that you use the one shown on the bottom as it is what we test with. The end fitting should also be Grade 5 material in order to have sufficient ductility. Some people have ordered Grade 8 cable end fittings, but these are too brittle and can fracture under loading.

5. The cable anchor bracket is a standard part from the Hardware Guide (FPA01). I have attached the details from the hardware guide with the remaining dimensions.

6.


One last item to discuss was your desire to adapt the end anchorage to use white pine posts. Ron and I discussed this and we believe that it is possible, but it will require some further investigation. From the CRT work that Scott did in the white pine report, we could expect that the white pine BCT post would increase in size by around 2". This in turn would increase the size of the foundation tube and the angle of the cable to the guardrail. The larger foundation tube would increase the soil resistance of the tube, and it might need to be made shorter in order to prevent excessive loading of the anchorage. We think that this kind of change can be accomplished, but we would recommend component testing of the anchorage prior to recommending its use. The component test required would be a simple jerk test on the redesigned anchorage to verify its force vs. deflection properties.