Figure 2.4-1 is shown as a…

Figure 2.4-1 is shown as a NCHRP-350 TL-1 barrier which has been used on low-volume roads in the United States. As far as I can tell, there is no MTO standard detail for this type of barrier. The figure seems to be taken from “Design and Evaluation of Two Bridge Railings for Low-Volume Roads” (Faller et al., 1995). As there is no MTO standard drawing, a citation to the original report should be included in the Structure Manual so designers can conduct their own research. Please also note that there is critical information missing in Figure 2.4-1 which was included in the 1995 report – a sawcut in the tension face of the post is required but is not shown.

Similarly, can reference information for Figure 2.4-2 and Figure 2.4-3 be provided for informational purposes if an MTO standard detail does not exist? Also, Figure 2.4-2 appears to be a new detail added to this version of the Structure Manual – maybe it is an issue on my end only, but this image is very blurry.