AASHTO M 273-20

This specification covers single-cell, precast reinforced concrete box sections with less than 2 ft of cover subjected to highway loadings and intended to be used for the construction of culverts and for the conveyance of storm water, industrial wastes, and sewage.

A complete metric companion to M 273 has been developed—M 273M; therefore, no metric equivalents are presented in this specification.

This specification is primarily a manufacturing and purchasing specification. However, standard designs are included and the criteria used to develop these designs are given in Appendix X1. The successful performance of this product depends on the proper selection of the box section, bedding, backfill, controlled manufacture in the plant, and care that the installation conforms to the construction specifications. The owner of the precast reinforced concrete box sections specified herein is cautioned that the loading conditions and the field requirements must be correlated with the box sections specified and that inspection at the construction site must be provided.

AASHTO M 259 is to be used for box sections subjected to highway loading with 2 ft or more earth cover, or subjected to dead load only.

If load-and-resistance factor design (LRFD) is required, then use ASTM C1577.