คอนกรีตและวัสดุก่อสร้าง
เอกสารมาตรฐาน
สหรัฐอเมริกา
AASHTO
M 273-22
Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers with Less Than 2 ft of Cover Subjected to Highway Loadings
2022
15
HM42-2022 part 1
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.