Specifications for design of foundation of highway bridges and culverts General specifications for design of highway bridges and culverts Technical specifications for construction of highway bridges and culverts Code for design of ground base and foundation of highway bridges and culverts Technical specifications for application of pebble concrete to highway bridges and culverts Specifications for design and construction of highway tunnels with gas Specifications for collision design of highway bridges Specifications for design of highway immersed tunnel Specifications for landscape design of highway bridges Specification for design documents of highway maintenance engineering