Road engineering starts with the alignment and carries through to pavements and structures. Rahyaft designs road alignments and junctions, studies and designs bridges, culverts and other structures, carries out pavement studies, and prepares upgrading schemes for existing roads to improve their capacity, safety or ride quality.
The work usually runs in stages: phase 0 to choose between options, phase 1 for the preliminary design and phase 2 for construction drawings. Clients are municipalities and provincial road authorities. Examples include the road network development feasibility studies and the phase 0 and 1 studies for the streets and interchanges in Qazvin's transport master plan, both for Qazvin Municipality, and the black-spot safety plan for Isfahan province's road maintenance and transportation directorate.