1.1.3 Types of Construction

The RDM describes design criteria for the following categories of highway construction: resurfacing, restoration, rehabilitation, and reconstruction.

Table 1-1

gives definitions of the different highway construction categories.

**Table 1-1: Highway Construction Category Definitions**
Highway Construction Category	Definition
Resurfacing	Limited existing pavement surface repairs such as milling, spot patching, seal coat, rut repair, crack sealing, and fog sealing.
Restoration	Existing pavement structure repairs such as patching or rebuilding short sections of road, milling and hot mix overlays, shoulder edge repairs, or minor safety improvements (i.e., guardfence, pipe headwalls, etc.).
Rehabilitation	Partial or full depth pavement reconstruction on existing profile/alignment such as removal and replacement of the existing riding surface and base material, driveway improvements, ditch regrading or safety improvements (i.e., guardfence, pipe headwalls, etc.). If approved, minor lane/shoulder widening, adding medians/curbing, minor improved drainage design or intersection improvements are included.
Reconstruction	Projects that utilize an existing roadway alignment (or make only minor changes to an existing alignment) but involve a change in the basic roadway type. Changes in the basic roadway type include widening a road to provide additional through lanes or adding a raised or depressed median where none currently exists, and where these changes cannot be accomplished within the existing roadway width (including shoulders).
New Construction	Projects on a new alignment or new construction.

TxDOT designates the following as applicable design criteria in

Table 1-2

using the definitions above.

**Table 1-2: TxDOT Construction Types and Applicable Design Criteria**
Roadway Design Criteria	Highway Construction Categories	Definition
2R	Resurfacing and Restoration	Projects consist of non-freeway work on facilities not on the National Highway System (NHS) with a current ADT ≤ 2500 per lane that propose to restore the pavement to its original condition. Includes restoration of pavement structure, ride quality, or other necessary components to its existing cross section configuration. The principal purposes of these projects are surfacing and repair of the pavement structure. The addition of continuous two-way left-turn lanes (TWLTL), acceleration/deceleration lanes, turning lanes, and shoulders are acceptable as restoration work as long as the existing through lane and shoulder widths are maintained as a minimum. Work DOES NOT include the addition of through travel lanes.
3R	Resurfacing, Restoration and Rehabilitation	Projects consist of transportation projects that extend the service life and enhance the safety of a roadway including freeways and NHS roadways. In addition to the work described under resurfacing and restoration, the activities include upgrading the geometric design and safety of the facility. Work may include the upgrading of geometric features such as roadway widening, minor horizontal and vertical realignment (typically less than 10% of the project length) and improving bridges to meet current standards for structural loading and to accommodate the approach roadway width. Work DOES NOT include the addition of through travel lanes.
4R	Resurfacing, Restoration, Rehabilitation, and Reconstruction and New Construction	Projects on a new alignment or new construction. Projects that upgrade an existing roadway to meet geometric criteria for a new facility. Projects that include substantial changes in the geometric character of the highway, such as widening to provide additional through lanes, significant horizontal or vertical realignments, and major improvements to the pavement structure to improve long term service. Bridge replacement projects with ADT > 400.
5R	Mobility Corridors	Projects that are intended to regenerate, or produce new, long-term transportation opportunities including multiple modes such as rail, utilities, freight, and passenger characteristics.
Notes:
Guidance on Preventative Maintenance (PM) projects can be found in TxDOT's Maintenance Management Manual and the Maintenance Operations Manual .

1.1 Overview