Typical Sections All graphics taken from Ch 3 of HDM CTC 440

Objectives Know what a typical section is and what may be included in a typical section

Typical Sections Show the physical shape and highway elements to be used when the project is constructed Typical sections are generally included in a set of design plans Several sections may be needed to describe a project

Typical Elements Number and width of lanes/shoulders Thickness of pavement layers Item #’s Payment limits Cut/fill slopes Ditch/gutter/curb/sidewalk locations

Control Lines Show how the typical section is located w/ respect to horizontal/vertical control HCL-horizontal control line TGL-theoretical grade line POR-point of rotation

Lane Width Show typical lane widths

Cross slopes & superelevation Show typical pavt cross slope Show superelevated sections

Pavement Sections Show pavement materials Show thickness of various layers

Superpave New Superpave (from 1999) Old design was the Marshall mix Superpave more complicated (refer to HDM Ch 3 and Pavement Design Manual)

Shoulders Shoulder width/cross slope Rollover limitations Shoulder thickness/materials Conventional (being phased out) ESAL (full-depth Shoulder break (0.7 m) Guide rail placement Lateral Support to the shoulder Delineation ARD-Audible roadway delineators

Clear Zones Distance from edge of traveled way to an actual obstacle or potential hazard. If FO are to be removed typical sections should show clear zone If not practical to provide a reasonable clear zone, a barrier system should be provided

Barriers Guide Rail Box beam Corrugated Cable Concrete Barriers

Medians-width and treatment

Curbs Type Non-mountable Mountable Traversable Combination curb-gutter Asphalt Stone

Gutters Collect runoff Use flattened and widened section for drives

Sidewalks Set back as far as practicable (snow storage, pedestrian space) Thickness (100mm or drives) Materials Concrete Asphalt (short-term) Bricks or pavers (historical/aesthetic)

Embankment (fill) slopes For maintenance and safety--should be flat as possible 1:3 max w/o guide rail 1:2 w/ guide rail

Ditches Show ditch dimensions/slopes Should provide traversable ditches (1:6 down; 1.2m-width; 1:4 out) w/in clear zone If can’t provide traversable ditches consider guide rail (or use professional judgement—guide rails in themselves can potentially be hazardous)

ROW Width Sometimes shown on typical sections

Modifications needing Typical Sections Overlays Cracking & Seating Rubblizing Lane Additions and Widening Miscellaneous Edge drains Adding curbs to existing pavts.