Glossary

ADT (Average Daily Traffic) – the count of typical traffic volumes on a given roadway in a 24-hour period.

AREMA (American Railway Engineering and Maintenance-of-way Association) – governing body/code for railway engineering in the United States of America.

abutment – a substructure element at the ends of a bridge that support the main load carrying members.

Alternatives Analysis – a document produced during the scoping phase of a federally funded project which examines the various alternatives for a project and evaluates the pros and cons of each, ultimately recommending the most appropriate preferred alternative to be carried forward to final design.

arch – is a structural form consisting of heavy, sturdy abutments or buttresses and primary supporting elements having a circular, elliptical, parabolic, or other curved shape that results in the vertical loads on the structure being converted, via compressive action within the arch, into thrust forces at the abutments or adjacent arches.

Bidding Phase – The phase of a project when it is advertised for construction and contactors bid on the job.  The job is then awarded to the low bid contractor for construction.

bituminous concrete pavement (asphalt) – roadway surface constructed of a hot mixture of coarse aggregate, fine aggregate and asphaltic tar binders in place of the cementitious material which is placed and compacted to form the roadway surface.

CIP (cast-in-place) concrete – Portland cement concrete that is mixed at a ready mix plant, trucked via cement mixer to a construction site and placed in its final position in flowable form into formwork constructed on site and allowed to harden in place.

clear span – the unobstructed clear distance between the faces of the supporting elements of a structure.

closed spandrel arch – an arch structure with solid spandrel walls that contain a fill material between the arch and the roadway above.

compression – a pushing force

concrete – a flowable and formable building material that consists of aggregate (rocks), fine aggregate (sand), binder (typically Portland Cement), admixtures and water which harden to a solid stone like material which has high compressive strength.  It may be reinforced with metal bars to give it additional tensile strength.

concrete arch – is an arch structure in which the primary supporting arch elements of the structure are comprised of precast or cast-in-place Portland cement concrete.

concrete pavement – roadway surface constructed of Portland cement concrete.

contributing resource – any building, object, or structure which adds to the historical integrity or architectural qualities that make a local or federally listed historic district significant.

Construction Phase – The phase of a project after the bid phase and award of the construction contract in which the project is physically built.

crest – a vertical curve at a hill top or where the grade is becoming less steep.

design speed – the travel speed used as a design parameter for various engineering calculations for a given roadway.  The design speed is usually 5 to 10 mph higher than the intended posted speed limit of the road.

fascia – of or pertaining to the exterior faces of the bridge or the outermost girders

faux arch – having the appearance of or evoking the character of an arch shape

filled arch bridge – a concrete or stone arch bridge with earthen or aggregate fill in-between the spandrel walls.  (Walls located at each fascia of the bridge.)

filled arch – an arch bridge consisting of abutments and possibly piers and an arch or arches with closed spandrel walls containing soil or aggregate fill and capped with a pavement box and or sidewalks and parapets or railings. Frequently utilities may also be buried with the fill.

Final Design Phase – The phase of a project in which the conceptual plans from scoping and/or the preliminary plans from a preliminary engineering phase are taken to final design completion.  Permits are obtained and contact documents (bid plans, specifications and engineers estimate) are developed for use in biding and ultimately building the project.

functionally obsolete – a classification within the Nation Bridge Inspection Standards of the National Bridge Inventory and the Nation Bridge Inspection Programs of the Federal Highway Administration that mandated all bridges be inspected every two years. A bridge receives this classification when it no longer meets the current geometrical and design standards that are presently in use in designing bridges at the time of the inspection.

GP&E – General Plan and Elevation – a drawing the shows the plan view and the elevation view of a structure.

grades – the slope of a road way either up hill or down hill.

HAER (Historic American Engineering Record) – a program of the National Park Service in conjunction with ASCE (American Society of Civil Engineers) and the Library of Congress which is entrusted with setting the standards for the proper documentation of historic structures.  Visit the HEAR Collection of the Library of Congress at: http://www.loc.gov/pictures/collection/hh/

historic mitigation – measures taken to reduce the impact of or compensate for a negative impact upon a historic district or a contributing resource to a historic district.

Historic Sites Council – a gubernatorially appointed 11 member advisory board that is tasked with making recommendations to the Commissioner of the NJDEP relative to the approval, disapproval, and/or mitigation requirements for project authorization applications for public projects which impact historical properties in NJ.

horizontal alignment – the horizontal path a road follows which consists of circular curves and horizontal tangents.

individual eligibility – a historic property or structure is individually eligible for listing on the national or statewide register of historic places if it meets all of the following criteria:

• Be at least 50 years old and retain enough of its original design, architectural treatment and original construction materials to continue to represent its original character and accurately represent its original period of significance.
• Must be significant for one of the following reasons:
  • Be associated with events that have made a significant contribution to the broad patterns of our history;
  • Be associated with the lives of persons significant in our past;
  • Embody the distinctive characteristics of a type, period, or method of construction, or that represent the work of a master, or that possess high artistic values, or that represent a significant and distinguishable entity whose components may lack individual distinction; or
  • Have yielded, or have a high likely-hood to yield, important archeological information about a historical or prehistorical period.
• Has not been significantly altered after its relevant period of significance.

infill – soil or aggregate fill within the spandrel walls of a filled arch structure.

MOA (Memorandum of Agreement) – the document laying out the historical mitigation requirements and commitments agreed to in order to secure the authorization of a project.

MPT (Maintenance and Protection of Traffic) – is the traffic control plan and equipment and/or detours used to allow for safe work zones for construction while maintaining ongoing mobility of the traveling public and ensuring the safety of motorists, pedestrians and construction workers and maintaining access to, through and/or around an active roadway construction work zone.

multi-span – a bridge or structure consisting of more than one span.

NJTPA (North Jersey Transportation Planning Authority) – is the federally authorized Metropolitan Planning Organization for the 13-county northern New Jersey region. It oversees federal funding for local and regional transportation improvement projects and provide a forum for interagency (FHWA, NJDOT, and Counties and Municipalities) cooperation and public input.

offline construction – construction at an offset or a skew to the existing roadway alignment.

PIC (Public Information Center) – a public meeting held to provide the community with information on a proposed project and to gather public input in response to proposed project.

PPA (Preliminary Preferred Alternative) – the recommended preliminary design outcome from the scoping phase of a project which form the basis of the final design phase.

pavement box – the layers of constructed material that constitute the roadway which include subbase, dense graded aggregate, base course and intermediate course pavement layers, or poured concrete pavement, and surface course, wearing course and/or overlays, if any.

pier – a bridge substructure element at locations other than at the ends of a bridge that supports the main load carrying members in multi-span bridges.

posted speed limit – Codified, posted, enforceable legal speed limit for a given section of roadway.

precast concrete – Portland cement concrete that is mixed at a batch plant at or near a manufacturing facility and cast into forms and cured under controlled factory conditions to produce structural, architectural, or other cast concrete components to be used in construction.

prestressed concrete – concrete members that have additional reinforcement consisting of steel strands placed under tension prior to casting the concrete to induce an internal compressive force to the member.  This force in turn increased the load carrying capacity of the concrete member.

project limits – the physical extent of the area of construction impact of a particular project, usually given by mile post or by stationing along the proposed or existing roadway alignment.

Public Officials Briefing – a meeting held with community leaders to brief them on a project impacting their community and seek input and coordination with the local municipalities and agencies.

queuing – The building up of a line of cars in an intersection.

reinforced concrete – Portland cement concrete this is strengthened with the addition of metal bars or wire mesh within the concrete matrix to provide additional tensile strength and bending and shear resistance.

SHPO or HPO (State Historic Preservation Office) – a division of the NJDEP (New Jersey Department of Environmental Protection) responsible for evaluating and mitigating impacts to historical sites in NJ.

sag– a vertical curve at a valley bottom or where the grade is becoming steeper.

Scoping Phase – the initial phase of a federally funded project which examines the warrants for and the various alternatives for a project and evaluates the pros and cons of each, ultimately recommending the most appropriate preferred alternative to be carried forward to preliminary engineering and/or final design. A scoping study or Alternatives Analysis report is produced in the Scoping Phase which contains the analysis and recommendations to be advanced.

Scoping Study – another term for the Alternatives Analysis report from the Scoping Phase of a project.

signal timing – The phases and associated durations of the various colors a traffic signal is displaying to each of the traffic movements being controlled at a given roadway intersection.  The timing can be adjusted to facilitate the most efficient flow of traffic through the intersection.

signalized intersection – an intersection of roadways in which the traffic movements are controlled by a traffic light or lights.

span – the distance between any two faces or points of support of supporting elements of a structure, as in the distance between piers, bridge abutments, beam supports or the distance between beams themselves.

spandrel – is the space between and above two arches or between an arch and a rectangular enclosure above and behind the arch. The spandrel area of an arch bridge, viaduct or building support may either be open with exposed members supporting the structure above or closed in with a spandrel wall at the face of the arch.  A closed spandrel may also support soil or aggregate fill over the arch.

staged construction – an MPT method that utilizes partial width construction and demolition of a roadway or bridge in several stages shifting traffic between the stages in order to maintain the flow of traffic through the site while construction is ongoing.

structurally deficient – a classification within the Nation Bridge Inspection Standards of the National Bridge Inventory and the Nation Bridge Inspection Programs of the Federal Highway Administration that mandated all bridges be inspected every two years. A bridge receives this classification when the deck, superstructure, or substructure, is rated in “poor” condition (0 to 4 on the NBI rating scale of 1 to 10), which usually indicates some significant structural defects which, if left unaddressed, could substantially weaken the structure.

superstructure – The upper portion of a bridge structure consisting of the deck or roadway surface sidewalks and parapets or railings of any secondary framing that supports the deck and the main load carrying member that span the bridge opening.

substructure – the elements of a bridge that support the superstructure and hold up the main spanning elements.  The substructure elements would include piers or bents, as well as abutments.

tension – a pulling force

traffic control – devices or signage designed to manage the flow of traffic either under normal roadway conditions or through a construction zone.

twin-span arch – an arch structure consisting of two abutments and pier and two identical adjacent arch spans.

typical section – a drawing that shows the cross-sectional view of the composition of a structure.

vertical under-clearance – the minimum clear distance between the bottom most members of a bridge superstructure and the road surface, railroad tracks, ground or water over which it passes.  Required to be 23 feet.

vertical alignment – the vertical path a road takes consisting of tangent grades up and down hill connected by crest or sag vertical curves which are parabolic in shape.

vertical curve – crest or sag parabolic curves connecting tangent grades that define the vertical shape of a roadway.

vertical profile – see vertical alignment.