MSTE PRO MAX Flashcards
(170 cards)
It include cost estimates for various parts of the project and are used to evaluate the acceptability of bids and the financial feasibility of the project.
Estimates
This refers to drawing, usually
accompanied by notes, of various aspects or
components of the design.
Plans
It provides the detailed requirements for the materials, equipment and workmanship
to be incorporated into the project.
Specifications
Reaction times vary widely. As a result, the usual practice is to use a single, rather conservative value. AASHTO suggests a value of ____ in its Policy on Geometric Design of
Highways and Streets.
2.5 sec
It refers to establishment of horizontal and vertical alignments and cross section, based on considerations such as operating characteristics of vehicles, design standards, and drainage.
Geometric Design
It is the distance required to see an object 0.15 m high on the roadway.
Stopping sight distance
It is the distance required to see an oncoming vehicle of a certain minimum size.
Passing sight distance
It is defined as the maximum safe speed that can be maintained over a specified section of highway when conditions are so favorable that the design features of the highway govern.
Design Speed
This is a drawing of the facility as it would look to an observer directly above it.
Plan View
This drawing has elevation as its vertical axis, and horizontal distance, as measured along the centerline of the facility, as its horizontal axis.
Profile
This view has elevation as its vertical axis and horizontal distance, measured perpendicular to the centerline, as its horizontal axis.
Geometric Cross Section
This applies to curved facilities, such as highways or railways, only. It consists of a graph with roadway or railway cross- slope versus horizontal distance.
Superelevation diagram
The primary consideration in the design of geometric cross sections for highways, runways, and taxiways is
drainage
The distance between the rails is what known as
standard gage
The calculation of the distance the line needs to traverse in order to gain a certain amount of
development
given a maximum grade, is known in railway practice as
elevation
Geometric design of transportation facilities must provide for the resolution of traffic conflicts. In general, these may be classified as
Merging conflicts - Conflicts occur when vehicles enter a traffic stream
Diverging conflicts - Conflicts occur when vehicles leave the traffic stream
Weaving conflicts - Conflicts occur when vehicles cross paths by first merging and then diverging
Crossing conflicts Conflicts occur when they cross paths directly
There are three basic ways of resolving crossing conflicts.
Time sharing solutions - involve assignment of the right-of-way to particular movements for particular times
Space-sharing solutions - convert crossing conflicts into weaving conflicts
Grade-separation solutions - eliminate the crossing conflict by placing the conflicting traffic at different elevations at their point of intersection
Freeway interchanges are classified primarily according to the way in which they handle left- turning traffic.
Diamond interchanges - employ diamond ramps, which connect to the cross road by means of an at- grade intersection.
Cloverleaf intersections - employ loop ramps, in which vehicles turn left by turning 270° to the right.
Direct interchanges - employ direct ramps, in which vehicles turn left by means of a left-turning ramp that is grade-separated as it crosses both traffic streams.
It is used to provide access to adjacent property.
Frontage roads
It is used to intercept traffic from local streets that do not cross the freeway.
Collector-distributor roads
Wherever the existing ground is above the constructed section, the construction is said to involve
cut or excavation
Wherever the existing ground is below the constructed section, the construction is said to involve
fill or embankment
The points at which the cut or fill slopes intersect the existing ground are referred to as
catch points