Difference between revisions of "Category:233 At - Grade Intersections"

From Engineering Policy Guide
Jump to: navigation, search
m (article construction)
m
 
(7 intermediate revisions by one other user not shown)
Line 1: Line 1:
 
[[Image:233 Photo 1.jpg|180px|right]]
 
[[Image:233 Photo 1.jpg|180px|right]]
 
An at-grade intersection is an area where two or more roadways join or cross.  It also includes the roadside facilities for traffic movement within the area.  Each intersection involves through or cross-traffic movements on one or more roadways and may involve turning movements between these roadways.  The main objective of the intersection is to facilitate the convenience, ease, and comfort of people traversing the intersection while enhancing the safe and efficient movement of motor vehicles, bicycles and pedestrians.  To accomplish this task, the intersection must have the capacity to handle all the volume of traffic flowing through it.
 
An at-grade intersection is an area where two or more roadways join or cross.  It also includes the roadside facilities for traffic movement within the area.  Each intersection involves through or cross-traffic movements on one or more roadways and may involve turning movements between these roadways.  The main objective of the intersection is to facilitate the convenience, ease, and comfort of people traversing the intersection while enhancing the safe and efficient movement of motor vehicles, bicycles and pedestrians.  To accomplish this task, the intersection must have the capacity to handle all the volume of traffic flowing through it.
{|style="padding: 0.3em; margin-left:15px; border:1px solid #a9a9a9; text-align:center; font-size: 95%; background:#ffddcc" width="210px" align="right"  
+
{| style="padding:0.3em; margin-left:15px; margin-right:10px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="270px" align="right"
 
|-
 
|-
|'''Rural Expressway, Median Crossovers'''
+
|'''CAP-X Worksheet'''
 
|-
 
|-
|[http://library.modot.mo.gov/RDT/reports/Ri98009/RDT01011.pdf Report 2001]
+
|The [http://tsi.cecs.ucf.edu/index.php/cap-x Capacity Analysis for Planning of Junctions] is a tool that districts can use to consider alternative at-grade intersection types based upon peak flow volumes.
|-
+
|[http://library.modot.mo.gov/RDT/reports/RI98009B/RDT04013.pdf Report 2004]
+
|-
+
|[http://library.modot.mo.gov/RDT/reports/RI98009b/Brf04013.pdf Summary 2004]
+
|-
+
|'''See also:''' [http://www.modot.gov/services/OR/byDate.htm Innovation Library]
+
 
|}
 
|}
There are five basic elements to be considered in the design and operation of an intersection
+
 
 +
There are five basic elements to be considered in the design and operation of an intersection:
  
 
* [[media: 233 Human Factors.doc|Human factors]]
 
* [[media: 233 Human Factors.doc|Human factors]]
Line 29: Line 24:
 
* [[233.4 At-Grade Intersections with Signal Control|Signal control]]
 
* [[233.4 At-Grade Intersections with Signal Control|Signal control]]
  
It is important to provide adequate [[230.1 Horizontal Alignment#230.1.1.6 Sight Distance|sight distance]] clear of obstructions within the functional area of the intersection to ensure a driver’s view of other vehicles is not blocked.
+
It is important to provide adequate [[230.1 Horizontal Alignment#230.1.6 Sight Distance|sight distance]] clear of obstructions within the functional area of the intersection to ensure a driver’s view of other vehicles is not blocked.
  
 
While most individuals understand intersections occur at roadway crossings, there are other types of intersections:
 
While most individuals understand intersections occur at roadway crossings, there are other types of intersections:
Line 37: Line 32:
 
* [[233.1 At-Grade Intersections - Driveways and Entrances#231.1.1.2Roadway Approaches and Driveways|Driveways]]
 
* [[233.1 At-Grade Intersections - Driveways and Entrances#231.1.1.2Roadway Approaches and Driveways|Driveways]]
 
* [[643.4 Railroads|Railroad-highway grade crossings]]
 
* [[643.4 Railroads|Railroad-highway grade crossings]]
 +
[[Image:233 Photo 3.jpg|180px|right]]
  
 
Other factors can also affect the efficient operation of an intersection.  These are:
 
Other factors can also affect the efficient operation of an intersection.  These are:
[[Image:233 Photo 3.jpg|180px|right]]
+
 
* The presence of [[641.1 Bicycle Facilities|bicyclists]]
+
* The presence of [[:category:641 Bicycle Facilities|bicyclists]]
* The presence of [[642.1 Pedestrian Facilities|pedestrians]]
+
* The presence of [[:Category:642 Pedestrian Facilities|pedestrians]]
 
* The presence of [[:category:901 Lighting|lighting]]
 
* The presence of [[:category:901 Lighting|lighting]]
  
Signalized intersections can be considered for expressways that pass through communities.  In a rural area, a designer is not to consider including a signalized intersection for a new expressway, although one may be installed at an existing expressway intersection with the recommendation of the Traffic Division.  The distance between intersections along MoDOT roadways is dependent on whether the road is major or minor, rural or urban.  The [[:category:940 Access Management|Access Management Guidelines]] is to be used to determine desirable spacing of at-grade intersections.  The NCHRP 500 series is a good source of information when considering improvements at an at-grade intersection.
+
 
 +
{|style="padding: 0.3em; margin-left:15px; margin-right:10px; border:1px solid #a9a9a9; text-align:center; font-size: 95%; background:#ffddcc" width="210px" align="right"
 +
|-
 +
|'''Rural Expressway, Median Crossovers'''
 +
|-
 +
|[http://library.modot.mo.gov/RDT/reports/Ri98009/RDT01011.pdf Report 2001]
 +
|-
 +
|[http://library.modot.mo.gov/RDT/reports/RI98009B/RDT04013.pdf Report 2004]
 +
|-
 +
|[http://library.modot.mo.gov/RDT/reports/RI98009b/Brf04013.pdf Summary 2004]
 +
|-
 +
|'''See also:''' [http://www.modot.gov/services/OR/byDate.htm Innovation Library]
 +
|}
 +
{|style="padding: 0.3em; margin-right:9px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="160px" align="left"
 +
|-
 +
|'''Additional Information'''
 +
|-
 +
|[http://www.fhwa.dot.gov/publications/research/safety/09060/ FHWA's Alternative Intersections/Interchanges Report]
 +
|}
 +
 
 +
Signalized intersections can be considered for expressways that pass through communities.  In a rural area, a designer is not to consider including a signalized intersection for a new expressway, although one may be installed at an existing expressway intersection with the recommendation of the Highway Safety and Traffic Division.  The distance between intersections along MoDOT roadways is dependent on whether the road is major or minor, rural or urban.  The [[:category:940 Access Management|Access Management Guidelines]] is to be used to determine desirable spacing of at-grade intersections.  The NCHRP 500 series is a good source of information when considering improvements at an at-grade intersection.

Latest revision as of 12:21, 29 June 2017

233 Photo 1.jpg

An at-grade intersection is an area where two or more roadways join or cross. It also includes the roadside facilities for traffic movement within the area. Each intersection involves through or cross-traffic movements on one or more roadways and may involve turning movements between these roadways. The main objective of the intersection is to facilitate the convenience, ease, and comfort of people traversing the intersection while enhancing the safe and efficient movement of motor vehicles, bicycles and pedestrians. To accomplish this task, the intersection must have the capacity to handle all the volume of traffic flowing through it.

CAP-X Worksheet
The Capacity Analysis for Planning of Junctions is a tool that districts can use to consider alternative at-grade intersection types based upon peak flow volumes.

There are five basic elements to be considered in the design and operation of an intersection:

Intersections having three or four legs are the most common and efficient in their operation. Intersections with more than five legs are to be avoided. Basic traffic management at an intersection can be placed in one of the following categories:

233 Photo 2.jpg

It is important to provide adequate sight distance clear of obstructions within the functional area of the intersection to ensure a driver’s view of other vehicles is not blocked.

While most individuals understand intersections occur at roadway crossings, there are other types of intersections:

233 Photo 3.jpg

Other factors can also affect the efficient operation of an intersection. These are:


Rural Expressway, Median Crossovers
Report 2001
Report 2004
Summary 2004
See also: Innovation Library
Additional Information
FHWA's Alternative Intersections/Interchanges Report

Signalized intersections can be considered for expressways that pass through communities. In a rural area, a designer is not to consider including a signalized intersection for a new expressway, although one may be installed at an existing expressway intersection with the recommendation of the Highway Safety and Traffic Division. The distance between intersections along MoDOT roadways is dependent on whether the road is major or minor, rural or urban. The Access Management Guidelines is to be used to determine desirable spacing of at-grade intersections. The NCHRP 500 series is a good source of information when considering improvements at an at-grade intersection.