Quick Facts Flashcards
Handicap Stalls Maximum Distance From Building
Maximum 100 FT from building entries
Drop Off Zone Locations
Should be located as close as possible to primary entryways
No grade changes should exist between road surfaces and adjacent walkways
Vehicular connections to drop-offs, site entrance and parking areas should be direct
Site Entrances
Should be well identified with obvious relationship to the buildings and sites they serve
Waiting Area Locations
Should be located within 300 ft of building entry
Avoid traffic congestion
Overhead shelter should be provided for protection from weather
Adequate seating and lighting should also be provided
Walkways
Should provide clear and direct routes throughout sites
surfaces should be firm and level
curb cuts and ramps should be provided where necessary
accessible walkways should consist of closed loops rather than dead ends
Site Entrances
Should be well identified with obvious relationships to the buildings and sites they serve
Signage
Clear and legible signage should be provided to direct pedestrians to various destinations
Building Entries
Should be clearly identified
Combined means of entry should be provided for handicapped individuals (i.e. both ramps and stairs)
Public facilities should be located near accessible entryways (lavatories, phones, drinking fountains, etc.)
No grade changes should exist between entryways and these facilities
Objects should not protrude into pedestrian pathways above a …
27 in. height
Crown of Improved Streets
Streets, Driveways, and Parking Areas
Gradients
Maximum 3%
Minimum 1%
Preferred 2%
Crown of Unimproved Streets
Streets, Driveways, and Parking Areas
Gradients
Maximum 3%
Minimum 2%
Preferred 2.5%
Slope of Shoulders
Streets, Driveways, and Parking Areas
Gradients
Maximum 15%
Minimum 1%
Preferred 2-3%
Longitudinal Slope of Streets
Streets, Driveways, and Parking Areas
Gradients
Maximum 20%
Minimum 0.5%
Preferred 1-10%
Longitudinal Slope of Driveways
Streets, Driveways, and Parking Areas
Gradients
Maximum 20%
Minimum 0.25%
Preferred 1-10%
Longitudinal Slope of Parking Areas
Streets, Driveways, and Parking Areas
Gradients
Maximum 5%
Minimum 0.25%
Preferred 2-3%
Cross Slope of Parking Area
Streets, Driveways, and Parking Areas
Gradients
Maximum 10%
Minimum 0.5%
Preferred 1-3%
Longitudinal Slope of Sidewalks
Concrete Walks
Gradient
Maximum 10%
Minimum 0.5%
Preferred 1-5%
Cross Slope of Sidewalks
Concrete Walks
Gradient
Maximum 4%
Minimum 1%
Preferred 2%
Approaches, Platforms, Etc.
Concrete Walks
Gradient
Maximum 8%
Minimum 0.5%
Preferred 2%
Service Areas
Concrete Walks
Gradient
Maximum 10%
Minimum 0.5%
Preferred 2-3%
Concrete
Concrete Terrace and Sitting Areas
Gradient
Maximum 2%
Minimum 0.5%
Preferred 1%
Flagstone, Slate, Brick
Terrace and Sitting Areas
Gradient
Maximum 2%
Minimum 0.75%
Preferred 1%
Recreation, Games, Etc.
(Noncompetitive)
Lawn Areas
Gradient
Maximum% 5 1 ???
Minimum% 2-3
Grassed Athletic Fields
Lawn Areas
Gradients
Maximum 2%
Minimum 0.5%
Preferred 1%
Lawns and Grass Areas
Lawn Areas
Gradient
Maximum 25%
Minimum 1%
Preferred 5-10%
Berms and Mounds
Lawn Areas
Gradient
Maximum 20%
Minimum 5%
Preferred 10%
Mowed Slopes
Lawn Areas
Gradient
Maximum 25 (3:1) Preferred 20%
Unmowed Grass Banks
Lawn Areas
Gradient
Maximum: Angle of Repose
Preferred: 25%
Planted Slopes and Beds
Lawn Areas
Gradient
Maximum 10%
Minimum 0.5%
Preferred 3-5%
Spatial Standards for Roads
Pavement Widths
Single Lane Road
10-14 ft
Spatial Standards for Roads
Pavement Widths
Two-Lane Road
20-24 ft
Spatial Standards for Roads
Pavement Widths
Four-Lane Road
20-24 ft either direction
Spatial Standards for Roads
Pavement Crown
Natural Soil
1/2 in : 1 ft
Spatial Standards for Roads
Pavement Crown
Gravel, Crushed Stone
3/8-1/2 in : 1 ft
Spatial Standards for Roads
Pavement Crown
Intermediate-Type Bituminous
1/4-3/8 in : 1 ft
Spatial Standards for Roads
Pavement Crown
High-Type Bituminous
1/8-1/4 in : 1 ft
Spatial Standards for Roads
Pavement Crown
Concrete
1/10 - 3/16in : 1 ft
Spatial Standards for Roads
Pavement Crowns
Brick or Stone
1/4 in : 1 ft
Spatial Standards for Roads
Shoulders
Minimum Width
1 ft
Spatial Standards for Roads
Shoulders
Minimum Desirable Width
2 ft
Spatial Standards for Roads
Shoulders
Preferred Width
8-10 ft
Spatial Standards for Roads
Shoulders
Slope
1/2 in : 1 ft approx 4%
Spatial Standards for Roads
Side Slopes
Slope
4:1
Spatial Standards for Roads
Back Slopes
Earth, minimum
1 1/2 : 1
Spatial Standards for Roads
Back Slopes
Earth, preferred
2:1 or 3:1
Spatial Standards for Roads
Back Slopes
Ledge rock, minimum
1/4 : 1
Spatial Standards for Roads
Back Slopes
Shale
1/2 : 1
Spatial Standards for Roads
Fill Slopes
Earth, minimum
2:1
Spatial Standards for Roads
Fill Slopes
Earth, preferred
4:1
Spatial Standards for Roads
Ditches
Minimum depth
1-2 ft. below shoulder elevation
Spatial Standards for Roads
Ditches
Maximum inslope
3:1
Surface Soil
A horizon
6-24”
Dark gray colored - high organic matter, high biotic activity, abundant roots, commonly leached
Should be stripped from construction site, stockpiled for backfill in planting areas
Not suitable for fill under construction
Subsurface
A Horizon
6-24”
Moderately dark - many roots, moderate organic matter, commonly leached
May be used as fill under topsoil and may respond to compaction under some construction
Subsoil
B Horizon
6”-8’
Below plow depth - brown or reddish colored - more clay than surface, fewer roots
Not desirable for plant growth but may make good compacted subsurface for construction*
*Depends upon soil quality and type of construction anticipated
Lower Subsoil
B Horizon
6”-8’
More yellowish and less clay - fewer roots than subsoil, less aeration than above
Not desirable for plant growth but may make good compacted subsurface for construction
*Depends upon soil quality and type of construction anticipated
Parent Material
C Horizon
Unconsolidated - slightly weathered rocky mass from which soil develops. No biotic activity, few roots
Good base course material when properly placed and compacted for construction.
Bedrock
C Horizon
Consolidated rock.
Three Major Groups of Rock
Igneous
Sedimentary
Metamorphic
Igneous Rock
Solidified from a molten state, either at or beneath the surface of the earth.
Crystalline, typically not exhibiting a grain
Breaks irregularly depending on its composition
Sedimentary Rock
Made from the sedimentation of soil, plant, and animal remains that have hardened as a result of pressure, time, and the deposition of natural cements, typically at ocean depths
Will fracture along the planes of sedimentation
Metamorphic Rock
Consists of previously igneous or sedimentary rock that has been altered by extreme heat and pressure, either at great depths of along tectonic fault lines, etc. It often exhibits some veining or foliation, which may fracture naturally as well as during blasting and excavation
In preparing a grading plan that involves rock, the most useful data includes:
(1) the amount of soil cover, or depth of earth to rock
(2) how much of the top layer rock is loose and can be easily broken
(3) how much of the rock will have to be blasted
(4) the basic type of rock
Cost of blasting and moving rock
Typically 7 to 10 times higher than moving dry, deep, moderately cohesive soil
Swell
increase of volume of soil when dug
when soil or rock is dug or blasted out of its origin position breaking into particles or chunks creating more spaces and adding to its bulk
Rational Method
Q = KCIA
Q=Peak Discharge of runoff in ft3/sec
K=Constant 1.0 for US
C=Runoff coefficient (ratio of runoff to rainfall)
I=Rainfall intensity at time of concentration in in/hr
A=Watershed area in acres
Human Cone of Vision (the fixed eye)
Approximately 30 degrees vertically
and 60 degrees horizontally
with angles of acute vision somewhat less than this
Surfacing and Paving
Climate
Hot Arid
A wide variety of materials are available in this climate zone.
Materials are typically light in color to avoid heat absorption, and may include glazed tiles and porous finishes due to low humidity and relatively stable temperature ranges.
Surfacing and Paving
Climate
Hot Humid
Drainage is critical to prevent build-up of mosses and algae, and to account for intense periods or precipitation. Light colors are often used to avoid heat absorbtion. Stable temperatures provide for a wide variety of materials.
Surfacing and Paving
Climate
Temperate
Darker colors are typical to absorb radiant solar energy. Frost/thaw cycles require care in aggregate base preparation and subdrainage. Heavy snow regions must account for abrasive cleaning practices. Mortared unit pavers required heavy maintenance in extensive applications.
Surfacing and Paving
Climate
Cold
Cold climate areas require similar treatments as the temperate zone, but with more restrictions. Flexible pavements are preferred over rigid and mortared unit pavers. Reinforcing steel must be placed carefully to avoid damage through chemical assault, or extreme expansion coefficient differentials within concrete slabs and curbs.
Surfacing and Paving
Subgrade
Well drained soils
These soils are ideal for construction with regard to permeability and bearing capacity and typically require only normal site preparation to serve as pavement subgrades
Surfacing and Paving
Subgrade
Clay Soils
These colloidal soils are subject to swelling due to moisture infiltration and have a high potential for lateral shearing. Vibration from vehicular loading may produce a pumping action resulting in upward migration of fines into aggregate bases. Freeze/thaw actions create severe construction problems requiring dewatering, extra aggregate and fabric filtration and reinforcement.
Surfacing and Paving
Subgrade
Roof Structures
Pavement design is highly restricted due to loading and drainage requirements. Special drain mats and insulation are typically required under finish pavement surfaces
Mitigation options
Practicable actions that rectify, reduce over time, and compensate for impacts.
Involve the purchase and protection of existing wetland through conservation easements and deed restrictions. - “Preservation”
Mitigation can also involve improving the function and value of an existing degraded wetland and is referred to as “enhancement”
“Restoration” is putting back a wetland that once existed
“Creation” converting an upland or non wetland area to a wetland
Another option includes the purchase of “credit” is an approved mitigation bank, where wetlands have already been preserved or created ahead of project impacts, and sometimes by a third party
Mitigation
Undertaken either on a project site or off-site, in close proximity and in the same watershed to where an impact occurred.
Requirement to have buffers.
(Buffer is area adjacent to wetland that functions to protect the wetland from adjacent land use disturbances)
Recommended buffer ranges in width depending upon buffer goal and level of wetland protection being achieved. Some literature specifies a minimum 1,000 feet for maintenance of high-quality wetlands. Within this dimension, buffers that are 50 to 100 feet wide can support some water quality improvements, while buffers of 100 to 350 feet or more can provide some wildlife habitat functions.
