SECTION 4
Accounting for shrinkage and compaction, what is the desired ratio of cut vs. fill?
A ratio of 1.1 to 1.2 FT3 of cut to each FT3 of fill required is often used where a balance of volumes is desired = cut/fill ratio of 1.2
Underdrainage
A specific type of subsurface drainage used to maintain proper structural conditions Ex: footing and foundation drains and lateral drains placed behind retaining walls
What street layout in relationship to contour direction will have the least impact?
Angled/diagonally across the contours. More efficient storm drainage, better relationship between structure and access, and less steep gradients.
Latitude
Angular distance from any part of the earth measured north/south of the equator in degrees HORIZONTAL around the earth 0 degrees at the equator, 90 at the poles
How often should a landing be provided in a ramp?
At least every 40'
Difference between extensive and intensive green roof systems?
Extensive: shallow growing medium with drought tolerant plants only Intensive: deeper more organic soil with wider range of plants
Velocity (fps) of flow in a pipe
General rule: flow cannot exceed 15 fps or be less than 1.0 fps. Ideally it is between 2.0 and 7.0 fps. To increase velocity, reduce the size of the pipe or increase the slope. To decrease the velocity, increase the size of the pipe or decrease the slope.
Purpose of runoff control measures
Intended to intercept or control stormwater before it as an opportunity to concentrate or before it has reached sufficient volume or velocity to cause damage. Including diversions, waterway stabilization, slope protection structures, outlet protection
Water budget
One of the most important physical characteristics to figure out when building a constructed wetland. The balance of water in the system including inflows (precipitation, runoff, and base flows, such as streams), storage (surface and substrate), and outflows (evaporation, transpiration, percolation, and base and excess flows) = BALANCE OF WATER IN THE SYSTEM
Soils that are considered permeable
One that permeates more than 2.0 inches per hour, often loose sandy subsoils with little if any defined structure or restriction to movement of air or water. Slow permeability is 0.06 to 0.60 inches per hour
What type of foundation provides the greatest amount of grading flexibility and potentially the least amount of grading impact?
Pile/Pier Foundation
AWHC (Available Water Holding Capacity)
Soils available water holding capacity, to store in plant roots after excess water has left to saturated zones.
Well graded soils
Soils with a wide, fairly evenly distributed range of particle sizes. A well graded soil will compact better than poorly graded, but will not have as good of drainage as a poorly graded soil (sand)
Vertical roadway alignment
Safety relative to entering and exiting slopes
Two types of soil particles that are considered cohesionless
Sand & gravel
What type of compaction equipment to use for different types of soil
Sandy soils = vibratory steel drum fine sands & nonplastic silts = heavy rubber tire roller Clay soils = sheepsfoot roller (clay is easier to compact than sand)
Superelevation
The banking of a curved section of road to help overcome the effects of centrifugal force. Road surface is tilted inwards towards center of curve.
What type of soils are more subject to frost action?
Well graded soils Freezing causes movement of soil as it freezes and loss of bearing capacity as it thaws
A screen of dark, finely textured trees planted adjacent to a screen of bold, coarse textured trees, will result in what?
The fine textured trees will seem further away
Sieve Analysis
The grain size characteristics of soils that are predominantly coarse grained are evaluated by sieve analysis. Used mainly on clay or silt soils that expand and shrink due to moisture content. The higher the sieve #, the smaller the grain size: #4 sieve = 4.75 mm, #200 sieve = .075mm
Bearing
The horizontal angle measured from north to east or north to west, south to east or south to west. Cannot be greater than 90 degrees
On a dimensioning plan, how accurate should the final layout be?
The level of required precision is assumed to be 1/2 the smallest unit indicated.
Liquid Limit
The liquid limit of a soil occurs when a soil passes from a solid state to a liquid state with an increase in moisture.
Length of overland flow (feet)
The longest distance that water will flow in the watershed, because by the time this water gets from the farthest point on the watershed to the inlet point, the entire watershed will be flowing at its peak amount. This figure is used to determine the ToC.
Land Survey
The measurement of boundaries and/or area of a particular place or group of places. It includes: legal boundary surveys, positional accuracy, layout and staking to guide construction, field surveys to establish topographic or other land use maps
Slope of overland flow (%)
The percent of slope from the top of the identified watershed to the inlet into which the overland flow will drain. The steeper the slope, the more rapidly the water will flow to the outlet.
According to the principle of 'single statement', these items should not be placed in the drawings, but in the specifications
The quality and types of materials, the methods of installation, the expected results.
How are road swales generally graded?
To drain away from the road, at 2% or 3%
What is the purpose of subsurface drainage?
To maintain the water table at a level that provides desirable plant growth conditions and increases the usability of areas for recreational or other purposes. They remove only excess water, not that for plants, using perforated pipes. They are usually placed in areas with exceed pooling
Lateritic Soils
commonly develop in lush tropical rain forest, which have high temperatures and heavy rainfall
Tangential Road Crown
concrete, more noticeable centerline
Reverse Road Crown
depressed, runoff is not directed towards edges, used in alleyways
Mollisols
grassland soils with high base status. some of the most productive soils in the world, mid-latitude and prairie regions
Hardpan
layer of hard material just below surface preventing good drainage. this is an issue with foundations - often requires breaking through the hardpan layer as its bearing capacity may not be sufficient to support a foundation
Layout
location of the main elements of a project on the ground
Soil Podzolization
soil developed in humid, cold to temperature regions where vegetation produces acidic humus - coniferous or boreal forests podzolization happens where the decomposition of organic matter is inhibited and as a result, acidic organic surface layers build up. Under these typically acidic conditions, nutrient deficiency further hampers the microbial degradation of organic complexing agents
Aquilude
the impermeable beds above and below the water bearing bed in an artesian system
A construction contract is fully executed when?
work is complete and the owner has made the final payment
Installation of composite deck boards should be spaced apart at what amount?
3/16"
What is the maximum rise for ramps ranging between 12:1 slopes and 16:1 slopes?
30" maximum rise
Size of a township?
36 square miles
ADA Standards: clear width of walking surfaces
36" min. Where ADA route makes a turn, clear width should be 42" min. approaching the turn. 48" min. at the turn. 42" min. leaving the turn An ADA route with a clear width less than 60" shall provide passing spaces at intervals of 200' (at 60"x60" min.)
A curb height of 6" means the elevation of the top of the curb is always how much higher than the elevation of the road pavement?
6"
Optimal pH level for plants
6.0 - 7.5 above 7 is basic below 7 is acidic
How many acres is 1 square mile?
640 acres
Slope of an accessible ramp?
12:1 or 8%
What are 2 topographic factors that influence a site's potential for erosion?
(length x degree of slope) + soil structure = level of risk of erosion
Examples of sediment control measures
**To capture sediment before it can be transported downstream **Usually removed after construction, requires unclogging 1. Sediment barriers, filter strips for removing sediment from sheet or shallow flows 2. Sediment basin for settling sediment at concentrated flows 3. vegetative filters, storm drain inlet protection
Prepare erosion and sediment control plan
**focus 1st on mimicking the off-site transport of sediment and patterns and then how it will change as the site is developed 1. Location of sediment/erosion control fences on property edges or limit of construction areas 2. Hay bales in drainage ways, staking, types of bales (plastic or wire tied) 3. Seeding/strawing of soil storage piles (if unused for greater than 30 days) 4. Locate structure to prevent erosion from draining into sensitive ecological areas 5. Detention and/or retention basins: location, size relative to watershed served by basin, depth depending on amount of water and area available, shape: length vs width, top of dam and bottom elevations 6. Direction of drainage flow, with arrows 7. Setbacks from existing streams or wetlands 8. BMPs required by the National Pollution Discharge Elimination System (NPDES) Construction Activity regulations to meet Clean Water Act
How much capacity can an area drain handle?
1 area drain per 1,000 SF of paved surface A drain inlet does not include a sump
How much capacity does a catch basin typically handle?
1 catch basin per 10,000 SF of paved surface They are 2.5'-4' in diameter and the bottom basin is a sump or sediment bowl
Prepare grading plan
1. Calculating slopes: percentage, difference in elevation, length of distance, slope in percent or ratio 2. Contours (existing: dashed, proposed: solid), high side, low side, distance between contours indicates slope percentage, darken every 5th/major contour, indicate contour number on high side of contour 3. Finished floor elevation (FFE), always on interior of structure 4. Spot elevations on corners of building, outside foundation corners 5. Spot elevations (SE), high and low points, critical points 6. High point of a swale (HPS), prevent water flowing toward building or hardscape, direct flow toward drain inlet or stream generally 6" lower than FFE 7. Drain inlet: rim elevation, invert out elevation, invert in elevation 8. Step elevations: risers are generally 6", require SE at the top and bottom of a run of steps 9. Slopes of elements: min to max (hardscape min 1%, max 5%, softscape 2% generally min, 3:1 generally max), direction of water flow = perpendicular to contour, centerline of swale 10. Locate a dam for retention, detention, or storage of water 11. Roadways: slope, crown height (3",4",6",9"), curb height (6"), 12. Culverts: size of pipe, cover over pipe, invert and top elevations, slope of pipe 13. Surface drainage and calculations: amount of water calculated to detain or store, slope of land relative to speed of runoff, direction of flow perpendicular to contour, slope of pipe, cover over pipe 14. Subsurface drainage and calculations: pipe sizing (nomograph), slope of pipe, exiting and entering inverts with same or different pipe sizing), coefficient of friction, freeboard 15. Dams and weirs, configuration 16. Visual screening with landform 17. Pathways: slopes and as related to existing situation 18. Roadway location as related to min and max slopes
Prepare project sections and profiles
1. Completeness/accuracy/missing items?
Prepare a stormwater management plan
1. Identify watersheds relative to stream flow 2. Identify watersheds relative to localized runoff: roof runoff, pavement, turf, planting areas 3. Identify direction of drainage 4. Raingardens: configuration, plant materials, drainage 5. Roofgardens: identification of basic cross section, order of basic construction elements (waterproofing, geotextile, drainage, etc) 6. Protect sensitive wetlands or unique ecological areas or habitats 7. Bioswales: locate drainage structures to prevent drainage from reaching sensitive areas 8. Locate dam and size impoundment: quantity of storage, surface area and pool elevation, depth of storage
Prepare a demolition and removal plan
1. Items from existing conditions plan to be removed 2. Demolition processes: order of removal, items to be protected (trees, historic sites, buildings) 3. After removal site condition: erosion control
Prepare layout and materials plan
1. Locate building/structure from Point of Beginning/benchmark 2. Proper layout techniques, order of layout hierarchy 3. Dimensioning - various approaches 4. Types of materials used on a site, order of construction, reference to details **Grading plan establishes vertical position. Layout plan establishes horizontal position Fixed dimensions: ie legal property boundary Semifixed dimensions: ie sidewalks, walls Floating dimensions: +/- plant bed lines Field dimensions: after construction progress
4 site preparation steps for grading
1. Protection of existing vegetation and structures 2. Removal/storage of topsoil 3. Erosion & sedimentation control 4. Clearing & demolition, then placing grading stakes
Prepare general contract and bidding specifications
1. Public agency bid 2. Design bid documents 3. Permit submittal to a local agency 4. Order of basic components: notice to bidders, invitation to bid, bid instructions, general provisions, special provisions, supplemental provisions, technical specifications (CSI order), cover sheet with vicinity map and legal description, existing conditions map and surveys, layout plans
Prepare an existing conditions plan
1. Surficial geology 2. Soil types and capability: bearing capacity, permeability/infiltration rates, quality 3. Slope 4. Ridge lines and watersheds 5. Vegetation types, trees, save/remove 6. Property boundaries, bearings, point of beginning (benchmarks), coordinate systems 7. Easements for utilities, location, common width, function 8. Rights of way, location, function for the road 9. Waterways 10. Wetlands and wetland conditions, issues relative to runoff, erosion, relative to setbacks 11. Structures - grades and slopes 12. Utilities: water, electric, gas, telephone, sewer/storm/sanitary, fiber optic telecommunications, telemetry, data cable 13. Zoning/land use 14. Setbacks, property front and side boundaries, eco situations with drainage, wetlands, streams 15. Hardscape elements 16. Archaeological info, protection
Prepare a planting plan
1. Types of plants to use in context, performance: wet or dry conditions, soil type, safety/welfare, sight lines for automobiles, screening for safety, health/comfort for shade and wind 2. Plant ID - selection 3. Planting specifications: planting pit (size, depth, backfill), staking and guying with guy lines (approach, safety of guy wires/flags), time of year to plant
Station points along a road are what length apart?
100'
ADA Standards: max running slope and cross slope
1:20 max running slope (5%) 1:48 max cross slope (2.08%)
What is the maximum cross slope allowed on a sidewalk?
2% - range is 0.5%-2%
Design height of a driver from ground must be able to see an object in the roadway at ?? units.
2' ??
What is typical pipe coverage?
2.0 feet, for the entire length The headwall also must be tall enough to provide enough coverage here
Creating a right angle with the pythagorean theorem
3, 4, 5 method - with tape measurer, between the 3 and the 4 will be a right angle
How many square feet in 1 acre?
43,560 square feet
Traverse
A series of successive lines (often property lines) that are connected together. Ex: a calculation which begins at a known plot corner and utilizes the lengths and bearings of the plot description and ends at the point of beginning is known as a traverse
What is the point of origin of a relative grid on a site?
A site-specific point
Foundation surcharges
Additional loads other than the earth behind the wall (slopes, stepped terracing, structures, vehicular traffic)
Where do you place a filter strip?
Adjacent to impervious surfaces to intercept overland sheet flow, slow it down. Grass filter strips are used to trap sediment and protect the performance of other infiltration devices.
Point of no cut-no fill
All fill and cut matches/equals out and nothing is imported or exported
Two factors that affect the shear strength of a soil
Amount of internal friction and cohesion
Contour line
An imaginary line which connects points of equal elevation. All points on a contour line are at the same elevation. All contour lines are derived from a known point of elevation, with the zero elevation point being "Mean Sea Level".
Examples of outlet protection
Aprons, roughened surfaces, or shallow pools lined with rip rap at the end of a pipe or channel to allow energy of runoff to dissipate
What are property benchmarks?1
Base elevations that have been established while surveying. Any contours after this are determined based on comparison
Term for imported fill material
Borrow
Handrail Standards
Both sides of stairs and ramp Top gripping surfaces of handrails at 34" min and 38" max vertically above the walking surface
Prepare technical specifications
CSI format and order 1. General and procedural items: testing, quality control 2. Materials in order found in a typical CSI format set of specifications
When existing and proposed finished grade elevations are used instead of subgrade elevations, one must make adjustments:
CUT: proposed surface material increases the amount of excavation required and existing pavement/topsoil to be removed gross cut volume - existing surfacing material volume + proposed surfacing material volume = adjusted cut volume FILL: proposed surface material decreases amount of borrow required; existing pavement/topsoil being removed increases volume of soil to be placed gross fill volume + existing surfacing volume - proposed surfacing volume = adjusted fill volume
Parking Standards
Car spaces min 96" wide (8') Van spaces 132" wide (11') Accessible aisle should be min 60" 1 more accessible parking space required as you go up by 50 regular parking spaces
Stormwater Diversions
Channels that direct/intercept excess water away from areas where it is not wanted to areas where it can be appropriately disposed. Breakup sheet flow
Which soils are more cohesive?
Clay - sticks together Not cohesive = sand
3 Basic functions of any stormwater drainage system
Collect: analyze on and off site, where existing and proposed should go Conduct: open, closed, or combination systems of stormwater Dispose: outlet, influences method of conduction
Water Balance
Complete inventory of a landscape's hydrology , encompassing in a single view the interaction/behavior of all the landscape's water resources. Including surface runoff, infiltration, evapotranspiration, groundwater, and stream base flow.
Horizontal roadway alignment
Curve and super elevation relative to design speed of roadway. Avoid compound curves, incorporate sufficient intersection offset spacing, 150 feet. Superelevation is the slope of the road tilting inwards around a curve to counteract centrifugal force. On regular highway roads, usually a max superelevation of 10-12%. On roads with lots of ice/snow, the max is more like 8%. You can't go too high because then lateral friction will take over.
Is it less costly to have more cut or more fill?
Cut
A FILL situation is shown on a grading plan when proposed contours are drawn across existing in what direction?
DOWNHILL
Contours at the center of the roadway crown point which direction?
DOWNHILL
ID of a Drainage Area
Describe area where drainage begins (Area A)
Length of pipe in feet
Determined from center of inlet to the center of the next inlet or outlet
Procter Test
Determines the maximum density of a soil
Degrees of latitude and longitude
Divided into minutes and seconds with 60" in each degrees and 60' in each minute
Prepare site protection and preservation plans
EX: soil, existing features, existing pavements, historic elements, vegetation 1. This topic utilizes the existing conditions plan and the demolition plan, stating that particular items will be protected or preserved. Best management practices with regard to health, safety, welfare
RIM elevation
Elevation at grade for drainage structure subtract pipe coverage and pipe size to the get the entering or exiting invert elevation
Determine a pipe's invert elevation (IE) & invert elevation at outlet
Elevation at surface (minus) pipe coverage (minus) pipe size = Invert Elevation Pipe length x slope % = grade change at outlet Invert Elevation (minus) this grade change = Invert Elevation at Outlet
Northing/Easting
Geographic coordinate for a point Easting: the eastward measured distance from the x coordinate Northing: the northward measured distance from the y coordinate Township descriptions are started from horizontal and vertical lines called Northings and Eastings
Borrow Pit (Grid) Method for calculating cut/fill
Grid method, complex grading plans 1. Existing elevations are determined at each grid intersection by borrow pit leveling 2. Proposed elevations are determined at each intersection from the proposed grading plan 3. Take average of vertical difference at all four corners of a cell **Keep cut/fill separate when calculating 4. Volume is calculated by adding all the averaged values together, keeping cut/fill separate and multiplying by the area of one grid cell, then dividing by 27 to get cubic yards
Excavation backfilled with coarse aggregate stone
Infiltration Trench
Plane Surveying vs. Geodetic
Horizontal distances surveyed looking outwards, always measured on a horizontal plane. Distances recored on deed restrictions and surveys are horizontal. Geodetic = curvature of the earth is taken into consideration.
Slope Perception
Influenced by the texture of the surface material and the relationship to surrounding grades. The coarser the texture, the less noticeable the slope
Point of Beginning (POB)
In a metes-and-bounds legal description, the starting point of the survey, situated in one corner of the parcel; all metes-and-bounds descriptions must follow the boundaries of the parcel back to the point of beginning. Usually a Geodetic survey marker, building corner, survey monument, etc.
Benefits of soil compaction in construction
Increase in load bearing capacity, prevents soil settlement, reduces water seepage, swelling, and contraction. But this all depends on soil type!! 98% compaction isn't the same everywhere
Purpose of a check dam?
Increases infiltration, slows water, creates ponding that removes/settles sediment
Surface impoundment created by damming or excavating
Infiltration Basin ex: rain garden
Contour Area Method for calculating cut/fill
Large, simple grading plans. 1. Establish the no cut-no fill line 2. Separate the area of cut from the area of fill 3. Measure the horizontal area of change for each contour line within the no cut-no fill limit, keeping areas of cut separate from areas of fill (the area bounded by same numbered existing and proposed contour lines) V = i (A1 + A2 + A3...) A1,A2... = area of horizontal change for each contour in SF i = contour interval in feet 4. Multiply the total areas by the contour interval 5. Divide by 27 to convert to YD3
Average End Area Method for calculating cut/fill
Lineal construction, paths, roads, utility trenches. The volume of cut (or fill) between two adjacent cross sections is the average of the two sections multiplied by the distance between them. The shorter the interval between the sections, the more accurate the estimate will be. The sections are usually exaggerated by 5 or 10x. V (cubic feet) = [(A1 + A2) / 2] x L short distance between A1+A2 makes more accurate estimate
List 3 types of soils that are typically avoided/removed when identified on a project site
Loose silt/sand, peat/organic, soft clays/water loaded clays
ADA standards: ramps
Max running slope of 1:12 (8.3%) Max cross slope of 1:48 (2.08%) Min clear width: 36" (between handrails) Max rise of a ramp: 30" Max length: 30' (@ 1:12) Landings at the tops and bottom at 60" min. length At change of direction 60"x60" clear landing
What is the minimum a grass swale should be designed for?
Minimum peak flow of a 10 year storm q = AV flow = cross sectional area of flow x velocity of flow
Stormwater Conveyance
Moving of surface water across the ground and with pipes
Does structural soil want mid-range sized particles? What is a typical structural soil composition?
No, it should be gap graded - to support paving or load, and create gaps for topsoil to be added Mix of gap-graded angular crushed stone, clay loam soil, and hydrogel as a binding agent
Most general conditions would require a contractor who recognizes a deficiency violation in CDs to what?
Notify the landscape architect in writing
Open vs. closed drainage system
Open: all surface runoff from paved and unpaved areas is collected and conveyed on the ground, primarily by swales. Then discharged to management location. Closed: Surface runoff from paved and unpaved areas is collected at surface inlets and conveyed by underground pipes to an outlet either on or off the site.
Where do you use bioretention?
Parking lot islands, planting strips, and swales are used to collect and filter storm runoff. Through the use of grass filters, shallow ponding, infiltration, and plant uptake, this technique takes advantage of an underutilized portion of the landscape for water quality enhancement. Bioretention swales, cells, rain gardens, filter strips
Slope of pipe in percentage
Pipe is generally designed to be placed at a minimum slope of 1%. There is no limit on the maximum size as long as the maximum velocity is not exceeded, but you usually start at 1% when testing it out. **At a slope of less than 1%, it is required that the pipe be sized up by one size (a 12" pipe bumped up to 15")
Cut-off drains
Pipes placed across a slope to intercept water that would otherwise be forced to the surface by an outcropping of an impermeable layer, such as a tight subsoil
Ericaceous plants
Plants that require acidic soils. Most plant material will not tolerate excessively wet soil because water displaces air
Support posts for playground equipment used in areas at sub-zero temperatures, should be made of what?
Powder coated steel
Daylighting a road curve
Providing a clear sight distance
Requirements for bidding of a public project
Public advertisement, a bid bond, payment of prevailing wage rates, insurance covering liability and property
Prepare construction details
Questions relative to example construction detail: 1. Wood: treated, nontreated, span of the elements: beams, post, joists, decking 2. Metal: iron, steel, aluminum 3. Concrete: finish, strength, reinforcing, depth, frost depth 4. Masonry units: concrete block, brick, precast retaining units 5. Paving: precast, cast in place 6. Size of the materials 7. Connection of elements: wood to wood, wood to concrete
Specific Gravity of soil
Ratio of the weight of the soil solids to the weight of water in the soil, used to calculate the density of the soil solids (usually 2.5 - 2.8, with 2.65 as typical)
Contours that point in an uphill direction indicate what?
Ravine or valley. When they point downhill, this indicates a ridge line.
How do retention and detention basins ameliorate water quality?
Retention: (wet) additional volume is provided for the settling out of sediments Detention: (dry) may have a small orifice at the bottom of the outlet structure so that runoff from frequent storms, which tends to flush contaminants into the pond, is retaining for a prolonged period
Hachures
Slashes on closed contour lines indicating a depression.
How does slope orientation affect erodibility?
Slope orientation may influence the ability to reestablish a protective vegetative cover
How much bearing capacity is needed for a point load of 6 tons?
Soil bearing capacity of 2000 lbs per square foot with a footing of 6 square feet. Because 6 tons = 12,000 pounds = 12,000/6 = 2,000
What is a cistern?
Storage structure connected to roof drains for a rainwater harvest system
Differential settlement
Structural failure due to unequal settlement. When part of a building is on compressible stratum and the rest of the building is on firm soil strata.
Examples of slope protection structures
Structures that convey runoff down steep slopes through pipes or chutes
Cut/fill volumes are determined using which level of grade?
Subgrade, not finished grade so therefore you must adjust
Method of sizing storage for detention or retention ponds using the modified rational method
Subtract the volume of outflow from the basin from the inflow volume to the basin for the same duration. The difference is the required storage.
Littoral Drift
Term used for the transport of non-cohesive sediments, mainly sand, along the shore face due to action of breaking waves.
Soil Shear Strength
The ability of soil to withstand loads. Test for this? Atterberg Limits test
Magnetic declination
The angle between magnetic north and true north. On an east declination magnetic north is greater than true north. Magnetic north based on the earth's magnetic field, changes often
Soil Angle of Repose
The angle in which a stacked soil begins to slip/slope. Cohesive soils (like clay) need flatter angles when stacked higher. Sand and gravel (with high internal friction) do not - their angle of repose does not decrease when height increases.
Longitude
The angular distance of any point on earth measured east/west of the prime meridian 69 miles apart at the equator
Atterberg Limits
The arbitrary limits which define the boundaries between the different states of rigidity or fluidity of FINE GRAINED SOILS. It may appear in 4 states: solid, semi-solid, plastic, and liquid. This test is used in the preliminary stages of building any structure to ensure that the soil has the correct amount of shear strength.
Azimuth
The clockwise angle from the north end of the reference meridian line to the line in question, horizontal, as an angle between 0 and 360
Coefficient of runoff (C)
The coefficient which determines the amount of water that will flow from a surface area as opposed to that which will soak in. A list that depends on different materials. Drainage coefficient = the depth of water removed over the drainage area in 24 hours
Roughness coefficient (c)
The roughness of the interior of a pipe is considered a Coefficient of Roughness (n) and must be figured into the pipe sizing equation. A standard concrete pipe is n=0.013. The "Nomograph for Circular Pipes Flowing Full (Manning's Equation)" takes this roughness number into account.
Thermal Attenuation
The soil cools the runoff
Bioretainment
The storage of stormwater on the various surfaces of a planting.
Soil Bioengineering
The use of live, woody, and herbaceous plants to stabilize or protect stream banks, shorelines, drainageways, and upland slopes. Goal is to prevent or minimize slope failure and erosion, with live staking, live fascines, brushlayering
Vertex
The vertex of an angle is the point where two line segments meet or cross
Q (cfs)
Total discharge in cubic feet per second per watershed or drainage unit. This is the volume used to size pipes in the drainage system.
A CUT situation is shown on a grading plan when proposed contours are drawn across existing in what direction?
UPHILL
Contours at the center of a swale always point which direction/
UPHILL
USCS soil classification vs. ASSHTO
USCS - described texture and grain size, used in engineering and geology ASSHTO - also soil classification, used in road construction
Surficial geology
Underlying geological situation relative to any expected land use
Lifts
Uniform layers of fill spread to a specified thickness, each layer compacted
Frost Heave
Uplift of the soil surface or foundations caused by freezing of moisture in the soil.
Landscaping practices that are part of stormwater BMPs
Vegetated swales, filter strips, basin landscaping, urban forestry
Construction techniques for managing shoreline erosion?
Vertical revetments (wave breaks at shore), breakwaters, sloped revetments, beach renourishment
Sizing Storm Pipes: How much lower should the Invert Out elevation be from the Invert In elevation?
When they are like-size pipes entering and exiting the same man home or drain inlet = .1 or .2 lower When they are NOT like-size pipes entering and exiting the same man hole or drain inlet, the elevation of the Invert Out will be the difference in elevation between the two pipes
When is a manhole typically used?
Where there are changes in size, slope, or direction of underground pipes. It is more cost effective if catch basins and manholes are combined
ADA standards: when does a ramp require a handrail?
With a rise greater than 6"
Utisols
moderately leached soils of temperate, humid climates. subsurface clay condition, 35% base saturation, dominant soils of much of the southeast US
Parabolic Road Crown
rounded, asphalt
Soil Bearing Capacity
the ability of the surface and subsurface material to carry the weight of the structures, without yielding or displacement. The capacity of the soil to support loads applied to the ground.
Shear Resistance
the resistance of soil to movement when pressure or impact is applied. Occurs from the friction between the soil particles as they slide by one another. the HIGHER the shear resistance, the greater the compactive force required CLAY = high resistance SAND = low resistance
