Lesson 2: Site Assesment & Site Work Flashcards
Comfort zone for humans
65-75 degrees with 30 - 60% humidity
Ideal orientation for northern hemisphere is?
Slightly north of south
Benefits of large glazing towards south is?
Great for winter heating, but cause issues in summe
Properties of east and west exposures
Low morning and evening light and can be difficult to shade.
Fenestration should be kept to a minimum
Benefits or northern exposure
Least amount of solar radiation, most even light
Max solar angle is?
June 21 - summer solstice
Lowest solar angle is?
December 21 - winter solstice
Median solar angles are?
March and September 21 - vernal and autumnal equinoxes
Where is heat transmitting greater through walls?
Northern hemisphere. Lower sun angle
Where is heat transmission greater through roofs?
Southern Hemisphere. Higher sun angle
What are some solar shading strategies?
Floor overhangs
Roof overhangs
Fins
Lovers
In the northern hemisphere, deep horizontal overhangs are most effective for which exposure?
Southern
In the northern hemisphere, deep vertical fins are most effective for which exposure?
East and west
Low buildings are effectively shade by which kind of tree for its southern exposure?
Deciduous
What are the benefits of shading with a deciduous tree on the southern exposure?
Allows winter solar radiation, but blocks undesired summer solar radiation
What are summer of the benefits or placing trees on site?
Interrupt winter winds
Reduce noise
Reduce glare
Privacy
Where do the highest winds speeds occur in the N. Hemisphere?
Gulf and Atlantic coasts
Wind load increase when building ____ increases.
Height
Wind pressure is measured in?
Pounds/sq in
Wind pressure varies as the _______ of the wind velocity (mph)
Square
Wind velocity and direction have an effect on which building system?
HVAC
What kind of glazing can be used to mitigate undesired heat gain?
Multiple glazing
Heat transmission is expressed by?
U factor
The R factor is the inverse of the______?
U factor
The # of BTU’s passing thought 1 sqft of wall or roof assembly when the temperature difference between inside and outside is called the_____
U factor
True or false: A low U Factor indicates rapid heat gain/loss
False
Heavy materials have a high________
Thermal inertia
Cost of heating is relative to variation between ______&______ temps
Outside and inside
What are ways in which water is used on site?
Irrigation
Moderating microclimate
Sense of excitement and tranquility
Sound can mask urban noise
Benefits of water on site?
Increase property desirability and raises property value.
True or false: An onsite body of water should be altered
False. It should be left in its natural state if possible
To prevent onsite body of water from flooding, what should be provided?
Swales and ponds
A body of water flowing in a channel is called a_________
Stream
What are some materials used to reinforce the waters edge?
Concrete and stone. Both with gravel backfill
At which area of a stream should bridges be placed?
At the narrowest point to reduce span
Water falling from because of changes in elevation is called a ________
Waterfall
The natural process or water evaporation, absorption and precipitation is called the ______________
Hydrolic Cycle
Most water that falls via precipitation is either _________ into the atmosphere or is _________ by plants
Evaporates or absorbed
_________ is the process by which water soaks into the ground
Infiltration
Water flowing off of land is termed as _________
Runoff
Runoff is the total of precipitation - ___________ - ____________ - ___________
Evaporation, infiltration , transpiration
We are most concerned with which parts of the hydrolic cycle when site planning?
Runoff and infiltration
Which factors contribute to the increase of runoff when developing a site?
Removal of vegetation - less transpiration
Pervious land replaced by impervious surfaces - less infiltration
Runoff can enter the drainage system and be held in ________ to decrease the chances of flooding
Detention ponds
To create an amount of runoff of the developed site equal to that which existed prior to development is the main purpose of which site feature!
Detention pond
What is a great strategy for naturally filtering the water that enters a detention pond?
Line its banks with wetland vegetation
True or false: Urban development as no impact on runoff
False. It has a major impact on runoff
Flat land where streams flow is know as a ________?
Floodplain
Design for a 10 or 100 year flood requires design floor levels which are ________ the stated levels
Above
Development in a floodplain should be limited to _________?
Open space or low density, elevated housing
True or false: The water table in a floodplain usually occurs at the surface
True
True or false: Soils subject to drastic volumetric changes when when are suitable for building
False
A suitable way of dealing with the potential for flooding is to introduce __________
Concrete flood channels
The amount of underground water is _________ than the amount found in lakes and streams
Less than
Underground water is created by which method of the hydrolic process?
Infiltration
The region where the space between soil grains contains water and air is know as ___________?
The area of Aeration
The lower region where the void space is completely filled with water is known as the ______
Area of saturation
Factors of climate
Range of temperature Hours of sunshine Velocity and direction of wind Precipitation Humidity
The surface boundary between the area of Aeration and Saturation is known as the ___________
Ground water table
Construction excavations must be braced pumped dry if the water table is less than ________ below the surface.
6 feet
Basements in areas with a high water table must be designed to be __________ with walls that can withstand ____________
Waterproof
Hydrostatic pressure
Soils in areas with high water table usually results in a __________ bearing capacity
Reduced
Underground permeable material through which water can flow is known as an _________
Aquifer
Which kinds of plants are easier to maintain?
Indigenous
True or false: Trees and shrubs can create a vertical sense of enclosure.
True
True or False: Closely spaced trees do not create a horizontal sense of enclosure.
False
True of False: Trees and shrubs can be used to create privacy screening
True
What are some of the environmental benefits of having trees onsite?
Block wind and sun Cools, humidifies and filters air Creates sheltered zone from wind Can control erosion and destructive runoff Absorb sound Provides habitat
What is a great way of utilizing ground cover such as pavers or gravel beds?
To define space
What dictates the stability of a building in relationship to site?
Soil composition
The chemical decomposition of rock, introduction of water and air, and decay of vegetation and animal matter creates what?
Soil
The solid material that forms the earth’s crust and is the strongest for foundations is?
Bedrock
Fine textured, soft rock is known as?
Slate and shale
Rocks detached from bedrock is known as?
Boulders
Disintegrated rock masses that use to be solid is known as?
Decompressed rock
A consolidated mix of gravel, clay and sand that is good for foundations is called?
Hardpan
Loose granular rock pieces that are between .002 and 1/4 inch in size is known as?
Sand
Fine granular deposits from running water that are .002 inches or less in size is known as?
Silt
When mixed with water, silt becomes _______
Mud
Fine grained, firm and cohesive by the decompression and hydration of rock that expanse and contracts when wet is called?
Clay
Which type of soil is the most unpredictable and least stable for supporting building foundations?
Clay
A mix of sand and moving water and is totally unsuitable for building is called?
Quicksand
Who orders a subsurface exploration?
The architect
A simple excavation that allows visual inspection of the soil conditions is called a________
Test pit
A test by which a platform is erected on site and loaded consistently to observe settlement is called a _____
Soil Load test
The process by which samples are drilled by means of an auger is know as?
Boring
Boring by means of a water jet is known as a _______
Wash boring
What is a major disadvantage of wash boring?
Produces a mixed sample
What is a major benefit to wash boring?
Can surpass 100 feet
Boring by means of a diamond drill that can penetrate all soil materials but is more costly than other methods is know as?
Core boring
Boring done by means of driving a split ended pile every 5 feet is known as?
Dry sample boring
Who performs the analysis of the soil samples?
The soil engineer
What are some of the properties of soil giving in a soil report?
Specific gravity Grain size Grain shape Liquid and Plastic limits Wet content Void ratio Unconfined compression
___________ occurs when dead load is added to a structure which compresses the soil underneath the foundations
Settlement
True or false: Slight amount of settlement is a major problem
False. It is of little concern and is expected
What type of settlement cause serious cracking and failures?
Differential settlement
True of false: Settlement should be constantly monitored during construction
True
The freeze/thaw cycle which can have a significant impact on foundations and impart greater stress such as heaving is known as?
Frost action
Frost action is dependent on which two factors?
Soil type and geographic location
The level below which no freezing occurs in the soil, thus the area below which the foundations should be placed is known as the ________?
Frost line
True or false: Earth movement is prefers to near the surface due to fluctuations in moisture content
True
Earth movement due to fluctuations in moisture are slight at a depth of ________ feet
5
The level below which the ground is completely saturated with water is known as the __________?
Water table
Pipes used to divert water away from the building foundations are known as?
Drainage tiles
Drainage tiles are usually placed where?
6 inches below lowest floor slab
Slabs on grade are subject to hydrostatic pressure and are usually placed on top of a few inches of gravel to prevent what?
Capillary action
What are some methods of draining the site?
Grading contours of site
Gutters
Berms
Sloped paving
Bearing capacity can be increased by _______ the bearing area of the footings
Increasing
Another method of increasing bearing capacity of soil is by _________ it
Draining
Is solid is good soft or contains organic fill, it should be removed and replaced by ____________
Compacted granular material
Existing soil can be covered with a porous layer of sand, gravel or rushed rock, mixed together to form _____________
Hardpan
To reduce void volume to increase bearing capacity one can add a compaction layer, use subsurface drainage or uses ________
Piles
Soils can be compacted using _________?
Machinery
True or false: Site analysis must be done to see which part of the site is suitable for certain functions. ie: the location of building or location or road.
True
_________ & _________ must be balance with the expense of importing and exporting soil
Cut & file
Onsite drainage should connect with what?
The natural drainage system
The design of drainage patterns is known as?
Surface water management
The design of _______________ is determined by the amount of run off, which is determined by the duration & intensity of storms plus the soil characteristics of the area
Surface drainage system
Surface drainage system is based on ______, _____, ______, ______ year storms
5, 10, 25 and 50
The basis of surface drainage system (SDS) for a residential area is typically the ______ year storm
5
The basic of design for the SDS for a heavily developed area is usually a _____ or ______ year storm?
25 or 50
Water flowing as a sheet across surface is known as a _______ _______ system
Sheet flow
Gutters and underground pipes are part of what kind of system?
Drainage system
Water will flow as a sheet across a surface at ______ to _______% slope
0.5 to 1
Land adjacent to building should be sloped at ___% minimum to facilitate drainage
2%
The banks drainage ditches are usually sloped between _____ and ____%
2 and 10%
Grassed slopes should not exceed ____%
25
Unmowed ground cover (ivy) should be slope at a maximum of ____% to avoid erosion
50%
To avoid erosion, surface drainage should be contained in _________
Channels
Subsurface drainage conduits should be sloped a minimum of _____% to be self cleaning
0.3%
True or false: surface drainage is more expensive than underground drainage
False. It is much cheaper
Subsurface drains with open joints allows for what?
Soil to drain
Drainage lines are usually made _____ or ______
Clay or pvc
A level slope is less than ____% and is suitable for all building
4%
An slope between 4 to 10% is known as an ________ slope
Easy
At steep slope is any slope greater than ____%
10
Steep slopes lend themselves to what kind of design?
Split level
The max slope for a grass recreation area is _____%
3%
Walkways adjacent to buildings should be slope at less than ____%
4
Parking areas should have a max slope of ____% for drainage
5
Vehicular streets should be slope at a max of ___% for drainage
10%
The surface features of an area is know as its_________
Topography
__________ denotes a particular elevation
Contours
The change in elevation between two contours is know as a _________?
Contour interval
Hilly terrain has a _________ contour interval
Higher
Smaller scale makes will have a ________ contour interval for legibility
Higher
What is the formula for calculating gradient (G)?
G = V \H * 100
Gradient is expressed as a ________
Percentage
Removal of existing soil to allow for construction of foundations and substructure is known as _________
Excavation
Permanently cut slopes should not exceed a ______ to ______ slope
1 to 1.5
Permanently filled slopes should not exceed a slope greater than ______ to _______
2 to 1
About how much does 1 cubic yard of soil weigh?
1 ton
The alteration of site contours is known as ______
Grading
The addition or removal of earth prior to construction is know as _______
Rough grading
The final distribution of earth at the end of construction heat is more precise and includes top soil is know as _____
Finish grading
Finish grade is accurate to within a margin of error of _____ inch
1
The replacement of earth around foundations or retaining walls after for work is removed is known as________
Backfill
Backfill is usually deposited in _____ to ______ inch layers, tamped and compacted to avoid settlement
6 to 12
What transmits the building load to the underlying soil?
The foundations
Parts of the foundations that have been widened to spread the load over a wider area is known as__________
Footings
Foundations for soil close to ground with adequate bearing pressure are known as _________ foundations
Shallow
Square or rectangular pads of concrete that spread column loads over a wider area are known as _________ footings
Column
A continuous spread footing under a wall is known as a ______ footing?
Wall
When column footings abut a property line, the exterior column connects to the first interior column. This is know as a _________ footing
Combined/cantilevered footing
One large footing beneath an entire building used when soil conditions are poor is known as a ________ or raft footing
Mat
What is similar to a mat footing, but the weight of the soil removed equals the load of the building?
Boat footing
What are the types of shallow foundations?
Column footings Wall footings Combines/cantilevered footings Mat footings Boat footings
When upper soil has inadequate bearing capacity what type of foundations are used?
Deep foundations
What is used to transfer loads to firmer, deeper soils?
Piles
Load being transferred from building to soil by contact between pile and surrounding soil is known as ______ _______
Skin friction
When the buildings load is supported directly by the rock or subsoil under the pile’s tip is know as _________ ________
End bearing
Piles are usually made of…..
Wood
Concrete
Steel
Composite
A drilled vertical shaft that is filled with concrete that transfers the load via skin friction is known as a ______ _______
Drilled pile
A drilled vertical shaft filled with concrete which transfers the load by end bearing is known as a __________ _________
Drilled caisson
Box like foundations used in very wet, soft soils are known as _______ and _________
Caissons and cofferdams
Caissons and cofferdams are usually formed from….
Timber
Steel sheets
Concrete
Excavation usually takes place where in relation to a caisson?
Inside
For bridge piers or similar structures in water, the are is usually surround by watertight steel sheets which is known as ______ ______ , water is pumped out and foundations are then constructed. This method is known as ___________.
Sheet piling
Cofferdaming
What are the common methods of providing support for existing foundations or earthwork?
Sheeting, bracing and underpinning
Temporary walls of wood, steel or precast used to retain surrounding soil around an excavation is know as ______
Sheeting
A type of sheeting by which a narrow trench is excavated and filled with slurry and then filled with rebar and concrete as the slurry is pumped out is know as a _______ ________
Slurry wall
When the sheeting is braced to resist earths pressure is know as ______
Bracing
What is a type of bracing?
Raker
What is the drawback or using a Raker?
It interferes with excavation. If possible, the sheeting should be tile back into existing soil
Supporting existing foundations and walls which are being extended downwards is known as _______
Underpinning
What are some common methods of underpinning?
Needle beams and pipe cylinder with hydraulic jack
Roads, walkways, fences lighting and landscaping are known as ________ ________
Site improvements
Bituminous paving product made of asphaltic petroleum that is applied hot or cold over a prepped foundation in a single layer is known as ______ ______
Asphalt paving
What are the layers for paving listed from top to bottom?
Asphalt 2-3 inches thick
Tamped fine aggregate
Tamped coarse stone or gravel
True or false: grading of paving is crucial to avoid ponding
True
Type of asphaltic paving which consists of asphaltic cement and graded aggregates that are mixed in a plant and applied while hot is known as _______ ______
Asphaltic concrete
Type of asphaltic paving that is the same as asphaltic concrete except applied as a cold liquid is known as _______ ________
Cold laid asphalt
Crushed stone, gravel or slag base compacted to a smooth surface that is then sprayed with hot asphalt cement or asphalt emulsion that is covered by fine aggregates and rolled until the aggregate filled the voids is known as ___________
Asphalt macadam
What are some other common paving materials?
Brick
Cobbles
Granite sets
Flag stone
What kind of paving is durable for pedestrian traffic and is usually laid over a sand or sand/cement bed
Brick paving
What kind of paving is best as an alternative to asphalt that consist of rounded river stones 2-4 inches in diameter?
Stone cobbles
What are small, rectangular or square stones set in cement or mortar?
Granite sets
What is a thin slab of slate, blue or soap stone that is installed over a sand or mortar bed on top of a concrete slab?
Flag stones
When earth is shaped or retained to to modify finished grade, it is known as a _______
Grade change device
What are types of grade change devices?
Retaining walls
Stone riprap
Cribbing
The development of outdoor space using earth, rock water, plants and other devices is known as _______
Landscaping
One should take care to preserve what during the development of landscaping?
The existing vegetation
When design landscaping one should consider the following:
Suitability Visual effect Future growth pattern Spacing Overall pattern
What are the benefits of onsite vegetation?
Filters sunlight and controls radiant heat from ground Reduces wind and noise Absorbs light energy Reduces wind speed Reduces daytime temps
How much light energy can vegetation absorb?
Up to 90%
By how much can wind speed be reduced by vegetation?
To as low as 10%
By how much can the daytime temp be reduced by vegetation?
15 degrees
An architect must analyze ________ and _______ conditions and evaluate alternative ________ _________ in order to recommend optimum location for structures to minimize site work costs
Slope and soil conditions
Building sites
The architect must also review the cost of various ______ ______ and select the most cost effective system
Surfacing methods
The owner may establish the scope based on __________, _________ and __________.
Anticipated need
Quality of materials
Total budget
If the project runs in to budget issues because the owner insist on using a specific material, what must he architect insist upon?
Reducing the quality of the material or suggest a compromise using the desired material and a cheaper material
What must also be factored in for site development cost?
Continuing maintenance
The relative cost and long term benefits of a system may need to be evaluated. If so’ evaluate the following:
In a 30 year life cycle of a building. If product A cost $1 and has a life span of 5 years and product B cost $2 and has a life span of 15 years, which is cheaper?
Product B. Product A would have to be replaced 6 times at a cost of $6, where as Product B would have to be replace 2 times at a cost of $4 over the life span of the building
Site work may include:
Demolition of existing building and site improvements Earthwork Foundations Utilities Paving Lighting Site furniture
The cost of labor and materials, contractor efficiency, technology, site characteristics and development usually effects _______ cost.
Initial
The cost of maintenance over the course of several years effects _______ costs
Long range
If product A cost $8 and has a life span of 5 years, but product B cost $10 with a life span of 10 years, which has the lowest annual replacement cost if 100 sqft of material is needed?
Product B
Product A is $800 over 5 years = $160 annual replacement cost
Product B is $1000 over 10 years = $100 annual replacement cost
What are some strategies for cost control relative to site work?
Locate building on gentle slope
Arrange vehicular traffic along natural site contours
Locate paved parking on relatively level ground
Locate building close relative to new and existing utilities
Select indigenous plants
Avoid high water table
Use appropriate building materials
When and where was the first zoning ordinance enacted to prevent streets from becoming dark canyons because of skyscrapers?
NYC 1916
What recognizes aesthetic, environmental problems and preservation of historic sites as planning and development factors?
Model land development code
What was a common practice in NYC to allow developers to create taller buildings?
Adding a public plaza in front of the building
What are some of the factors dictated by the zoning code?
Building height Location of building on site Size of building Setbacks Off street parking Percentage of building coverage (FAR)
Land coverage is expressed as a _________.
Percentage
Floor area ratio (FAR) is calculated as what?
Total usable floor area divided by the total site area
The FAR restricts what?
Building bulk
Off street parking requirements usually require the owners to provide what?
Certain amount of parking spaces per visitor/tenant
In what ways can parking requirements be expressed?
Number of a spaces per unit
Number of spaces per usable floor area
What is a type of zoning developed to overcome rigid traditional zoning and make regulations relative to the changing patterns of development?
Flexible zoning
An exception or deviation from an ordinance grandad by zoning board is known as a ______
Variance
Flexibility in an ordinance granted by a zoning board only when certain conditions are met in the public interest is know as __________ . This does not change the zoning designation for the site
Conditional use
Reassignment of the zoning designation of a parcel is know as _______
Re zoning
When the developer agrees to extra restrictions in order to be granted a conditional use it is known as __________.
Contract zoning
Rezoning small individuals parcels is known as ________.
Spot zoning
Agreeing to waive certain requirements in an effort to reward builders for providing bonus features that benefiting the community is know as _______ or ________ zoning
Bonus or incentive
