PA/PPD Site Development: Soil-Drainage-Foundation

Types of boring tests

Auger borings Core borings Wash borings Dry sample borings

How to divert subsurface water away from a building's foundation

Drain tile/French drain (perforated pipe) system

Permeability

Drainage rate

Overconsolidated soil

Historical compression (soil memory)

Common soil problems

Inadequate bearing capacity Subsurface water Shrinkage Slippage Seismic forces Frost heave

Excavation slope support systems

Shoring Slurry walls

Foundations and underconsolidated soil

Short and long term settlement

Grass slope parameters (drainage)

Should not exceed 25%

Soldier beams and lagging

Steel columns (soldier beams) driven into earth with lagging (wood planks) fastened to it.

Runoff

Storm water that does not seep into the ground Must be drained away from buildings, roads, and other areas of activity

Gravel

Particles over 2mm in diameter Excellent for construction loads, drainage and sewage drain fields Unsuitable for landscaping

Clay

Particles under .002 mm in diameter. smooth and floury when dry, plastic and sticky when wet Expansive = poor for foundations High porosity/low permeability = poor drainage = bad for landscaping and drain fields High porosity Low permeability

Pile caps

Thick reinforced concrete blocks that distribute the load from the column to the (deep) foundation.

Waterstop

Used between the slab on grade and the foundation wall to seal the joint against water penetration Rubber/neoprene

Specific gravity (soil)

Used to determine void ratio

Water table

The level below which all soil is saturated with groundwater

Abrasion resistance grades (pavers)

Type I Type II Types III

Factors to consider when designing footings

Unit loading Shear Bending

Deep wells (dewatering)

Used to lower water table more than well points (100' or more). ACTIVE.

Benched excavation

Utilized when site is larger than the area to be covered by the building.

Soil bulk density

Weight/volume of any unit of soil

When to use testpits

When foundation is not expected to extend deeper than 16'

Characteristics of PVC pipe

Widely used High strength Lightweight Low cost Easy to work with Durable Nearly all wastewater sewers Environmental concerns in manufacturing Difficult to recycle

Typical pile materials

Wood Steel Concrete Composite

BEES model evaluates what 10 impacts

global warming potential acidification potential eutrophication potential (excess nutrients) natural resource depletion indoor air quality impacts solid waste impacts smog ecological toxicity human toxicity ozone depletion

shear resistance

resistance to sliding

Aeolian soils

transported and deposited by wind Typically silt or sand-sized soils

Infiltration trench (characteristics)

2' - 10' deep (depth to be coordinate with bedrock/water table) Trench is lined with filter fabric and stone Observation well should be installed in trench to monitor sediment and dewatering Idea for small drainage areas

Infiltration basin

A depression used to detain stormwater for short periods of time until it percolates to the groundwater table (similar to detention basin) Suitable for larger drainage areas and water is stored in a visible surface pond Offsets the increase in runoff from the developed site Designed according to infiltration trench parameters

Radon

A naturally occurring radioactive gas

Construction of needle beam support

A series of holes (5 - 10') apart are made in wall. Steel beams are placed thorugh them and supported on mud sills or blockings.

Brownfields

Abandoned or underutilized properties that are contaminated or perceived as being contaminated

Types of dampproofing

Admixtures Bituminous coatings Cementitious coatings Membranes (typically used for waterproofing) Plastics

Design strategies when water soluable pollutants are at risk

Algae in wet ponds Microorganisms in wetlands Biorentention beds Rain gardens

Steps to restore vegetative cover (landscape restoration)

Allow for soil analysis Select plants that will stabilize and revegetate, must be able to reestablish quickly Add acrylic polymers to soil Sod can sometimes be utilized Use trees for long term success

Grading

Alteration of a site's contours.

Examples of vapor barriers

Aluminum foil Sheet plastic Asphalt saturated felt

Soil porosity

Amount of pore space in a soil Relates to grain size distribution and consolidation

Relative humidity

Amount of water vapor air contains/maximum it can contain

Formaldehyde

An air pollutant that is a colorless chemical used to manufacture building materials and many household products, such as particleboard, hardwood plywood paneling, and urea-formaldehyde foam insulation.

Drain inlet

An opening in the ground that allows stormwater to run directly into the storm sewer; opening is covered with a metal grate

Catch basin

An underground reservoir that has a sump built into it. Debris settles into the sump instead of flowing down the sewer

Damproofing

Applied to a foundation wall when hydrostatic pressure from the groundwater table will not occur Typically applied in liquid form (brush/spray) Applied to each contacting surface of foundation Used below grade

Wetlands (characteristics)

Areas inundated/saturated by water often enough and long enough to support vegetation that has adapted to this condition Great deal of biodiversity 18 - 24" of saturation

Characteristics of liquefication

Associated with earthquakes Soil loses bearing capacity Fine and medium grained sands, silts in loosely packed layers Denser the soil, the lower the liquefication risk

Sources of asbestos

Attic and wall insulation Vinyl floor tiles and backing Roofing, siding, shingles Textured paint and patching compound Walls/floors adjacent to wood burning stoves PIpe insulation Oil and coal furnace gasketing

Methods of mitigating liquefication in seismic zones

Avoid locations where potential for ground failure has been identified Compact the soil Change the soil Dewater the site

Methods of measuring building performance

BEES model (EPA and HUD) ASTM LEEd

Health issues caused by lead exposure

Behavioral/learning problems Hearing problems Anemia Cardiovascular issues Increased blood pressure Decreased kidney function Reproductive issues

Sources of formaldehyde exposure

Breathing in off-gassed formaldehyde

Well points (dewatering)

Can lower water table 15' (less than deep wells) vertical pipes with screen openings inserted into ground and water pumped away from construction site. PASSIVE

Health issues caused by dioxin exposure

Cancer Reproductive issues Developmental problems Compromised immune system

Concerns with treated lumber

Cannot come in contact with people, animals or groundwater Disposing of treated lumber is difficult Not waterproof, guards against insects only

Permeable (watertightness)

Capable of being penetrated by water without causing rupture or displacment

What determines bearing capacity of soil

Code Testing

Storm drains

Collect water from roof downspouts, drain inlets, catch basics and drain tiles surrounding the building foundation

Waterproof

Completely impervious to water, whether under pressure or not

Rainwater collection system

Composed of a water collection system, storage cistern and a water distribution system

Impact of increased dead loads on structure on soil

Compresses soil beneath footings >> reduces void volume >> settlements

Popular materials for pond construction

Concrete Geotextiles Plastics Fiberglass prefab pools

Foundation wall materials

Concrete, CMU, wood

3 methods in which heat is gained or lost in buildings

Conduction Convection Radiation

Pile load test

Confirms design loads on pilings

Hardpan

Consolidated mixture of gravel, clay and sand. Good foundation base for buildings

High water table's impact on construction

Construction excavation must be braced/kept dry with pumping Basements must be waterproofed; walls designed to resist hydrostatic pressure Underground tanks must be designed to resist uplift Bearing capacity of soil is typically reduced

Site characterization contains what information

Contains geotechnical analysis of subsurface conditions: Depth to bedrock Depth to groundwater High water table Specific soil tests

Benefits of native plantings

Contributes to biodiversity Reduces/eliminates need for pesticides and fertilizers Reduced maintenance costs (requires less care) Increase/improve habitat

Incineration (brownfield)

Controlled burning of soil or solids to convert, degrade or oxidize contaminants. May be done on or off site

Exposure to radon

Cracks in solid floors Construction joints Cracks in walls Gaps in suspended floors Gaps around service pipes Cavities inside walls water supply.

Benefit of deconstruction

Creates more jobs and business opportunities than demolition

Symptoms of foundation failure/differential settlement

Distorted building frame Sloping floors Walls/glass crack Doors and windows inoperable

Causes of asbestos exposure

Disturbance of asbestos containing material Released into the air.

Deflectors (streams)

Divert flow Deepen a channel

Methods to increase bearing capacity and/or decrease settlement of soil

Drainage/dewatering Fill compaction Densification Surcharging Mixing Geotextiles Deepening or increasing the bearing area of footings Remove soft/organic soil and replace with granular materials (expensive) Cover compressible soil with porous layer of sand, gravel, crushed rock.

Detention basin

Dry basin that only fills with water when it rains Releases water at a pre-development flow rate via an outlet

Stormwater infiltration and recharge methods

Dry wells Filter Strips Sand filters Infiltration trench Infiltration basin Rain gardens

Standard pipe materials

Ductile iron or steel ABS Cast Iron Concrete HDPE PVC Vitrified Clay pipe

Characteristics of cast iron pipe

Durable Low thermal expansion No more durable than PVC High energy and environmental impacts

Earth movement and clay subsoils

Earth movement more likely to occur due to expansion and contracting of soil.

Where are PCBs found?

Electrical heat transfer and hydraulic equipment Plasticizers in paint Fluorescent light ballasts Cable insulation Oil based paint Caulking Plastic Floor finish

Swales

Encourage infiltration Reduces the velocity of water Less expensive than pipes Easy to maintain More natural approach than curb Use geotextiles in areas with greater velocities

Conduction

Energy is transferred by direct contact (touching a hot stove)

Convection

Energy is transferred through a medium-- liquid or gass-- caused by molecular motion (boiling water)

MX durability grade

Exterior grade

Foundation depth (frost 12"+)

Foundation/basement beneath frost depth

Relationship between foundations and expansive soils

Foundations must be isolated from them. Utilize deep foundations (piles or caissons) that bear on material below the expansive soil Utilize concrete grade beams

Two methods of relieving hydrostatic pressure around a building structure

Gravel drain (difficult to do) Drainage mat

Sanitary sewer (characteristics)

Gravity flow most common Flow calculated by using peak flow Pipe diameter < 8" Regularly spaced manholes

3 Types of retaining walls

Gravity wall Cantilever wall Counterfort wall

Environmental risks (high)

Habitat alteration Species extinction Overall loss of biodiversity Stratospheric ozone depletion Global climate change

Water-resistant

Having no openings larger than capillary pores that permit leakage of water

Characteristics of concrete pipe

Heavy and expensive to install Durable Useful when significant loads are required

Environmental risks (medium)

Herbicides/pesticides Oil spills Toxins, nutrients Biochemical oxygen demand Turbidity in surf Acid deposition Airborne toxins

Relationship between temperature and water vapor

High temperatures can hold more water vapor

Direction in which water vapor moves

High to low pressure (inside to outside, climate depending)

Needle beams

Horizontal beams inserted through a foundation or pier, which transfers the loads to adjacent soil.

Key global climate changes

Increase in carbon dioxide World's oceans are becoming warmer Rising ocean levels (thermal expansion and glacier runoff) results in erosion and floods Oceans more acidic due to more carbon dioxide Increase precipitation and droughts Increase in plants (due to more carbon dioxide)

Relationship between global warming and cooling costs

Increase in global warming results in an increase in cooling costs

Negative side waterproofing installation

Installed on side not exposed to water

CERCLA

Landowner is liable for environmental conditions whether they know about it or not-- cost of cleanup, damage to 3rd parties

Type III Abrasion resistance grade

Least resistant Residential or light duty patios

Treatment of asbestos

Leave undamaged asbestos alone Repair: seal/encapsulate Remove

Characteristics of ABS pipe

Lighter than PVC More expensive than PVC Twice thermal expansion of PVC MFR involves a number of toxic materials

Alluvial soils

Loose, saturated soils transported and deposited through action of flowing water Unsuitable for foundations

Bioremediation (brownfield)

Microorganisms used to degrade organic compounds in soils or groundwater. May be done in situ or ex situ.

Plastic limit of soil

Moisture content at which soil loses its plasticity and begins to behave like a solid.

Moisture problems in soil derive from

Moisture leaks into a building via capillary action or hydrostsatic pressure Precipitation Water vapor in the air

Plastic soil

Moldable when wet

Membrane waterproofing

Most common Several layers of asphalt saturated felt Applied on earth-contacting side of walls Water pressure will force the membrane against waterproofed surface. Protected from puncture by a coat of cement plaster, fiberboard or wythe of masonry

Core borings

Most costly Reliable Made with a diamond drill that is hard enough to cut through rock.

Environmental risks (low)

Oil spills Groundwater pollution Radionuclides acid runoff to surface water Thermal pollution

NX durability grade

Only used for interiors, no wet or freezing environments

Retaining wall failture

Overturning sliding Undermining

Sources of lead

Paint Ceramics Pipes/plumbing Soil Drinking water Windows and window sills Doors and door frames

Sand

Particles from .05 mm to 2 mm in diameter Finest grains just visible to the eye Excellent for construction loads, drainage and sewage drain fields Unsuitable for landscaping

Silt

Particles from .05mm to 2mm in diameter Grains are invisible but can be felt as smooth Stable when dry or damp but unstable when wet Swells and heaves when frozen Compresses under load Building foundations and road bases must extend below it or must be elastic enough to avoid damage

Critical element in designing plazas and patios

Pavers

Levels of watertightness

Permeable Pervious Water-resistant Water-repellent Waterproof

Pervious (watertightness)

Permitting leakage or flow of water through cracks, leaks or other openings

Surface drainage system options

Pervious paving Sheet flow Gutters built into roadways and parking areas Ground swales

Phytodegredation

Phytotransformation. Breakdown of contaminants taken up by plants through the metabolic processes within the plant or the breakdown of contaminants surrounding the plant through the effect of enzymes produced by the plants

Grade beam characteristics

Piles are driven or drilled and connected with a continuous beam Used with expansive soils or clays are encountered near the surface

Surcharge foundation

Placement of mass of fill over the building limits to preload underlying soil and induce settlement prior to construction. Typical amount of surcharge is 1.5 to 2.0 times the weight of building to be constructed

Common causes of erosion and sediment and control fails

Poor site analysis Incompatible site and design Inadequately designed facilities Wrong materials Poor install Poor maintenance Seasonal differences

Exposure to PCBs

Poorly maintained hazardous waste sites Illegal dumping Leaks from electrical transformers Burning waste Accumulates in leaves and above-ground parts of plants, food crops and fish.

3 Positions waterproofing can be applied in

Positive Negative Blind

Environmental strategies for using concrete

Precast forms Recycle asphalt paving

Head

Pressure caused by weight of water

Vapor barriers

Prevent passage of water vapor

Waterproofing

Prevents penetration of water under hydrostatic pressure

Underpinning

Process of rebuilding or strengthening the foundation of an existing building or extending it when a new excavation in adjoining property is deeper than the existing foundation.

What should architect confirm in geotechnical report

Project/location Reference elevation of boring Water table elevation Understand relation between blow counts, boring depth, footings and soil. Soil beneath footing affects foundation performance.

How soil class definition is determined

Properties of top 100' of soil needs to be determined

Two steps in site analysis

Proposal phase to facilitate winning the work Post contract phase

Small Business Revitalization Act

Protects against CERCLA.

Landslide mitigation options

Provide setbacks Drainage (minimize water) Redundant (utility infrastructure)

Excavation bracing

Provides support against soil and water pressure as excavation deepens.

Design strategies directed towards minimizing the amount of impervious surface and maintain predeveloped rate of infiltration (parking)

Reduce parking space size Require smaller spaces dedicated to compact cars Design spillover parking with pervious paving

Moisture, soil and building problems

Reduction in a soil's loss bearing capacity Leakage of water into building Disintegration of certain building materials

Landscape restoration options

Rehabilitation Reclamation Remediation

Preferred method of storm water quality management

Reintroduce runoff into soil quickly to allow for recharge

Relationship between relative humidity and temperature

Relative humidity declines as temperatures increase

PCB removal

Remediation of waste, soil, gravel, concrete, buildings

Treatment of unsuitable soil on site

Remove and replace with compacted fill

Filter strips (characteristics)

Remove particulates (metals, phospherous, etc) by filtration through surface of the vegetation Promotes infiltration, slows runoff Minimum slope: 2% Usually grass Minimum 15' wwide Perpendicular to sheet runoff

Soil vapor extraction (brownfield)

Removes VOCs from soil through the use vapor extraction wells. Sometimes used in conjunction with air injection systems. Contaminants are volatilized and flushed in the air for treatment

Benefits of storm water infiltration

Removes particulates and pollutants that attach to soil particles Significant reduction in loss of recharge water

Sand filters (characteristics)

Removes suspended solids No biological treatment capability Minimum 1.5' deep Should be used in conjunction with other media or systems Used in conjunction with peat

Solidification (brownfield)

Removes water and changes the soil or solid media chemically to reduce permeability and transport of contaminants by percolation

Elevation change supports

Retaining walls Earth reinforcing Gabions

Methods of increasing slope resistance

Retaining walls Thermal treatment

Retention basin (characteristics)

Retains water in a pool Only outlet is emergency spillway Depth is usually 6" - 24" deep

Channelized flow erosion

Rill and gully erosion

Relationship between plant/tree-life and stream quality

Roots of trees, sedges and shrubs-- bind soils of banks to increase stability of stream banks and resist erosion Overhanging vegetation shades stream (cooler H20) Biotic debris decays and provides nutrients Biota contributes to the health of riparian and upland soils

Strategies to reduce storm water runoff in arid areas

Sand filters Filter strips Bioretention Minimize ground water pollution

Good aquifer materials

Sand, gravel, sandstone

Deconstruction

Saves useful materials for reuse in new construction and rehab projects

Requirements for foundations

Secure against structural failure Minimal settlement Technically and economically feasible

Bioretention basin

Shallow areas designed to collect storm water Drain fairly quickly Allows typical landscape plants to be used

4 basic types of applied waterproofing

Sheet membrane Fluid applied Cementitious Bentonite systems

Maximum desirable slope of walks adjacent to buildings

Should not exceed 4%

Dessication

Shrinking of soil due to capillary action. Leaves to overconsolidation.

Counterfort Retaining Walls

Similar to cantilevered wall but with counterforts placed at distances equal to or larger than one half height. Counterforts are used for walls greater than 25'

Solvent extraction (brownfield)

Similar to soil washing but solvents are used to remove contaminant from soils or solid media

Test pit (characteristics)

Simple excavation that permit direct visual inspection of the actual soil conditions. Allows close-up examination of the soil layers. Not dug below water table Costly

Gravity retaining wall

Simple, lots of material and variety of types. Low walls to 8-10'

Site analysis checklist

Site condition Zoning regulations Landscape ordinance Land development regulations Utilities access Traffic Topography Soils/geology Hydrology Vegetation/wildlife Historic or cultural features Existing parks/public areas Environmental concerns

Relationship between site work and storm water runoff

Site work results in an increase of storm water runoff

How number of tests to determine bearing capacity of soil is determined

Size and nature of building Size of site Type of soil Minimum of 3 or 4 observations (typically at corners)

Drainage in parking areas

Slopes should be between 1.5 and 5% Water should drain toward the edges of the parking area

Dry wells (characteristics)

Small excavated pits backfilled with aggregrate Collect runoff from small areas such as a roof Visible/near structure. appearance is important Soil filter can be used to make it disappear Can be incorporated into catch basic

Silty soil

Smaller particles with occasional plastic behavior

How to recognize expansive soils, wet

Soil is stick and will accumulate on shoes (2-4") Molded into a ball by hand and will leave a powdery residue on hands when dry Knife or shovel will penetrate easily Cut surface = smooth and shiny Heavy construction equipment will develop a thick coating

Determinants of feasibility of infiltration

Soil texture (adequate percolation) Ponding or dewatering must be a minimum of 3 days but no more than 7 days Minimum of 2' - 4' is available between water table/bedrock Nature of site (slope) and nature of soil will permit locations of foundations, utilities, etc

Underconsolidated soil

Soil that is built up in river delta, or similar, and are deposited in a very loose state. Souls tend to consolidate over time.

Soil strength

Soil's ability to resist deformation. Function of friction and cohesion of grain - grain contact in soil

Colluvial soils

Soils transported by gravity (landslides)

Most common types of shoring supports

Soldier beams and lagging Sheet piling

Gabions

Steel mesh cages filled with small rocks, absorb wave energy.

3 Stream zones

Stream zone Middle zone Out of transition zone

Phytoextraction

Subprocess of phytoremediation in which plants remove dangerous elements or compounds from soil or water (usually heavy metals)

Underground drainage conduits

Sufficiently sloped to be self-cleaning Minimum of .3% Placed at an adequate depth below the ground surface to avoid damage by vehicles and to prevent freezing

Sheet erosion

Surface and runoff flows in a sheet

Two types of site stabilization

Temporary Permanent

Types of soil exploration tests

Test pits Soil load tests Borings

Variables in effective planting design synthesis

Textures Color Line Form Balance

Hydrostatic pressure

The pressure of water against the walls of its container.

Green roof installation on metal deck

Thermal barrier Rigid insulation Waterproof membrane Root barrier Drainage layer Growth medium

How planted parking lot islands impact stormwater runoff

They can intercept stormwater Shade and cool parking lots (reduced maintenance costs)

Deep excavation for a high rise building in an urban area requires

Tiebacks

Sheet piling

Timber, steel or precast concrete planks driven vertically side by side to retain earth and prevent water from seeping into an excavation

When is underpinning utilized

To deepen foundation based on new work To provide additional foundation capacity to an inadequately supported structure to provide new loads to existing structures

Void ratio (soil)

To determine compressiblity/compaction Loose soils high void ratio

Grain shape (soil)

To estimate shear strength

Liquid and plastic limits (soil)

To obtain compressibility and compaction values

Bored (drilled) pile

Transmits load to soil by skin friction. Vertical shaft drilled into the ground and filled with concrete.

Constructed wetlands

Treatment system for on-site sewage disposal systems that have physical limitations Requires a septic stank Limited capacity to treat solids

Location of trees : building

Trees should be planted 1/4 to 1/3 of their mature height away from the building

Ditches (dewatering)

Trench dug beneath water table. Water is directed to low point and pumped out. Typically at perimeter of job site.

Aquifer

Underground permeable material through which water flows

Phytoremediation (brownfield)

Use of selected plans to remove or biostabilize contaminants in soil, sediments or water

Stormwater management

Use of structural or nonstructural practices designed to reduced stormwater runoff pollutant loads, discharge volumes and peak flow discharge rates

Gravity Retaining Walls (characteristics)

Used for low retaining walls Resist forces on it by its own weight and by soil pressure and soil friction against its surface opposite to earth forces

Retaining wall batter

Used on taller retaining walls, wall tilts in to give impression that wall will not topple over

Type S Mortar

Used when freezing is expected

Type M mortar

Used when freezing is not expected

When to use a wash boring (soil exploration)

Used when soil is too compact to use an auger Useful in locating bedrock Uses a 2" - 4" diameter pipe that is driven into the soil and contains a smaller jet pipe through which water is forced.

Dry sample borings

Utilize a drive pipe with a special split sampling pipe at the tip.

Soil Mixing

Utilized to remediate soil contaminated with a chemical by blending it with a chemical that renders it harmless

Phase I Environmental Assessment

Utilized when site was previously used for industrial or commercial activities or if owner requires a higher standards of care. Cost effective No collective or testing of samples Cannot definitively determine contamination, only that there might be

Floating/compensated foundation

Utilized when soft soils are susceptible to settlement and dense soils are too far down to reach with deep foundations similar to mat foundation but is placed beneath building.

Tiebacks (excavation bracing)

Utilized when subsoil conditiosn permit.

N-year storm

Value of n is based on the probability that a storm of this magnitude or greater will occur at this location in any given year.

Stream buffer

Vegetated area near a stream, usually forested that helps shade and partially protect stream from impact of adjacent land uses. Plays key role in water quality.

Green roofs (characteristics)

Vegetated roof covers Reduce runoff in a temperate climate by 50% Absorb carbon dioxide Reduce ambient air temps Filters the air Reduces heat island effect Protect roof membranes from UV light degradation, temp extremes, wind/hail Adds acoustical insulation Adds aesthetic appearl to roof

Temporary methods of site stabilization

Vegetation Geotextiles Stone

How to lower radon levels

Venting from beneath house. Seal foundation and cracks.

Dynamic head

Vertical distance pump must life the water

Environmental issues with PVC

Vinyl chloride is a carcinogen (results in presence of dioxin) Burning of PVC = dioxin in environment

Soil washing (brownfield)

Water is used to flush through soils or medium to flush contaminants out. May involve removing solids and using mechanical agitation Additives may be used to increase the efficiency of the process

Drawback of storm water infiltration

Water soluable pollutants such as nutrients, pesticides or salts dissolve in water

Sheet flow drainage

Water that drains across a sloping surface whether the surface is paved, grassy or otherwise landscaped

Green roof installation on concrete deck

Waterproof membrane Root barrier Drainage layer Filter fabric Growth medium

Rainwater cistern properties

Watertight: prevent contamination Opaque: prevent algae growth

Dewatering Methods

Well points, deep wells, ditching/sump pumps

Areas not suitable for site development

Wetlands Above a 100'-year flood plain Habitats for endangered species Historic sites Prime farmland

Dew point

When relative humidity is 100%

Sanitary sewer trench depth (key factors)

Worker safety Cost of installation and maintenance Loading on pipes Wider trenches = less support

Underground water zones

Zone of aeration Ground water table Zone of saturation

Ground slope surfaces

a. minimum slope for surface drainage b. proper slope away from building edge c. proper slope for range of drainage ditches d. maximum slope for a grassed area e. maximum slope for stable soil and surface is protected (ivy, rocks, etc)

Rakers (excavation bracing)

angled supports that transmit forces into the ground

Treated lumber finishes

creosote (oil) pentachlorophenol (oil) copper napthenaic (oil) chromated copper (water) ammoniacal copper quaternay compound

ASTM 4 step process for conducting life cycle assessment

define goals analysis of inventory impact assessment interpretation of findings

Rainwater availability calculation

(Catchment area)(Average rainfall)(factor)

Dioxin

one of the most toxic human-made chemicals. Stable, long-lived, by-product of herbicide production enters environment as fallout from the incineration of municipal and medical waste and persists for many years.

Most sustainable type of development

redevelopment

Dewatering

removal of water from an excavation before and during excavation

PCBs

synthetic chemicals containing chlorine that are used in the manufacture of plastics and other industrial products, become stored in the tissue of animals, and also persist in the environment

Frost action

the alternate freezing and thawing of soil and rock

Dewatering excavation site methods

well points slurry walls soil mixed walls (watertight barriers) soil freezing

Surface water is directed to

yard drains catch basins underground storm drain lines

Minimum slope required for drainage at building

2%

Drainage ditch slope

2% - 10%

Distance between bottom of infiltration facility and water table/bedrock

2' - 4'

Typical height of cantilevered retaining wall

20 - 25'

Spacing of soil test pits/test borings

25 - 150' for multistory buildings 50 - 200' for single story buildings

Maximum desirable slope of grassy recreation areas

3%

Typical spread footing dimensions

3' x 3' minimum 20' x 20' maximum

Percentage of US electricity is generated by burning coal

50%

Reasonable time frame to drain an infiltration structure

72 hours

Problematic radon level

< 4 pci

Rough grading

Addition or removal of earth prior to the start of construction

Earth reinforcing

Alternative to conventional retaining wall, where soil is compacted in layers,each sandwiched between meshes of steel

Drivers in design of drainage system

Amount of runoff Intensity and duration of storms Size of area drained Characteristics of drained area (soil porosity, slope and vegetation cover) The amount of streets, paving, parking areas, roofs

Passive treatment wells (brownfield)

Barriers are construction of reactive materials and installed in an aquifer to promote a chemical reaction between the barrier and the contaminant in the groundwater. ie limestone barrier used to increase the pH of groundwater

Bed material components

Base layer, setting layer (leveling course)

Geotechnical information needed for soil to balance site

Bearing capacity Bulking factor Depth and character of bedrock

Plate load test

Bearing capacity of soil static loads on spread footings

Health issues caused by PCBs

Cancer Compromised immune system Reproductive issues Endocrinological issues

Dechlorination (brownfield)

Chemical treatment to remove chlorine atoms bonded to hazardous chemicals. Hydrogen or hydroxide ions are used to detoxify materials

Reclamation (landscape restoration)

Construct new landscape

Types of underpinning

Continuous Intermittent

Types of excavation bracing

Crosslot bracing Rakers Tie backs

Building foundation must support these loads

Dead load Live load Rain and snow loads Wind loads Seismic loads Soil and hydrostatic pressure Buoyant uplift load Flood loads

Plasticity index (soil)

Difference between liquid limit and plastic limit.

Brownfield Redevelopment cleanup standards

Do nothing Use administrative/institutional controls Engineering controls On-site remedial action Off site disposal/treatment (most expensive)

Deep foundation types

Driven piles Bored piles Caissons

Benefits of balloon framing in cold climates

Eliminates thermal bridge.

Principal reason for soil testing

Establish intrinsic characteristics of soil

Floating foundation installation

Excavate soil equal to weight of building Install mat or raft foundation. One foot of soil removed is equal to one story of the building to be constructed.

Peat (and other organic materials)

Excellent for landscaping Unsuitable for building foundation and road bases

Plasticity index of less than 15

Expansive soil

Retaining wall and depth in soil

Extend 2' below or 1/2 the above grade height to frost line (whichever is greater)

Consequences of expansive soils

Extensive cracking of sidewalks, foundation failures, retaining wall failures

SX durability grade

Exterior grade; utilized where freezing will occur

Source of dioxins

Fatty tissue of animals Food

Permanent methods of site stabilization

Finished surface Vegetation Paving Geotextiles Stone

Storm water

Flow of water on ground surfaces or drainage channels produced by rainfall or melting snow

Relationship between foundations and frost line

Footings and foundations must be placed below the frost line to prevent the structure from lifting up

Location of footing

Footings should rest on undisturbed native soil and extend beneath frost depth.

Building's foundation in relation to water table

Foundation should be located well above the site's water table

Nonvegetative stream bank stabilization

Gabions Deflectors

Soil grain classification

Gravel Sand Silt Clay

Higher soil bulk density

Greater support it can provide for foundation

Retaining walls

Hold soil back to allow for an abrupt change in elevation.

How are pool pumps specified

Horsepower and head

Landscaping improvements on energy efficiency

Improve energy efficiency by 30% Provides shade for buildings Evaporative cooling, transpiration and latent heat of evaporation May reduce reflected light from buildings Sunscreens

Water-repellent

Incapable of transmitting water by capillary action but able to transmit water under pressure

Problems caused by improper runoff control

Increased load on local sewers Increased potential flooding Pollution of waterways with sediment road salt, etc Erosion of sites and waterways Erosion of stream banks Accelerated soil creep or landslides Stream warming Loss of acoustic biodiversity

Air sparging (brownfield)

Injection of air into groundwater to flush volatile contaminants which are collected and treated by the soil vapor extraction processes

Blind side waterproofing installation

Installed before the element is built

Positive side waterproofing installation

Installed on side exposed to water Most common

Capped site development

Isolates and contains contaminated material from receptors and from and from natural transport mechanisms. Trenches can be lined with cap material

Treating soil in permanently cold environments

Keep soil frozen in order to maintain strength. Self contained convection Mechanical refrigeration.

Methods of sewage treatment

Large scale treatment plant Constructed wetlands

Vitrified Clay Pipe Characteristics

Largely replaced by PVC Durable Resistant to chemical corrosion Lowest thermal expansion Heavy = more handling; greater labor costs for install

Water pollution non point sources

Less easily to identify source

Portion of home at risk for radon exposure

Levels beneath the 3rd floor.

Cohesionless soil

Little to no friction when loose. Must be confined to support loads Granular soils Gravels Sands Silt Little to no clay content

When to use bored pile over driven pile

Loads are exceptionally high and bearing surface reliable Work is in close proximity to existing structures where vibration from driven piles may damage existing structures Inspecting bearing surface is important and limited inspection of the bearing material is possible.

Benefits of meadows (versus lawns)

Low maintenance Mowed only once a year, in the fall

Treatment of formaldehyde

Lower humidity level Increase ventilation

Characteristics of HDPE pipe

Lowest cost Lightest and most flexible of pipe materials Easy to manufacture Easily recyclable Greatest expansion coefficient (< PVC)

Health issues caused by asbestos

Lung disease Mesothelioma Asbestosis

Pervious paving

Material that can withstand vehicular or pedestrian traffic, but allows water to pass through and seep into the ground below.

Unmowed ground cover slope parameters (drainage)

May be as steep as 50%

Soil shear strength

Measure of frictional resistance and cohesion of a soil.

Type II Abrasion resistance grade

Medium resistance Restaurant entrances

Types of waterproofing

Membrane waterproofing Waterstops

Remediation (landscape restoration)

Mitigating a condition that caused destruction

Tilt

Mixture of clay, silt, sand, gravel and boulders deposited by glaciers

Slurry wall

More expensive form of excavation support that is economical if it becomes part of the permanent foundation of the building. Constructed by excavating a trench in short lengths, filling it with a slurry of bentonite and water to prevent the sides from collapsing

Shallow foundations

Most economical Employed when stable soil of adequate bearing capacity occurs relatively near to the ground surface.

When to use auger borings (soil exploration)

Most effective in sand, clay or depths not exceeding 50' Auger stops at the first obstruction

Type I Abrasion resistance grade

Most resistance Driveways

Durability grades for pavers

NX MX SX

Water content (in cohesive soils)

Obtain compressiblity and compaction values

Mat footing characteristics

One large footing beneath the entire building Raft foundation

What should occur before a land title is transferred

Phase 1 environmental assessment and a transaction screen

Liquid limit of soil

Point at which soil liquifies (plastic to liquid state)

Splash erosion

Raindrops on unprotected soil

Sources for potable water

Recycling water (limited) Desalinization (energy insensitive) Expanding use of existing sources Conservation (affordable)

Methods of reducing storm water runoff

Reduce impervious paving Reduce roofs Infiltration Detention and retention ponds Green roofs

Cantilevered retaining wall

Resists forces by the weight of the structure as well as by the weight of the soil on the heel of the base slab.

Rehabilitation (landscape restoration)

Restore environmental function

Negative characteristics of lawns in sustainable design

Results in use of pesticides, fertilizers, mowing

Dewatering alternates

Sheet piles/slurry walls Freezing gorund

Two main sources of radon

Soil water

How to recognize expansive soils, dry

Soil is hard, resists penetration by knife Cut from shovel leaves a shiny surface Surface may display cracks in a regular patten Width and spacing of cracks indicate the relative expansion potential of the soil when wetted Surface irregularities (footprints, tire tracks) cannot be obliterated by foot pressure

Bedrock

Solid material that forms the crust of the earth Generally the strongest support for the foundation of a structure

Brownfield cleanup options

Solidification Soil vapor extraction Incineration Bioremediation Soil washing Solvent extraction Dechlorination Phytoremediation Air sparging Passive treatment wells

Water pollution point sources

Source and owner can be identified

Key soil properties to test for

Specific gravity Grain side Grain shape Liquid and plastic limits Water content Void ratio Unconfined compression

Shallow foundation types

Spread footings Basement Crawlspace

Column Footing

Spread the load from the structure and the foundation over a large area so the load capacity of the soil is not exceeded and settlement is minimized Act like inverted beams (compression and tension)

Types of pond pumps

Submersible and larger centrifugal pumps

Geotechnical report

Summarizes info gained in soil exploration field tests Recommends foundation types and depths, bearing stresses

Crosslot (excavation bracing)

Temporary steel wide flange columns that are driven into the earth.

Cohesive soils

Tend to stick together, exhibit cohesion when submerged. ATTRACT WATER EXPANSIVE Fine grained soils Any soil with a significant amount of clay

Bored pile materials

Timber, steel, concrete, composite

Consolidated tilt

Well graded, strong and excellent for foundations

Issue with wash borings

Boulders may be mistaken for bedrock

Ideal driven pile installation

Cohesionless soils with few boulders When groundwater or methane gas is present above the suitable bearing soil layer

Ideal bored pile installation

Cohesive soils Obstructions that can be tolerated right away Dense reliable bearing surface

Wall footing

Continuous spread footing that serves the same purpose under a wall as a column footing

Dampproofing preventative measures

Draining surface water away from foundation Granular fill under a concrete slab (deters capillary action) Polyethlyene film vapor seal over granular fill Footing drains

Deep foundations

Employed when the soil underlying a foundation is unstable or of inadequate bearing capacity. They extend down through unstable soil to transfer building loads to a more appropriate bearing stratum of rock or dense sands and gravels below the superstructure Scour from water table can occur at surface Structure transmits tension loads to foundation Large horizontal loads transmitted to foundation Reducing settlement or differential settlement is crucial

Relationship between porosity and permeability

Greater porosity = low permeability

Methods of surface water from structures

Gutters Flumes Berms Warping of paved surfaces

Ground surface slope categorization

Level Easy Steep

Blow counts

N value. Number of blows required to drive device last 12" of standard penetration test.

Loam

Organic materials: humus, sand, silt, clay Excellent for agriculture Will settle a great deail over time.

Steep grade ground surface

Over 10% Most difficult to use More expensive for building construction because of complicated foundations and utility connections

5 basic types of spread footings

Single column Wall footing Combined footing Cantilever footing Mat/raft footing

Slabs on grade and moisture prevention

Slabs placed over a gravel several inches thick to prevent water from being drawn into slab via capillary action.

Easy grade ground surface

Slope between 4 and 10% Suitable for most construction and activity

Level grade ground surface

Slopes under 4% Suitable for construction and outdoor activities

Grain size (soil)

To estimate permeability, frost action, compaction and shear strength

Unconfined compression (in cohesive soils)

To estimate shear strength

Piles

Type of deep foundation Utilized if upper soils have insufficient bearing capacity to support spread footings Enables the building load to be transmitted to deeper, firmer soils Can be drilled or driven.

Finish grading

final distribution of earth at the conclusion of construction

Combined footing

Used to support 2 or more columns

Foundation walls

Utilized when basements are not required Need to support a limited load on firm soil exists. Typically 8" thick.

Cantilever footing

Utilized when footings are located tight to properly line. Eccentrically loaded.Exterior column footing joined by a concrete beam to an interior footing

Drilled caisson

Vertical shaft drilled into the ground and filled with concrete Bottom of the shaft is enlarged or belled to for a larger bearing area

Best drainage soil

Well graded coarse-grained (uniform sizes); uniform size = larger void volume

When to use boring tests

When information is required beyond the depth of a standard test pit/beyond depth of water table.

Residuum

soil derived from in place decomposition of bedrock materials (more weathered near surface; more rock-like with greater depth)