| |
       |
|
|
|
| AASHTO: |
American Association of State Highway
and Transportation Officials. |
| Abrasion
: |
Removal of material
due to a frictional contact. |
| Abrasion
And Scratch Resistance: |
Ability of a material
to resist the infliction of damage in the form of scratches, grooves
and other minor imperfections. |
| ABS: |
Acrylonitrile-Butadiene-Styrene;
a form of thermoplastic. |
| AC: |
Asbestos Cement; a
composite material used in pipe construction. |
| Acceptance: |
By the owner of the
work as being fully complete in accordance with the contract documents. |
| Adapter
Ring: |
In microtunneling,
a fabricated ring, usually made from steel, that serves to mate the
microtunneling machine to the first pipe section. This ring is intended
to create a waterproof seal between the machine and the spigot of
the first joint. |
| Addenda: |
Written or graphic
instruments issued prior to the execution of the agreement, which
modify or interpret the contract documents, drawings and specifications,
by addition, deletions, clarifications or corrections. |
| Additive: |
A substance added in
a small amount, usually to a fluid, for a special purpose such as
to reduce friction, corrosion, etc. |
| Admixture: |
Ingredients added
during mixing; often in construction to aid workability of concrete,
mortar or grout. |
| Advance
: |
The motion of the machine
in a direction toward the face wall of the entrance pit. |
| Advance
rate: |
Speed of advance
of a pipe jack or other trenchless installation through the ground,
generally expressed as either millimetres per minute or metres per
day. |
| Aerial
sewer: |
An unburied sewer (generally
sanitary type), supported on pedestals or bents to provide a suitable
grade line. |
| Aerobic: |
Presence
of unreacted or free oxygen (02). |
| Aggressive
Index (AI): |
Corrosion index established
by the American Water Works Association (AWWA) Standard C-400; established
as a criterion for determining the corrosive tendency of the water
relative to asbestos-cement pipe; calculated from the pH, calcium
hardness (H), and total alkalinity (A) by the formula AI = pH + log
(A * H). |
| Aggressive: |
A property of water
which favors the corrosion of its conveying structure, |
| Agreement: |
The written agreement
between the owner and the contractor covering the work to be performed;
the contract documents are attached to and made a part of the agreements.
Also designated as the contract. |
| Alkalinity: |
The capacity of a
water to neutralize acids; a measure of the buffer capacity of a water.
The major portion of alkalinity in natural waters is caused by (1)
hydroxide, (2) carbonates, and (3) bicarbonates. |
| Alumina: |
An oxide of aluminum
present in clay. |
| AMP: |
Asset Management
Plan; a structured approach for utilities to achieve long term defined
service standards ¡V or ¡V an external bearing used to isolate
the final drive from the thrusting force of the machine. |
| Anaerobic: |
Able to live and grow
where there is no oxygen. |
| Angle
of Repose: |
The angle which the
sloping face of a bank of loose earth, gravel, or other material,
makes with the horizontal. |
| Annular
filler: |
Material for grouting
the annular space between the existing pipeline and the lining system.
|
| Annulus: |
Free space between
the existing pipe and any lining. |
| Anode: |
(opposite of cathode)
The electrode at which oxidation or corrosion occurs. |
| ANSI: |
American National
Standards Institute, Inc. |
| Apparent
Tensile Strength: |
A value of tensile
strength used for comparative purpose that is determined by tensile
testing pipe rings in accordance with ASTM D 2290. This differs from
true tensile strength of the material due to a bending moment induced
by the change in contour of the ring as it is tested. Apparent tensile
strength may be at yield, rupture or both. |
| Apparent
Tensile Yield: |
The apparent tensile
strength calculated for the yield condition. |
| Application
for Payments: |
The form furnished
by the engineer which is to be used by the contractor in requesting
progress payments, and an affidavit of the contractor that progress
payments theretofore received from the owner on account of the work
been applied by the contractor to discharge in full all of the contractor's
obligations stated in prior applications for payment. |
| Approval: |
Accept as satisfactory. |
| Aqueduct: |
Large pipe or conduit
to convey water from distant source. |
| Aqueous: |
Pertaining to water;
an aqueous solution is a water solution. |
| ArcInfo?
: |
GIS program for sewer
data collection and display. |
| Areaway: |
A paved surface,
serving as an entry area basement or subsurface portion of a building,
which is provided with some form of drainage that may be connected
to a sewer line. |
| Arterials: |
Designation of a main
road system with many connecting minor roads. |
| As-Built: |
After a sewer has
been constructed it is checked for conformance to plan specifications.
The actual measurements (As-Built) are written on the plan near the
original plan measurements. The As-Built measurements are often set-off
in a box to differentiate the two measurements. Measurements are of
the elevations for the manhole top cover, manhole invert(s) and ground
level, for percent grade, etc. |
| ASCE: |
American Society of
Civil Engineers. |
| Asset: |
A valuable resource. |
| ASTM: |
American Society of
Testing and Materials, technical organization formed for the development
of standards on characteristics and performance of materials, products,
systems and services, and the promotion of related knowledge. |
| Auger: |
A flighted drive
tube having hex couplings at each end, to transmit torque to the cutting
head and transfer spoil back to the machine. |
| Auger
boring: |
A technique for forming
a bore from a drive pit to a reception pit, by means of a rotating
cutting head. Spoil is removed back to the drive shaft by helically
wound auger flights rotating in a steel casing. The equipment may
have limited steering capability. See guided
auger boring. |
| Auger
boring machine: |
A machine used to
drill earth horizontally by means of a cutting head and auger or other
functionally similar device. The machine may be either cradle
or track type. |
| Auger
MTBM: |
A type of microtunnel
boring machine, which uses auger flights to remove the spoil through
a separate casing placed through the product pipeline. |
| Auger
TBM: |
Tunnel boring machine
in which the excavated soil is removed to the drive shaft by auger
flights passing through the product pipeline pushed in behind the
TBM. |
| Automated
Spoil: |
An automated spoil
transportation system that conveys |
| Available
Water: |
Water necessary for
the performance of work, which may be taken from the fire hydrant
nearest the worksite, given conditions of traffic and terrain which
are compatible with the use of the hydrant for performance of work. |
| AWWA: |
American Water Works
Association. |
|
|
|
| Back reamer: |
A cutting
head attached to the leading end of a drill
string to enlarge the pilot
bore during a pull-back
operation to enable the carrier or sleeve
or casing
to be installed in. |
| Backfall: |
Refers to a length
of pipe having an upward gradient opposite to the direction of flow. |
| Backfill
Density: |
Percent compaction
for pipe backfill (required or expected). |
| Backflow
device: |
Mechanism that prevents
wastewater from flowing back upstream. |
| Backstop: |
Reinforced area of
the entrance pit wall directly behind the track. |
| Band: |
A ring of steel welded
at or near the front of the lead section of casing to cut relief and
strengthen the casing. |
| Baroid: |
Proprietary equipment
to measure the density of annulus grout. |
| Barrel: |
The vertical section
in a manhole between the cone and the benchwall. |
| Base (course): |
A layer of specified
or selected material of planned thickness, constructed on the subgrade
(natural foundation) or subbase for the purpose of distributing load,
providing drainage or upon which a wearing surface or a drainage structure
is placed. |
| Base
: |
The slab structure
which supports a manhole. |
| Base Resin: |
Plastic Materials prior
to compounding with other additives or pigments |
| Base
track: |
See master
track. |
| Batter: |
The slope or inclination
from a vertical plane, as the face or back of a wall. |
| Bedding: |
A prepared layer
of material below a pipeline to ensure uniform support. |
| Benching
or bench: |
The floor of a manhole
into which the channel is set; the bench is raised so that it can
drain to the channel. |
| Benchwall: |
The horizontal bottom
of the manhole normally out of the flow path. |
| Bent sub: |
An offset section of
drill stem close behind the drill head that allows steering corrections
to be made by rotation of the drill
string to orientate the cutting
head. Frequently used in directional
drilling. |
| Bentonite:
|
A colloidal clay
sold under various trade names that forms a slick slurry or gel when
water is added. Also known as drillers mud. See drilling fluid. |
| Berm: |
The space between the
toe of a slope and excavation made for intercepting ditches or borrow
pits. |
| Bid: |
The offer or process
of the bidder submitted on the prescribed form setting forth the prices
for the work to be performed. |
| Bidder: |
Any person, firm, or
corporation submitting a bid for the work. |
| Biological
Corrosion: |
Corrosion that results
from a reaction between the Pipe material and organisms such as bacterial,
algae, and fungi. |
| Bits: |
Replaceable cutting
tools on the cutting head or drill
string. |
| Bitumen: |
A hard or semi-hard
asphaltic residue; often used in construction as a waterproof/barrier
layer. |
| Bituminous
(coating): |
Of or containing bitumen;
as asphalt or tar. |
| Blind
shield: |
Non-mechanical shield
which has a controlled and partly sealed face. |
| BOD: |
Biological Oxygen Demand;
a measure of the need for oxygen by organic processes. |
| Bonds: |
Bid, performance
and payment bonds and other instruments of security furnished by the
contractor and his surety in accordance with the contract documents
and in accordance with the law of the place of the project. |
| Boots:
|
Electrical grade boots
worn by all operators. |
| Bore: |
A generally horizontal
hole produced underground primarily for the purpose of installing
services. |
| Boring
: |
(1) The dislodging
or displacement of spoil by a rotating auger or drill string to produce
a hole called a bore. (2) An earth-drilling process used for installing
conduits or pipelines. (3) Obtaining soil samples for evaluation and
testing. |
| Boring
machine: |
A mechanism to drill
earth. |
| Boring
pit: |
An excavation in the
earth of specified length and width for placing the machine on line
and grade. |
| Box: |
See female
hex connector. |
| Branch
sewer: |
A sewer into which
at least two sanitary, combined or stormwater sewers connect. |
| Breakout: |
Controls the joint
make and/or break mechanism. |
| Bridge
Plank (deck or flooring): |
A corrugated steel
sub-floor on a bridge to support a wearing surface. |
| Brittleness
Temperature: |
Temperature at which
50% of the tested specimens will fail when subjected to an impact
blow. |
| Budgets: |
An amount of money
needed or allocated for a specific use. |
| Building
combined sewers: |
A small diameter
pipe that conveys both wastewater and drainstormwater from a single
property to a combined sewer. |
| Building
sanitary drain: |
A small diameter pipe
that conveys wastewater from a single property (e.g. domestic home)
to a sanitary sewer. |
| Building
Sewer: |
The conduit which
connects building wastewater sources, to the public or street sewer,
including lines serving homes, public buildings, commercial establishments,
and industry structures. In this specification, the building sewer
is referred to in two sections. (1) the section between the building
line and the property line, frequently specified and supervised by
plumbing or housing officials; and (2) the section between the property
line and the street sewer, including the connection thereto frequently
specified and supervised by sewer, public works, or engineering officials
(Referred to also as "house sewer," "building connection,)' "service
connection," or "lateral connection"). |
| Building
stormwater: |
A small diameter pipe
that conveys stormwater runoff drain from the roof and any paved areas
of a single property to a stormwater sewer. |
| Buoyancy: |
The power of supporting
a floating body, including the tendency to float an empty pipe (by
exterior hydraulic pressure). |
| Burst
Strength: |
The internal pressure
required to cause a pipe or fitting to fail within a specified time
period. |
| Bushing: |
See female
hex connector. |
| Butt Fusion: |
A method of joining
polyethylene pipe where two pipe ends and rapidly brought together
under pressure to form a homogeneous bond. |
| Bypass
Pumping: |
The transportation
of sewage which flows around a specific sewer pipe/line section or
sections via any conduit for the purpose of controlling sewage flows
in the specified section or sections without flowing or discharging
onto public or private property. |
| Bypass: |
An arrangement of pipes
and valves whereby the flow may be passed around a hydraulic structure
or appurtenance. Also, a temporary setup to route flow around a part
of a sewer system. |
|
|
|
| Caisson: |
A watertight box
or cylinder used in excavating for foundations or tunnel pits to hold
out water so concreting or other construction can be carried on. |
| Camber: |
Rise or crown of the
center of a bridge, or Bowline through a culvert, above a straight
line through its ends. |
| Can: |
A principal module
which is part of a shield
machine as in microtunneling
or tunnel boring
machines (TBMs). Two or more may be used, depending on the installation
dimensions required and the presence of an articulated joint to facilitate
steering. May also be referred to as a trailing tube. |
| Cantilever: |
The part of a structure
that extends beyond its support. |
| Capital: |
A sum of money used
to implement projects. |
| Carbon
black: |
A black pigment produced
by the incomplete burning of natural gas or oil, that possesses excellent
ultraviolet protective properties. |
| Carriage: |
The mechanical part
of a non-split boring machine that includes the engine or drive motor,
the drive train, thrust block and hydraulic cylinders. |
| Carrier
pipe: |
The tube which carries
the product being transported and which may go through casings at
highway and railroad crossings. It may be made of steel, concrete,
clay, plastic, ductile iron, or other materials. On occasion it may
be bored direct under the highways and railroads. |
| Cased
bore: |
A bore in which a
pipe, usually a steel sleeve, is inserted simultaneously with the
boring operation. Usually associated with auger
boring or pipe
jacking. |
| Casing
: |
A pipe used to line
bore holes through which a pipe(s) called carrier pipes or ducts are
installed. Usually not a Product
Pipe. |
| Casing
adapter: |
A circular mechanism
to provide axial and lateral support of a smaller diameter casing
than that of the casing
pusher. |
| Casing
pipe method: |
Method in which a casing,
generally steel, is pipe jacked into place, within which a product
pipe is inserted later. |
| Casing
pipe: |
A pipe installed
as external protection to a Product Pipe. |
| Casing
pusher: |
The front section of
a boring machine that distributes the thrusting force of the hydraulic
cylinders to the casing and forms the outside of the spoil ejector
system. |
| Cast
iron (CI): |
Sewer pipe material,
sometimes provided as ductile cast iron. |
| Catastrophic
rainfall: |
Rainfall event of return
frequency far in excess of any event collection system design performance
criteria typically, say, a 1 in 200 year storm. |
| Catch
basin: |
A small buried structure
to divert overland stormwater flow into sewer flows. |
| Catchment: |
A geographical area
draining to a sewer or receiving water. |
| Categorization: |
A structured process
of placing items into sets according to related characteristics for
prioritization. |
| Cathode: |
The electrode of an
electrolytic cell at which reduction is the principal reaction (Electrons
flow toward the cathode in the external circuit ). Typical cathodic
processes are cations taking up electron and being discharged, oxygen
being reduced, and the reduction of an element or group of elements
from a higher to a lower valence state. |
| Cathodic
: |
A process by which
the corrosion of a metal pipeline may be protected by the use of an
electrical current. |
| Cathodic
corrosion: |
An unusual condition
(especially with Al, Zn, Pb) in which corrosion is accelerated at
the cathode because the cathodic reaction creates an alkaline condition
which is corrosive to certain metals. |
| Cathodic
protection: |
Preventing corrosion
of a pipeline by using special cathodes (and anodes) to circumvent
corrosive damage by electric current. Also a function of zinc coatings
on iron and steel drainage products - galvanic action. |
| Caulking: |
General term which,
in trenchless technology, refers to methods by which joints may be
closed within a pipeline |
| Cavitation: |
Formulation and sudden
collapse of vapor bubbles in a liquid; usually resulting from local
low pressures - as on the trailing edge of a propeller; this develops
momentary high local pressure which can mechanically destroy a portion
of a surface on which the bubbles collapses. |
| CCTV: |
Closed circuit television
used to carry out internal inspection and survey of pipelines. |
| Cell
: |
Electrochemical system
consisting of an anode and a cathode immersed in an electrolyte. The
anode and cathode may be separate metals or dissimilar areas on the
same metal. The call includes the external circuit which permits the
flow of electrons from the anode toward the cathode. |
| Cell Classification: |
Method of identifying
plastic materials, such as polyethylene, as specified by ASTM D 3350,
where the Cell Classification is based on these six properties: (1)
Density of Base Resin (2) Melt Index (3) Flexural Modulus (4) Tensile
Strength at Yield (5) ESCR (6) Hydrostatic Design Basis and Color |
| Cellar
Drain: |
A pipe or series
of pipe which collect wastewater which leaks, seeps, or flow into
subgrade parts of structures and discharge them into a building sewers
or by other means dispose of such wastewaters into sanitary, combined
or storm sewers (Referred to also as "basement drain"). |
| Centerline: |
The vertical distance
between the center of the drive chuck and the ground plane. |
| CFM: |
Cubic Feet per Minute;
a measure of flow volume. One CFM equals 0.472 liters per second. |
| Change
Order: |
A written order to
the contractor authorizing an addition, deletion or revision in the
work, within the general scope of work of the agreement, authorizing
an adjustment in the agreement price or agreement time. |
| Channel: |
A prepared flow route
within the bench of a manhole that conveys the incoming flow to the
downstream pipe. |
| Chemical
grouting: |
Method for the treatment
of the ground around a shaft or pipeline, using non-cementitious compounds,
in order to facilitate or make possible the installation of an underground
structure. |
| Chemical
resistance: |
Ability to render
service in the transport of a specific chemical for a useful period
of time at a specific concentration and temperature. |
| Chemical
stabilization: |
Renovation method in
which a length of pipeline between two access points is sealed by
the introduction of one or more compounds in solution into the pipe
and surrounding ground and, where appropriate, producing a chemical
reaction. Such systems may perform a variety of functions such as
the sealing of cracks and cavities, the provision of a new wall surface
with improved hydraulic characteristics or ground stabilisation. |
| Chimney: |
The small vertical
section between a manhole frame and cone which is built from brick,
masonry or concrete adjusting rings. |
| Chippers: |
See bits. |
| CIP: |
Cast
Iron Pipe |
| CIPP: |
Cured
In Place Pipe; a rehabilitation technique whereby a flexible resin-impregnated
tube is installed into an existing pipe and then cured to a hard finish,
usually assuming the shape of the existing pipe. |
| Circumferential
Coefficient of Expansion and Contraction: |
The fractional change
in circumference of a material for a unit change in temperature. Expressed
as inches of expansion or contraction per inch of original circumference
per ?/font>F. |
| Circumferential: |
Around the inner surface
of a circular pipe cross section. |
| Cleaning: |
An action of a boring
machine to remove spoil that occurs when the auger is rotating while
axially stationary. |
| Closed
face: |
The ability of a tunnel
boring machine to close or seal the facial opening of the machine
to prevent or slow the entrance of soils into the machine. Also may
be the bulkheading of a hand dug tunnel to slow or stop the inflow
of material. |
| Closed-Circuit
Television Inspection (CCTV): |
Inspection method
utilizing a closed circuit television camera system with appropriate
transport and lighting mechanisms to view the interior surface of
sewer pipes and structures. |
| Close-fit: |
Description of a lining
system in which the new pipe makes close contact with the defective
pipe at normal or minimum diameter. An annulus may occur in sections
where the diameter of the defective pipe is in excess of this. |
| Clutch: |
A mechanical device
that engages or disengages rotary torque from a power source. |
| COD: |
Chemical Oxygen Demand;
a measure of the need for oxygen by chemical processes. |
| Coefficient
: |
A scientifically
based factor that is taken into account during calculations. |
| Coefficient
of Thermal Expansion and Contraction: |
The fractional change
in length of a material for a unit change in temperature. |
| Cofferdam: |
A barrier built in
the water so as to form an enclosure from which the water is pumped
to permit free access to the area within. |
| Cohesionless: |
A material that does
not readily bond with other particles. |
| Cohesive
Soil: |
A soil that when
unconfined has considerable strength when air-dried, and that has
significant cohesion when submerged. |
| Colcrete: |
Proprietary equipment
to measure the workability of annulus grout. |
| Cold
bend: |
To force the Pipe
into a curvature without damage, using no special tools, equipment
or elevated temperatures. |
| Colebrook
White Prandtl: |
A formula for calculating
the flow through pipes. |
| Collapse: |
Critical failure
of a pipeline when its structural fabric disintegrates. |
| Collaring: |
The initial entry of
casing or a cutting head into the earth. |
| Collection
system: |
A network of sewers
which serves one or more catchment areas. |
| Collector
sewer: |
A sewer located in
the public way collects the wastewaters discharged through building
sewers and conducts such flows into larger interceptor sewers and
pumping and treatment works. (Referred to also as "street sewer.") |
| Colloidal: |
Very small insoluble
non diffusible particles that remain in suspension. |
| Combined
sewer sytem: |
A single network of
sewers designed to convey stormwater as well as sanitary flows. |
| Compaction: |
The densification
of a soil by means of mechanical manipulation. |
| Composite
ring brick sewer |
A brick sewer which
consists of a greater number of layers of brick above the springing
line than below the springing line. |
| Compounding: |
The process where
additives and carbon black are homogeneously mixed with the base polyethylene
|
| Compressed
air method: |
General term which,
in trenchless technology, refers to the use of compressed air within
a tunnel or shaft in order to balance ground water and prevent ingress
into an open excavation. |
| Compression
gasket: |
A device which can
be made of several materials in a variety of cross sections and which
serves to secure a tight seal between two pipe sections (e.g., "O"
rings). |
| Compression
ring: |
A ring fitted between
the end bearing area of the bell and spigot to help distribute applied
loads more uniformly. The compression ring is attached to the trailing
end of each pipe and is compressed between the pipe sections during
jacking. The compression rings compensate for slight misalignment,
pipe ends that are not perfectly square, gradual steering corrections,
and other pipe irregularities. Compression rings are also referred
to as spacers. |
| Conductivity: |
A measure of the
ability of a solution to carry an electrical current. conductivity
varies both with the number and type of ions the solution carries. |
| Conduit: |
A broad term that can
include pipe, casing, tunnels, ducts or channels. The term is so broad
that it should not be used as a technical term in boring or tunneling. |
| Cone: |
The section between
the top of a manhole wall and chimney or the frame. The diameter of
the manhole is reduced over the cone section to receive the frame.
The cone section may be concentric or eccentric. |
| Consolidation: |
The gradual reduction
in the volume of a soil mass resulting from an increase in compaction. |
| Continuous
sliplining: |
See sliplining
or lining
with continuous pipe. |
| Contract
documents: |
The Agreement, Addenda,
Instructions to Bidders, Contractor's Bid, the Bonds, the Notice of
Award, the General Conditions, the Supplementary Conditions, Special
Conditions, Technical Conditions, the Specifications, Drawings, Drawing
Modifications, and Notice to Proceed, all make up the Contract Documents. |
| Contract
price: |
The total moneys
payable to the Contractor under the Contract Documents. |
| Contract
time: |
The number of calendar
days stated in the Agreement for the completion of the work. |
| Contracting
officer: |
The owner (guarantee)
- The Individual who is authorized to sign the contract documents
on behalf of the owner's governing body. |
| Contractor: |
The person, firm or
corporation with whom the owner has executed the agreement. |
| Control
Console: |
An electronic unit
inside a container located on the ground surface, that controls the
operation of the microtunneling
machine. The machine operator drives the tunnel from the control console.
Electronic information is transmitted to the control console from
the heading of the machine. This information includes head position,
steering angle, jacking force, progression rates, machine face torque,
slurry and feed line pressures, and laser position. Some control consoles
are equipped with a computer that tracks the data for a real-time
analysis of the tunnel drive. |
| Control
lever: |
A handle that activates
or deactivates a boring
machine function. |
| Conventional
trenching: |
Method in which access
is gained by excavation from ground level to the required level underground
for the installation, maintenance or inspection of a pipe, conduit
or cable. The excavation is then backfilled and the surface reinstated. |
| Conventional
tunnelling: |
Methods of tunnel construction
ranging from manual excavation to the use of self propelled tunnel
boring machines. Where a lining is required bolted segmental rings
are frequently used. |
| Corbel: |
For brick manholes
this term is sometimes used in place of cone, and indicates the gradual
reduction in diameter by indenting brick |
| Core area: |
That part of a sewer
network containing the critical sewers, and other sewers where hydraulic
problems are severe and merit detailed investigation. |
| Corrosion
: |
The destruction of
a material or its properties because of a reaction with its (environment)
surroundings. |
| Corrosion
fatigue: |
Fatigue type cracking
of metal caused by repeated or fluctuating stresses in a corrosive
environment characterized by shorter life than would be encountered
as a result of either the repeated or fluctuating stress alone or
the corrosive environment alone. |
| Corrosion
Index: |
Measurement of the
corrosivity of a water (e.g. Langelier Index, Ryznar Index, Aggressive
Index, etc.) |
| Corrosion
Rate: |
The speed (usually
an average) with which corrosion progresses (it may be linear for
a while); often expressed as though it were linear, in units of mdd
(milligrams per square decimeter per day) for weight change, or mpy
(milligrams per year) for thickness changes. |
| Corrosion
Resistance: |
Ability of a material
to withstand corrosion in a given corrosion system. |
| Corrugated
pipe: |
Pipe with ridges (corrugations)
going around it to make it stiffer and stronger. The corrugations
are usually in the form of a sine wave a+B181nd are usually made of
galvanized steel or aluminum. |
| Cover: |
1) The lid at the
top of the manhole which can be removed when access to the interior
of the manhole is required. |
| Cracks: |
Fracture lines visible
around the circumference and/or along the length of a sewer. |
| Cradle
machine: |
A boring machine
typically carried by another machine that uses winches to advance
the casing. |
| Cradle: |
A structure constructed
from concrete or masonry that provides structural support to a sewer.
It typically surrounds the bottom and sides of a sewer up to the springing
line. |
| Creep: |
The dimensional change,
with time, of a material under continuously applied stress after the
initial elastic deformation. |
| Crew: |
The number of persons
required for the performance of work at a site as determined by the
contractor in response to task difficulty and safety considerations
at the time or location of the work. |
| Critical
sewers: |
Sewers with the most
significant consequences in the event of structural failure. |
| Cross
members: |
The lateral supports
under the track of a boring
machine. |
| Crossing: |
Pipeline installation
in which the primary purpose is to provide one or more passages beneath
a surface obstruction. |
| Crown:
|
(1) Top of pipe segment,
or (2) The highest elevation within a pipe. |
| Crush
lining: |
See Pipe
Eating. |
| CSO: |
Combined Sewer Overflow;
a hydraulic relief point within combined sewer systems designed to
discharge excess flows during wet weather to receiving waters. |
| Cured-in-place
pipe (CIPP): |
A lining system in
which a thin flexible tube of polymer or glass fibre fabric is impregnated
with thermoset resin and expanded by means of fluid pressure into
position on the inner wall of a defective pipeline before curing the
resin to harden the material. The uncured material may be installed
by winch or inverted by water or air pressure, with or without the
aid of a turning belt. |
| Customer: |
Sewer structure owner,
specifically the one requesting the inspection work. |
| Cut
and Cover: |
See Open
Cut. |
| Cutterhead: |
Any rotating tool or
system of tools on a common support that excavates at the face of
a bore. Usually appliesto mechanical methods of excavation. |
| Cutting
bit (cutter head) |
The actual teeth
and supporting structure that is attached to the front of the lead
auger, drill stem or front face of the tunnel boring machine. It is
used to reduce the material that is being drilled or bored to sand
or loose dirt so that it can be conveyed out of the hole. Usually
applies to mechanical methods of excavation, but may also include
fluid jet cutting. |
|
|
|
| Data logger: |
(Also field data logger.)
Keyboard-type device used to electronically record inspection data. |
| Data
reviewers: |
Personnel from other
departments who will review the recorded inspection information for
use in future repair planing or during the auditing process. |
| Dead man: |
A fixed anchor point
used in advancing a saddle or cradle type boring machine. |
| Debris:
|
Accumulation of material
consisting of organic (human waste, food wastes, etc.), (sand, gravel,
wood, etc.), grease or roots. |
| Deck assembly: |
Drive train assembly
for a split design boring machine. |
| Deformed
and reshaped: |
See modified
sliplining. |
| Department
contact: |
Assigned person responsible
to represent the owning department for decision making and necessary
notifications. |
| Dereliction: |
The gradual decay
of a sewer network accelerated by the negligence of effective maintenance. |
| Dewater: |
Any method used to
lower the water table in the vicinity. |
| Diameter
of reamer (d2): |
Largest diameter
of reamer. |
| Diameter
of standard bit (d1): |
Maximum outside diameter
of standard bit. |
| Dimple: |
A term used in tight
fitting pipeline reconstruction, where the new plastic pipe forms
an external departure or a point of expansion slightly beyond the
underlying pipe wall where unsupported at side connections. The dimples
are used for location and reinstatement of lateral sewer service. |
| DIP: |
Ductile Iron Pipe |
| Directional
drilling: |
A steerable system
for the installation of pipes, conduits
and cables in a shallow arc using a surface launched drilling rig.
Traditionally the term applies to large scale crossings in which a
fluid-filled pilot bore is drilled using a fluid-driven motor at the
end of a bend-sub, and is then enlarged by a washover
pipe and back
reamer to the size required for the product
pipe. The required deviation during pilot boring is provided by
the positioning of a bent
sub. Tracking of the drill
string is achieved by the use of a downhole survey tool. |
| Discharge
point: |
The point where the
flows in a sewer are discharged to |
| Discount: |
A reduction in the
calculated price. |
| Discrete
sliplining: |
See sliplining
or lining
with discrete pipes. |
| Diurnal: |
To vary during the
day. |
| Diverting: |
Modifying the normal
wastewater flow to allow access to some specific sewer structure;
often includes bypass pumping. |
| Dog
plate: |
See thrust block. |
| Dogs: |
Moveable protrusions
in the thrust block that engage holes or blocks in the track. |
| Double
ring brick sewer: |
A brick sewer which
consists of two layers of bricks. |
| Drainage
fixture unit: |
A drainage fixture
unit, often referred to as a fixture unit or FU, is a unit of measure
of the waste water flow generated by an appliance, such as a sink
or toilet. For example, the typical full bath has a value of 9 FUs.
See Availability Fee for cost. |
| Drill
bit: |
A tool which cuts
the ground at the head of a Drill
String, usually by mechanical means but may include Fluid
Jet Cutting. |
| Drill
string: |
1) The total length
of drill rods/pipe, bit, swivel joint etc. in a drill bore-hole. 2)
System of rods used with cutting bit or compaction bit attached to
the drive chuck. |
| Drilling
fluid/mud: |
A mixture of water
and usually bentonite and/or polymer continuously pumped to the Cutting
Head to facilitate cutting, reduce required torque, facilitate the
removal of cuttings, stabilize the borehole, cool the head and lubricate
the installation of the Product Pipe. In suitable soil conditions
water alone may be used. |
| Dripper: |
Applied to infiltration
to quantify water dripping into a sewer in a non-continuous way through
a defect or faulty joint. |
| Drive
chuck: |
The female hex connector
located within the casing pusher. |
| Drive
shaft: |
See Jacking
Shaft. |
| Drive/entry
shaft/pit: |
Excavation from which
trenchless technology equipment is launched for the installation of
a pipeline, conduit or cable. It may incorporate a thrust wall to
spread reaction loads to the soil. |
| Drop connection
manhole: |
A manhole in which
the influent pipe enters from above the effluent invert depth. If
the drop occurs in the manhole itself, it is called an "internal"
drop manhole. If the drop occurs a few feet upstream of the manhole,
it is referred to as a "external" drop. |
| Drop
manhole: |
If the upstream pipe
is at a greater elevation than the manhole invert then two inlet connections
to the manhole are made. One is through the wall at the same grade
as the upstream pipe, the other is at the invert so to direct flows
through the channel. The invert connection is made by incorporating
a pipe drop in the upstream pipe. The pipe drop may be outside or
inside the manhole. |
| Dry bore: |
Any drilling or Rod
Pushing system not employing drilling fluid in the process. Usually
associated with guided Impact
Moling, but also some rotary methods. |
| Duct: |
(1) In many instances,
a term interchangeable with pipe. (2) In the boring industry, it is
usually used for small plastic or steel pipes that enclose wires or
cables for electrical or communication usage. (3) Conduit inside which
a utility service is installed. |
| DWF: |
Dry Weather Flow; is
the base flow in a sewer prior to rain induced flows. |
| DWI: |
Dry Weather Inflow;
is the result of flow entering the collection system from connected
sources which are not caused by rainfall. Typically, this could include
water from fire fighting, hydrant abuse, street washing, sump pumps
etc. |
|
|
|
| Earth
piercing: |
(1) Term commonly used
in North America as an alternative to impact
moling. (2) The use of a tool which comprises a percussive hammer
within a suitable casing, generally of torpedo shape. The hammer may
be pneumatic or hydraulic. The term is usually associated with non-steered
devices without rigid attachment to the launch pit, relying upon the
resistance (friction) of the ground for forward movement. During operation
the soil is displaced, not removed. An unsupported bore may be formed
in suitable ground, or a pipe drawn in, or pushed in, behind the tool.
Cables may also be drawn in. |
| Earth
pressure balance (EPB) machine: |
Type of microtunneling
or tunneling machine in which mechanical pressure is applied to the
material at the face and controlled to provide the correct counter-balance
to earth pressures in order to prevent heave or subsidence. The term
is usually not applied to those machines where the pressure originates
from the main Pipe
Jacking rig in the Drive
Shaft/Pit or to systems in which the primary counter-balance of
earth pressures is supplied by pressurized drilling fluid. |
| Earth
pressure balance shield: |
Mechanical tunnelling
shield which utilises a full face to support the ground in front of
the shield and usually employs an auger flight to extract the material
in a controlled manner. |
| Easement
Access: |
Areas within an easement
to which access is required for performance of work. |
| Easement: |
A liberty, privilege,
or advantage without profit which the owner of one parcel of land
may have in the hand of another. In this agreement, all land, other
than public streets, in which the owner has sewer system lines or
installations and right of access to such lines or installations. |
| Effluent: |
A generic term used
to indicate the relative strength of sewer flows; from stormwater
to wastewater to industrial effluent, for example. |
| Efflux: |
Flowing out of. |
| EHMWHD: |
Extra High Molecular
Weight High Density as originally noted in ASTM D1248, Grade P34 materials
were specifically EHMW high-density polyethylene materials. |
| Ejector
pump: |
See Sewage
ejector pump. |
| Elastic
modulus: |
A measure of the
stress buildup associated with a given strain. |
| Electrofusion: |
The joining together
of parts using electrical energy. |
| Elongation: |
The increase in length
of a material stressed in tension. |
| Embankment
(or fill): |
A bank of earth, rock
or other material constructed above the natural ground surface. |
| Embrittlement: |
Loss of ductility
of a material resulting from a chemical or physical change. |
| Emergency
controls: |
Those controls that
stop power to machine or components. |
| Emergency
repair: |
A repair that must
be made while the main is pressurized, or flowing. |
| Emergency
stop: |
A red manually operated
push button that, when activated, stops all functions of the machine. |
| Encrustation: |
Used to describe
deposits left by the partial evaporation of infiltrating groundwater
containing dissolved salts. Can be classified into light, medium or
heavy by percentage loss of cross-sectional area. |
| End Section: |
Flared attachment on
inlet and outlet of a culvert to prevent erosion of the roadbed improve
hydraulic efficiency, and improve appearance. |
| Endurance
Limit: |
The maximum stress
that a material can withstand for an infinitely large number of fatigue
cycles (See Fatigue
Strength). |
| Energy
Gradient: |
Slope of a line joining
the elevations of the energy head of a stream |
| Energy
Head: |
The elevation of
the hydraulic gradient at any section, plus the velocity head. |
| Engineer: |
The person, firm or
corporation named as such in the contract documents; the "Engineer
of Record". |
| Entrance
pit: |
1) An opening in
the earth of specified length and width for placing the machine on
line and grade. 2) See boring
pit. |
| Entry
ring: |
See Launch
Seal. |
| Entry/exit
angle: |
Angle to the ground
surface at which the drill string enters or exits in forming the pilot
bore in a directional
drilling / guided
boring system. |
| Environment: |
The surroundings or
conditions (physical, chemical, mechanical) in which a material exists. |
| Environmental
stress cracking: |
The susceptibility
to crack or craze under the influence of specific chemicals stress
and/or mechanical stress. |
| EPA: |
United States Environmental
Protection Agency |
| EPB: |
Earth
Pressure Balance. |
| Epoxy: |
Resin formed by the
reaction of bisphenol and Epichlorohydrin. |
| Equalizer: |
A culvert placed
where there is no channel but where it is desirable to have standing
water at equal elevations on both sides of a fill. |
| Erosion: |
Deterioration of a
surface by the abrasive action of moving fluids. This is accelerated
by the presence of solid particles or gas bubbles in suspension. When
deterioration is further increased by corrosion, the term "Corrosion-Erosion"
is often used. |
| ERW: |
Electrical Resistance
Welding |
| Estimated
Remaining Life (ERL): |
A value determined
by the inspectors based on experience, judgment, and guidelines within
the manual that predicts the amount of time that a sewer structure
will remain in a "fit-for-use" condition. |
| Estuaries: |
Descriptive of the
transition where rivers meet the sea, and currents meet tides. |
| Execution
department: |
A department that provides
the sewer inspection service. |
| Exfiltration: |
The leakage or discharge
of flows being carried by sewers out into the ground through leaks
in pipes, joints, manholes, or other sewer system structures; the
reverse of "infiltrations." |
| Exit pit: |
An opening located
at the exit of the cutting head or casing. |
| Exit
shaft: |
See Reception
Shaft. |
| Expander: |
A tool which enlarges
a bore during a pull-back
operation by compression of the surrounding ground rather than by
excavation. Sometimes used during a thrust boring process as well
as during directional
drilling / guided
boring pull-back. |
| Extension
track: |
An additional section
of track used in front of the master track. |
|
|
|
| Fabric: |
Used to describe the
physical material from which a pipe is made: vitrified clay; brick;
concrete, for example. |
| Face
stability: |
Stability of the
excavated face of a tunnel or pipe jack. |
| Face: |
Wall of the entrance
pit into which the bore is made. |
| Fairings: |
Molding features
at the ends at the ends of pipes, usually of varying dimensions to
the main pipe, to facilitate easy jointing. |
| Fatigue
Strength: |
The stress to which
a material can be subjected for a specified number of fatigue cycles. |
| Fatigue: |
The phenomenon leading
to fracture under repeated or fluctuating stresses having a maximum
value less than the tensile strength of the material. |
| Feet per
second: |
US customary unit for
velocity. One foot per second equals 304.8 millimeters per second;
or 0.3048 meters per second. (abbrev. ft/s). |
| Feet: |
US customary unit
for measuring length. One foot equals 304.8 mm; or 0.3048 meters.
(abbrev. ft). |
| Female
hex connector: |
A hexagonal shaped
socket. |
| Ferro-cement: |
A rehabilitation
technique that employs steel fabric mesh, usually in multiple layers
but with the maximum mesh diameter not exceeding 2 mm (1/8 inch),
which is fixed to the existing sewer and then covered in high strength
grout, either placed in situ by man
entry work to form a structural lining or pre-formed into segments
for later installation. |
| Field
data logger: |
See data
logger. |
| Field
Orders: |
A written order issued
by the engineer clarifies or interprets the contract documents in
accordance with the terms of the contract or orders minor changes
in the work in accordance with the terms of the contract. |
| Filter: |
Granular material placed
around a submarine pipe to facilitate drainage and at the same time
strain or prevent the admission of silt or sediment. |
| Final
drive: |
The final reduction
unit in the drive line. |
| Fit-for-use
criteria: |
Criteria used to determine
if sewer structures are in a condition that justifies continued operation
for its designated service. |
| Fixture
Unit: |
See Drainage
fixture unit |
| Flare
or flaring: |
The bending out of
the front end of the lead joint to give clearance. Depending on ground
conditions, the flares may have all cracks, or cuts fully welded,
or a complete flare not welded, or a segmented flare where only portions
of the joint are flared. |
| Flash
Point: |
Temperature at which
a material begins to vaporize. |
| Flexible: |
Readily bent or deformed
without permanent damage. |
| Flexural
Modulus: |
The slope of the
curve defined by flexural load versus resultant strain. A high flexural
modulus indicates a stiffer material. |
| Flexural
Strength: |
The strength of a material
in bending expressed as the tensile stress of the outermost fibers
at the instant of failure. |
| Flight: |
The spiral plates
surrounding the tube of an auger. |
| Flow :
|
(1) Turns drilling
fluid flow on. (2) Turns air on. |
| Flow
attenuation: |
The process of reducing
the peak flow rate in a collection system or of redistributing a proportion
of the flow already in a collection system. |
| Flow control: |
A method whereby normal
sewer flows or a portion of normal sewer flows are blocked, retarded,
or diverted (bypassed) within certain areas of the sewer collection
system. |
| Flow
reduction: |
The process of decreasing
flows into a collection system or of removing a proportion of the
flow already in a collection system. |
| Flow simulation: |
The replicating of
flows in surface water or combined collection systems using a dynamic
digital model. |
| Flow
split: |
Location where wastewater
exits a manhole through more than one pipe. Also refers to a high
point in the sewer system that causes wastewater to flow away from
the manhole in more than one direction. |
| Fluid
jet cut: |
See jet
cutting. |
| Fluid-assisted
boring/drilling |
A type of guided
boring technique using a combination of mechanical drilling and
pressurized fluid jets to provide the soil cutting action. |
| Fluorescein
dye |
A potent Kelly-green
fluorescent water dye used to "color" waste streams and identify their
flow paths (flow path verification). |
| Fold
& form lining: |
Method of pipeline
rehabilitation in which a liner is folded to reduce its size before
insertion and reversion to its original shape by the application of
pressure and/or heat. See also Lining
with Close-Fit Pipes. |
| Fold and
Form Pipe: |
A pipe rehabilitation
method where a plastic pipe manufactured in a folded shape of reduced
cross-sectional area is pulled into an existing conduit and subsequently
expanded will. pressure and heat. The reformed plastic pipe fits snugly
to and takes the shape of the ID of the host pipe. |
| Force
main: |
A pipeline that conveys
sanitary, combined or stormwater flow under pressure from a pumping
(or lift) station to a discharge point. |
| Forward
rotation: |
The clockwise rotation
of the auger as viewed from the machine end. |
| Fouling: |
An accumulation of
deposits. This term includes accumulation and growth of marine organisms
on a submerged metal surface and also includes the accumulation of
deposits (usually inorganic) on heat exchanger tubing, |
| Foundation
drain: |
A pipe or series of
pipes which collect groundwater from the foundation or footing of
structures and discharge it into sanitary, storm, or combined sewers,
or to other points of disposal for the purpose of draining unwanted
waters away from such structures. |
| Fracture
mechanics: |
A quantitative analysis
for evaluating structural reliability in terms of applied stress,
crack length, and specimen geometry. |
| Fractures: |
Cracks visibly open
along the length and/or circumference of the conduit with the pieces
still in place. |
| Frame
ring: |
In a manhole, it
is the metal frame which supports the cover. |
| Frame:
|
A cast iron unit at
the ground surface that provides entry into the manhole. |
| Free
boring: |
To bore or drill
without the use of casing
installed at the same time as the hole is cut. Not recommended for
use with augers. |
| Front
drive: |
See drive
chuck. |
|
|
|
| Gallons
per minute: |
US customary unit
to measure liquid volume discharge rate. One gallon per minute equals
0.063 liters per second. (abbrev. GPM). |
| Galvanic
cell: |
A cell consisting of
two dissimilar metals in contact with each other and with a common
electrolyte (sometimes refers to two similar metals in contact with
each other but with dissimilar electrolytes; differences can be small
and more specifically defined as a concentration cell). |
| Galvanizing
(spelter coating): |
A plating for iron
and steel composing primarily of zinc. It may be applied electronically
or by dipping the pipe or casing in molten zinc (the fumes are poisonous
to breathe). |
| General
corrosion: |
Corrosion in a uniform
manner. |
| Geographical
Information System (GIS): |
A computer software
system designed to store,manipulate, analyze, and print geographically
referenced information. |
| Gloves: |
Gloves (cloth, rubber
& leather) used by operators, crew members and tracking locator operators
that provide maximum protection against electrical shock if properly
used. |
| Gradation: |
Sieve analysis of
aggregates. |
| Grade: |
The elevations shown
on plans and/or survey grade stakes for the installation of the carrier
pipe. It is occasionally to give elevations for casing. In most cases,
it is given to the flow line but can also be given to the top of the
pipe or casing.
|
| Gradient: |
See Grade. |
| Grain: |
A portion of a solid
metal (usually a fraction of an inch in size) in which the atoms are
arranged in an orderly pattern. The irregular junction of two adjacent
grains is known as a grain boundary; also a unit of weight, 1/7000th
of a pound; also used in connection with soil particles i.e. = grain
of sand. |
| Granular: |
Technical term referring
to (the uniform size on grains of crystals in rock. |
| Graphitization
(graphitic corrosion): |
Corrosion of gray cast
iron in which the metallic constituents are converted to corrosion
products, leaving the graphite flakes intact, Graphitization is also
used in a metallurgical sense to mean the decomposition of iron carbide
to form iron and graphite. |
| Gravity
sewer: |
A sewer that is designed
to operate under open channel conditions (below pipe full capacity)
up to a maximum design flow at which point it will become surcharged. |
| GRC: |
Glass fiber Reinforced
Concrete; a rehabilitation lining. |
| Grease
trap: |
Mechanism in a lateral
that collects grease before it can reach a main line. |
| Grinder
pump: |
See Sewage
grinder pump. |
| Grip: |
Applies travel to
rod or pipe. |
| Ground
|