| Term |
Definition |
|
| Fabric |
Used to describe the physical material from which a pipe is made: vitrified clay; brick; concrete, for example. |
| Face |
Wall of the entrance pit into which the bore is made. |
| Face stability |
Stability of the excavated face of a tunnel or pipe jack. |
| Fairings |
Molding features at the ends at the ends of pipes, usually of varying dimensions to the main pipe, to facilitate easy jointing. |
| Fatigue |
The phenomenon leading to fracture under repeated or fluctuating stresses having a maximum value less than the tensile strength of the material. |
| Fatigue Strength |
The stress to which a material can be subjected for a specified number of fatigue cycles. |
| Feet |
US customary unit for measuring length. One foot equals 304.8 mm; or 0.3048 meters. (abbrev. ft). |
| 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). |
| 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 sit |
| 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 flar |
| 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 |
| 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 stru |
| 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 |
A cast iron unit at the ground surface that provides entry into the manhole. |
| Frame ring |
In a manhole, it is the metal frame which supports the cover. |
| 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. |
