Glossary of Piledriving and Foundation Construction Terms
Welcome to the APE Gloassary for piledriving and foundation construction terms. This is a great place to look for terms that you may be unfamiliar with when working with or researching piledriving technologies. This glossary also contains terms unrelated to piledriving, but that are frequently used on and around foundation construction projects. If you have a question or have term that you would like to add and do not know who to call please contact the APE Headquarters in Washington at (800) 248-8498. Business hours are from 8:00 AM to 5:00 PM Pacific Time. For less immediate inquiries, or if you would like an APE sales representitive to get in contact with you, please visit the APE Contact Request Form.
| TERMS | DEFINITIONS |
| Saddle | 1. A channel with flanges down attached to the top of a square pile or timber to serve as a bearing plate for the pipe cap and to which one or more angles may be attached for retaining the pile cap. 2. A frame that locks the hammer in the leads. |
| Safe Load | A load less than that which would cause objectional settlement, with a factor of safety as necessary to provide for variations in material, workmanship and loading. The safe load for a group of friction piles may be less than the sum of the safe loads for the individual piles comprising the group. |
| Safety Line | See Pile Safety Line. |
| Salt Hay | A coarse grass growing in salt marsh areas; used for rough caulking of breast boarding and around cofferdams. |
| Sampling Spoon | See Spoon Blows. |
| Sand | The category of coarse-grained soil whose particles sizes range between about 0.07 mm and 5 mm in diameter. |
| Sand Drains | Vertical sand columns installed to speed drainage and rapid consolidation of marshy land. Also called Sand Pile and Sand Wick. |
| Sand Pile | See Sand Drain. |
| Sash Brace | A horizontal member securing the piles in a bent. |
| Saximeter | Trade name for a device for remote measuring of the stroke of an open-end diesel hammer. |
| Scope of Work | The specific identification of what, to what standards, and where activity is to be accomplished to fulfill an agreement to perform a task and be compensated for said performance to complete a project. |
| Scour | To erode soils such as from a river bank or around and under a pier by the circular orbits or fast flow of water. |
| Screw Pile | A pile with spiral blade fixed on a shaft or a shaped precast pile, which is screwed into ground by a rotating force. |
| Seawall | A work constructed along a shore line of loose mounds or heaps of rubble, or masonry walls supplemented with treated timber, steel or reinforced concrete sheet piling driven into the beach and strengthened by wales and guide and brace pile. Intended as a barrier to prevent the encroachment fo the sea upon the land by direct wave action. See Dike. |
| Seepage | Small quantity of water percolating through a soil deposit or soil structure such as an earth dam. The quantity of subsurface water leaking into a cofferdam or a building's underground (basement) area. |
| Seismic Exploration | The method of determining subsurface soil and rock conditions (without excavation) by inducing a shock wave into the earth and measuring the velocity of the wave's travel through the earth material. This seismic velocity indicates the types of material it travels through. |
| Seisometer | A device for monitoring the direction and intensity of vibration of ground or structures. |
| Set | 1. The net penetration of a pile into the ground per blow or specific series of blows of a pile hammer. 2. The final penetration of a pile or final set, expressed in inches or millimeters per blow. |
| Set-Up | See Freeze. |
| Settlement | 1. The amount of downward movement of the foundation of a structure or a part of a structure, under conditions of applied loading. 2. The downward vertical movement experienced by structures or a soil surface as the underlying supporting earth compresses. |
| Settlement, Gross | Total downward movement of a pile or pile group under applied load. |
| Settlement, Net | Measured settlement of pile at top after removal of test load. |
| Shackle | U-shaped metal fitting with pin for attaching cable or chain lifting device to a load. |
| Shaft Resistance | The static positive soil resistance along the pile shaft. Also called Side Resistance. |
| Shear Strength | The ability of a soil to resist shearing stresses developed within a soil mass as a result of loading imposed onto the soil. |
| Sheave Head Assembly | See Head Block. |
| Sheet Pile | A pile that may form one of a continuous line or row of timber, precast concrete, or steel piles driven interlocked to provide a tight wall to exclude or resist lateral pressure of water, adjacent earth or other materials. |
| Sheet Pile As a Template | Sheet piles that are hoisted into the air and threaded into previously driven sheet piles are using the previously driven sheet pile as a template The purpose of the Pile Safety Line is to prevent the pile from a sudden life threatening fall should the pile come loose of the hammer or vibrator. Sheet piles, once threaded into adjacent sheet piles are no longer free and are supported by the interlocks of the previously driven sheet piles. . In these cases a Pile Safety Line can be removed from the pile once the sheet is threaded, provided the previously driven sheet is at least 50% driven into the ground in order to provide support and serve as a template. |
| Shell | See Helical Shell. |
| Shelling-Up | Act of placing corrugated shell on the core or mandrel before it is set for driving into the ground. See Doodle Hole. |
| Shield | See Drive Cap. |
| Shipworm | See Marine Borer. |
| Shoe Plates | Reinforcing plates added to flanges and possible web of H-section to reinforce the point to improve penetration into dense materials. See Pile Point. |
| Shook Out | Running steel sheet piles up and down in the interlocks to insure they are free sliding before driving. |
| Shoring | 1. Support for the sides of any excavation. 2. Support for structures, especially in underpinning. See Bracing. |
| Side Batter | A batter left or right from the boom direction. |
| Side Channels | A part of a pile hammer fitted to the sides of the hammer which engage the rails of a set of leads to hold the hammer in the leads. Also called Side Guides, Angle Iron Guides, Grooves, Gibs, Jaws, Ways. |
| Side Guides | See Side Channels. |
| Sieve | Pan or tray-like equipment having a screen or mesh bottom; used in laboratory or field work to separate particles of a soil sample into their various sizes. |
| Sight-Feed Lubricator | A lubricator containing view of the oil flow, which is installed in the fluid line to supply oil to lubricate a pile hammer. See Oiler. |
| Silt | A fine residual soil or alluvial sediment of mud or fine soil deposited from running or standing water. Feels velvety, smooth and floury between the fingers. Silt particles range in size from 0.002 to 0.074 mm. |
| Single-Acting Diesel Hammer | See Disesl Hammer, Open End. |
| Single-Acting Hammer | A pile hammer in which fluid lifts the ram on the up stroke and gravity alone acts on the down stroke. |
| Site | The metes and bounds of an area of earth designated for a project. |
| Site Conditions | An overall description of the site for a project; ground cover, relative elevations, surrounding environment, the presence of surface water and the normal water table, soil borings, known history, as well as the available access and egress. See Soil Investigation. |
| Skew Batter | See Compound Batter PIle. |
| Skid Rig | 1. A pile driver rig consisting of a fluid power supply, hoisting apparatus, pile hammer and leads all mounted upon a common sled for movement on skids or rollers. Also called Pile Frame. 2. A soil boring rig on skids for movement by pushing or dragging. |
| Skin Friction | See Friction Pile. |
| Skirt, Hammer | An extension fastened to the sides of a pile hammer to engage the leads of template supported timber, pipe, concrete, or H-pile to keep the hammer centered upon and in vertical alignment with the pile to permit the hammer's operation free hanging. |
| Sleeve, Pipe, Inside | A metal adaptor used to splice pipe by driving the two pipes on the sleeve. An inside sleeve decreases the I.D. at the splice while maintaining the pipe O.D. |
| Sleeve, Pipe, Outside | A metal adaptor used to splice pipe by driving the two pipes into a force-fit sleeve. An outside sleeve increases the O.D. at the splice while maintaining the pipe I.D. |
| Slide Pile | A pile driven into the earth to consolidate the soiul and help to prevent it from sliding down a slope. |
| Slinging Hole | Small hole cut in pile for attachment of shackle for handling. |
| Slip Layer | A viscous liquid (normally a bituminous coating) applied to the pile surface. It is expected to shear under the downward force of settling soil and minimize additional load from downdrag. See Negative Skin Friction. |
| Slow Test | A maintained pile load test with time intervals greater than 20 minutes. See CRP and MLT. |
| Slump | A measure of consistency of fresh concrete. It is made with truncated cone 12 in. high, 4 in diameter at the top and 8 in. diameter at the bottom filled with concrete in three lifts, each lift rodded thoroughly 25 times. The cone is then lifted slowly and the concrete within falls into a slump condition. The height of the concrete in inches deducted from the 12 in. cone height is the slump expressed in inches. |
| Slurry | Mixture of water and clay used in excavated shafts or walls to suspend particles for removal while balancing soil pressure against sloughing. |
| Slurry Trench Wall | A watertight concrete cut-off wall or a combination concrete structural cut-off wall tremie poured in an excavated and fluid (bentonite slurry) filled trench. Also caleld Diaphragm Wall. |
| Socketed Pier or Pile | See Drilled-in-Caisson. |
| Soil Anchor | A high-strength steel tendon installed in the earth with anchoring provision in soil that will resist movement and presstressed against a wall by an anchoring device. |
| Soil Boring | A small diameter hole drilled into the soil for the purposes of obtaining earth samples and exploring the subsurface conditions. |
| Soil Boring Log | The complete record of what was found from drilling one soil exploration hole. |
| Soil Damping | A dynamic soil resistance force that is a direct function of pile velocity. |
| Soil Damping Parameter | Often designated by "J" with a unit of measure of second/ft. According to Smith's definition, soil damping equals J x pile velocity x static soil resitance. |
| Soil Engineer | See Geotechnical Engineer. |
| Soil Fill | See Fill, Backfill. |
| Soil Investigation | A study of the earth in the area of a foundation consisting of sampling, classification, preparation of logs of borings and a report setting forth conclusions and recommendations. It is basic to the design of foudnations and is required by most up-to-date building codes. |
| Soil Plug | Material that rises in open-end pile as it is driven. |
| Soil Sampler | The equipment used to extract soil samples from borings or test pits made in a subsurface investigation. |
| Soil Stabalizations | Treatment of soil to improve its properties; includes the mixing of additives and other means of alteration such as compaction or drainage. Also called Soil Improvement. |
| Soldier Pile | A steel H or WF section driven (or placed in drilled hole) normally vertical at intervals of several feet to hold horizontal lagging, which is installed to retain soil as excavation proceeds. Also called Soldier Beam. |
| Sonic Driver | A machine designed to drive piles using high frequency vibrations in the lower sonic range to cause the pile to resonate. |
| Sounding | A method of examining soil to 20 to 30 ft depth by driving or hydraulically pushing a cone, steel rod or small diameter pipe (gas pipe) into the ground with a hammer or maul. With experience, the movement of the rod or pipe under each hammer blow can give an indication of the approximate types of soils materials which are being penetrated. Also called probing. |
| Spider | See Brace. |
| Spile | A small wooden peg, hence a spile or pile. |
| Spiral Weld Pipe | Strip steel or plate turned into an open pipe with the longitudinal (spiral) joint welded into a tight seam. |
| Splice | The joining of two pile segments. |
| Spliced Pile | A pile composed of two or more segments or equal or different sections secured end to end, to form one piole. See Composite Pile. |
| Spoil | Earth, rock debris, etc to be disposed of. |
| Spoon Blows | The blows of a 140 lb. hammer falling 30 in. onto a 2 in. O.D. x 1 3/8 in. I.D. split-spoon sampler. See N Value. |
| Spotter | See Brace. |
| Spread Footing | An enlarged foundation under a column or load to reduce the total bearing stress per square foot to carry the load directly upon the soil or rock. |
| Spreader Bars | See Brace. |
| Spring Fender | A fender so built that impact is taken up in part by steel springs, plates, or rubber or by elastic bending of the construction. |
| SPT | Standard Penetration Test. See N Value. |
| Spud | 1. A short, strong member driven and then removed to break through a hard crust of material or to make a hole for inserting a pile which is too long for placing directly in the pile driver leads. 2. A movable vertical pipe or H-section placed through a strong frame on a barge to anchor a vessel to the bottom. |
| Spud Clip | Devices bolted to a pile hammer to engage it with and permit it to slide along a spud lead. Sometimes called gib. |
| Spud Lead | A steel wide-flange or H-beam used in place of leads. The hammer engages and slides upon one flange of the beam through the use of spud clips bolted to the hammer. Also called H-beam Lead, Monkey Stick. |
| Spudding | The act of opening a hole through dense material by dropping a driving spud. |
| Spur Dike | See Groin. |
| Spur Pile | See Batter Pile. |
| Stabbing Points, Leads | Fabricated steel points fasened to the very bottom of swinging box leads to facilitate rigidly positioning the bottom of th elead by stabbing the points into the ground. |
| Staking Out | The surveying act of putting stakes in the ground where the piles are to be driven. |
| Standard Penetration Test | See N Value. |
| Staylathing | Usually two horicontal timbers placed on opposite sides of a row of piles and drawn together by bolts to pull the piles into line. |
| Steam Lead | See Box Lead. |
| Steel H-Pile | A rolled-steel section with web and flanges nearly the same thickness. The width and depth are approximately equal. Also called H-Beam. |
| Steel Pipe Pile | Pipe in any wall thickness or diameter; it may be driven closed end or open end. Also called Tube Pile. |
| Step-Tapered Pile | A cast-in-place concrete pile formed by installing successively larger sections of corrugated shell or thin-wall pipe; ordinarily installed with a mandrel that bears on a connector between lengthes. A cuneiform pile. |
| Stiffeners, Web | Plates welded between flanges of a structural shapes to reinforce against concentrated loading, as for testing. |
| Stinger | See Brace. |
| Stone Columns | Soarse crushed stone or gravel injected into poor bearing soil by jetting and vibro-displacement to improve carrying capacity. See Vibroflotation. |
| Stope | An excavation made into the ground in a series of steps or benches. |
| Stoppers | Plates fastened between flanges of an H, or other steel pile at right angles to the vertical axis, for the purpose of increasing the pile's bearing area. See Lagged Pile. |
| Strapping | See Banding. |
| Strike | The direction of a geologic boundary exposed at the ground surface relative to the north. See Dip. |
| Striker Plate | See Anvil. |
| String Line | A cord used as a guide for straightness. |
| Stringer | A member at right angles to, and resting on or clamped to pile caps, forming a support for the superstructure. |
| Stroke | The distance traveled up or down by the ram of a pile hammer. |
| Strut | 1. A compression member extended horizontally from bent to bent, or pile to pile in a bent, and serving as a stiffening member. 2. A compression member extending from waler to support point which may be another waler or the ground. 3. See Brace. |
| Sump | Small excavation or pit provided in a low point of construction to serve as a collection basin for surface water and near surface underground water. |
| Sump Pump | Usually a self-priming pump capable of handling water with high mud content. |
| Super Kong | APE Model 600 Vibratory Driver/Extractor is the world's largest vibratory pile driver/extractor. |
| Surveyor | The professional responsible for determining and locating in the field the horizontal and vertical coordinates for the project, as defined by the design engineer. |
| Swage Pile | A thin wall pipe pile with bottom closed by a slightly tapered precast point. Driving is done by a mandrel on the point, dragging the pile down -- with an assist from a shoulder on the exact length mandrel. See Caudill Drive Point Pile. Also called core drive pile. |
| Swinging Leads | See Leads, Swinging. |
| Swivel Leads | See Leads, Cardonic. |
