- Tieback (geotechnical)
A tieback is a horizontal wire or rod, or a helical anchor used to reinforce retaining walls for stability. With one end of the tieback secured to the wall, the other end is anchored to a stable structure, such as a concrete deadman which has been driven into the ground or anchored into earth with sufficient resistance. The tieback-deadman structure resists forces that would otherwise cause the wall to lean, as for example, when a seawall is pushed seaward by water trapped on the landward side after a heavy rain.
Grouted tiebacks can be constructed as steel rods drilled through a concrete wall out into the soil or bedrock on the other side. Grout is then pumped under pressure into the tieback anchor holes so that the rods can utilize soil resistance to prevent tieback pullout and wall destabilization.
Helical anchors are screwed into place. Their capacity is proportional to the torque required during installation. This relationship is in accordance with the equation Qt = kT where Qt is the total tensile resistance, k is an empirical constant and T is the installation torque. These anchors are installed either for small loads in short sections (as pioneered by the AB Chance company) or for larger loads and in long continuous lengths (as pioneered by Helical Solutions Inc.).
Topics in geotechnical engineering Soils Soil properties Soil mechanics Geotechnical investigation Laboratory tests Field tests Foundations Retaining walls Slope stability Earthquakes Geosynthetics Instrumentation for Stability Monitoring
Wikimedia Foundation. 2010.
Look at other dictionaries:
Tieback — may refer to: Tieback (geotechnical), a method of supporting retaining walls Reconciliation, Relating Back Tieback (subsea), is a connection between a new oil and gas discovery and an existing production facility, improving the economics of… … Wikipedia
Cone penetration test — A CPT truck operated by the USGS. The cone penetration test (CPT) is an in situ testing method used to determine the geotechnical engineering properties of soils and delineating soil stratigraphy. It was initially developed in the 1950s at the… … Wikipedia
Newmark's sliding block — The Newmark s sliding block analysis method is an engineering method used to calculate the permanent displacements of soil slopes (also embankments and dams) during seismic loading. It is also simply called Newmark s analysis or Sliding block… … Wikipedia
Deep foundation — A deep foundation installation for a bridge in Napa, California, United States … Wikipedia
Dynamic load testing — of piles is a fast and effective method of assessing foundation bearing capacity that requires instrumenting a deep foundation with accelerometers and strain transducers and analyzing data collected by these sensors. The procedure is based on the … Wikipedia
Clay — For other uses, see Clay (disambiguation). The Gay Head cliffs in Martha s Vineyard consist almost entirely of clay. Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic… … Wikipedia
Landslide — This article is about the geological phenomenon. For other uses, see Landslide (disambiguation). Rockslide redirects here. For the comic book character, see Rockslide (comics). Computer simulation of a slump landslide in San Mateo County,… … Wikipedia
Slurry wall — excavator A set of Slurry wall guide walls before excav … Wikipedia
Water content — Soil composition by phase: s soil (dry), v void (pores filled with water or air), w water, a air. V is volume, M is mass. Water content or moisture content is the quantity of water contained in a material, such as soil (called soil moisture),… … Wikipedia
Crosshole sonic logging — (CSL) is a method to verify the structural integrity of drilled shafts and other concrete piles. The CSL method is considered to be more accurate than sonic echo testing in the determination of structural soundness of concrete within the drilled… … Wikipedia