What is a hammerhead pier?
What is a hammerhead pier?
Hammerhead or Cantilevered Piers Hammer head pier, which is also termed as solid shaft pier, has a single solid concrete cross section upon which a cap is placed. This type of pier is used to support steel girder or precast prestressed concrete superstructures.
How is a pier constructed?
Pier, in building construction, vertical loadbearing member, such as an intermediate support for adjacent ends of two bridge spans. In foundations for large buildings, piers are usually cylindrical concrete shafts, cast in prepared holes, but in bridges they take the form of caissons, which are sunk into position.
How many types of piers are there?
There are several ways of defining pier types. One is by its structural connectivity to the superstructure: monolithic or cantilevered. Another is by its sectional shape: solid or hollow; round, octagonal, hexagonal, or rectangular.
Which type of pier permits the saving in the quantity of concrete?
Cellular, trestle, hammerhead, and single-column types use reinforced concrete and are suitable for heights above 6 m and spans over 20 m. The cellular type permits saving in the quantity of concrete, but usually requires difficult shuttering and additional labour in placing reinforcements.
How do you calculate pier size?
To determine the load of a deck pier, you must take half the length of the joist span multiplied by half the length of the beam span (measured from pier to pier). This number is then multiplied by 50, which is the 40 psf live load, 10 psf dead load mentioned earlier.
What is the minimum top width of pier?
Minimum thickriess provided to the pier cap is 225 mm for spans of up to 25 m, otherwise 300 mm. Typical shapes of piers commonly used in practice are as shown in Fig. 2.1.
Why is it called a pier?
A pier is a structure built on pillars that begins on land and extends into the ocean. A supporting pillar in a bridge or an arch is also called a pier. Pier comes from the Old French word, pire, which means a breakwater.
What are pier supports called?
The simplest cross section of the pier is square, or rectangular, but other shapes are also common. In medieval architecture, massive circular supports called drum piers, cruciform (cross-shaped) piers, and compound piers are common architectural elements.
What are the requirements of good pier?
It should effectively transfer loads from Superstructure to foundation without failure. It should have pleasant appearance. Its design should be simple. The piers should be durable against weathering, impacts and corrosion.
What is the function of a pier?
A pier is a raised structure that rises above a body of water and usually juts out from its shore, typically supported by piles or pillars, and provides above-water access to offshore areas. Frequent pier uses include fishing, boat docking and access for both passengers and cargo, and oceanside recreation.
What influences pier size?
Three things affect the number and the size of piers you use: the way you frame the deck, the weight the deck is designed for, and the load-bearing capacity of the soil.
How big is a helical pier?
Circular tapered plates (helices) are welded to the center of the shaft. Helix diameters can range between 6″ – 48″ with a thickness of 3/8″ – 1″. Helix pitch will range from 3″ – 6″. Galvanized or bare steel options available.
What kind of Pier is hammer head pier?
Hammer head pier, which is also termed as solid shaft pier, has a single solid concrete cross section upon which a cap is placed. This type of pier is used to support steel girder or precast prestressed concrete superstructures. It is mostly constructed in urban areas where space limitation is a concern.
How big is a Hammerhead Pier on spread?
This example illustrates the substructure design of a hammerhead pier cap with a single column supported on a spread footing on rock for a three span precast prestressed box beam bridge. The bridge has spans of 85’-3”, 86’-6” and 85’- 3” resulting in equal lengths of the modified AASHTO BII-48 box beam in all spans.
What kind of structure is a pier bridge?
Piers (columns) are structures that support the superstructure, and are used for bridges with two or more spans. The superstructure loads are transmitted through the bearings and pier caps, but in some cases, the pier caps and the superstructure are integrated together with no bearings (integral pier bridges).
What kind of Pier is a pile pier?
Pile pier is the modification of multicolumn bent and used for the type of bent on low height and short span structure. So, pile pier or pile bents are specified when the ground is unstable and the low piers are required. Trestle pier is composed of column with bent cap at the top.