Foundations discussions

Replies

• 

  CIVILPRINCESS

  now that we've seen the primitive foundation which is basements now let us see what are the types of foundations.
  
  types of foundations:
  
  1. shallow foundations
  isolated column footing ( square, rectangle, circular)
  continuous wall footing
  strip footing
  combined footing
  mat/raft footing
  
  2. deep foundations
  piles ( concrete, steel, timber, composite piles)
  sheet piles
  diaphragm walls
  caissons
• 

  maria flor

  What is a pile foundation??? what's the purpose of having this type of foundation in building???
• 

  CIVILPRINCESS

  pile foundations are deep foundations provided to depths around 30m and more.
  It is used where the good soil (harder strata) is at higher depth (10 or 15 m) or soil having low bearing capacity and low shear strength. Pile is also used for tall structures. In pile foundation load coming from the super structure is taken by pile cap and equally distributed in no. of piles. PIle transfers this load in to the soil. Major load from super structure is resisted by friction between pile and soil.
  
  
• 

  maria flor

  In building Burj, did they use pile foundation???
• 

  CIVILPRINCESS

  yeah they used. 😀
  
  almost all high rise these days make use of piles for effective load transfer. 😀
• 

  CIVILPRINCESS

  check out the chief structural engineer of burj-william f baker's interview in CE 😁
  #-Link-Snipped-#
  
  he says "Foundations for the Burj Dubai were fairly conventional. Because of the way the tower spreads as it nears the base, the load is spread over a larger area. So, in the end, the foundations are not that much different than they are in a much smaller building. Essentially, it has 194-1.5m diameter piles, each of which is rated at 3,000 tonnes, and supports a 3.7 meter thick concrete mat, or as the British would say, raft."
• 

  maria flor

  What type of foundation is used in order to resist earthquake???
• 

  CIVILPRINCESS

  normally piles are like columns only that they are beneath the ground surface. the load is transferred in two ways.
  1. by friction between the surface area of piles and the soil.
  2. by direct load transfer to the harder strata underneath.
  
  so this piles are to be connected as a group this is done by the use of a raft or a mat. this is nothing but a layer of concrete (reinforced) over the graded soil. this raft will get connected with the pile caps of the piles. the pile caps are just a cover sort of thing at the top of the pile. so this is the basic working of a pile foundation.
  
  
• 

  CIVILPRINCESS

  maria flor

  What type of foundation is used in order to resist earthquake???

  that i don't think there is any particular foundation for that. depends on soil i guess..
  
  anybody else got answer to that ?
• 

  maria flor

  How would engineers be able to know if there is hard underneath strata???by soil testing???
• 

  CIVILPRINCESS

  yeah i guess the soil information report (SIR) would give those details 😀
• 

  maria flor

  What is a driven pile foundation??? Is this another type of pile foundation???
• 

  CIVILPRINCESS

  driven piles are nothing but the precast piles. they're fabricated on the ground and then driven into the ground with the use of drop hammers fitted to a frame. the drop of the hammer is larger than the pile depth.
  
  the other type of pile is cast insitu. it is made by boring a deep hole to the required depth and then placing the reinforcement cage and then concreting.
  
  these are the basic two types.
• 

  CIVILPRINCESS

  types of piles:-
  
  based on the method of load transfer:-
  1. friction piles
  2. end bearing piles
  3. combination of fixed and end bearing piles.
  
  
  
  based on function:-
  1. batter piles
  2. anchor piles
  3. dolphin piles
  4. fender piles
  5. sheet piles
  
  
  
  
  
  
  
  based on materials used:-
  
  1. concrete piles
  2. steel piles
  3. timber piles
  4. composite piles
  
  based on method of installation:-
  
  1. cast insitu (bored or augured)
  2. driven piles (hammered)
  3. screw piles
  
  this is all the types of piles that i can remember. i'll update if i remember any more. others too add if i've left any. 😀
  
  -CP
• 

  anuraadha

  Base isolation technique is adopted to prevent the building during earthquake. In this method series of bearing pads made of lead and rubber is fixed between foundation and building.
  Of late Earthquake Resistant Foundation system is used in which the horizontal movement and vertical acceleration is minimized when prefabricated neoprene padding is bolted to the sill-pad foundation. As a result, the building remains stationary while nature takes its course, and the earth expends its energy underneath.
• 

  Anant Jalgaonkar

  maria flor

  What type of foundation is used in order to resist earthquake???

  Well one cannot specify any type of foundation in case of earthquake(EQ), foundations are designed for seismic forces!! Generally when soil is poor Piles usually performs well in a seismic case.
• 

  gopaldeshpande

  what are the types of tests for piles?
• 

  Kavi Desai

  The isolated footing is one of the most popular and simplest types of foundation used worldwide. Foundations are very important to the building. Ultimately the entire load of the building is transferred to ground through the foundation.
  Isolated footings are most commonly used footings for Reinforced cement concrete column because it is simple and most economical. An isolated footing is used to support a single column.
  This type of footing is used when
  

  • Columns are not closely spaced.
  • Loads on footings are less.
  • The Safe bearing capacity of the soil is generally high.

  For more details, you can refer the article: #-Link-Snipped-#