Docstoc

BRIGHTON JETTY

Document Sample
BRIGHTON JETTY Powered By Docstoc
					BRIGHTON JETTY




              LEIGH DAWSON
           PETER HEFFERNAN
               HISTORY
 Original jetty built in 1886
 Constructed of timber supported on timber
  piles and crossheads.
 206 metres long.
 Tee-head at western end.

 Destroyed on 24 May 1994 by heavy
 storms.
DESTRUCTION OF JETTY
             HISTORY (2)
 New jetty constructed in 1995/96.
 Deck, beams, crossheads & piles
  constructed of concrete.
 209 metres long with jetty head.
 Mobile phone tower placed at centre of
  jetty head.
NEW JETTY
   AIMS OF PRESENTATION
 Model jetty deck under following
 conditions:
   Dead & live load distributed over entire deck.
   Dead load distributed over entire deck, live
    load distributed on half of deck.
 Model one concrete pile under following
 conditions:
   Stresses due to normal loading.
   Displacements in z direction.
             ASSUMPTIONS
 Concrete Strength f’c = 50 MPa
    (AS3600, Table 4.3: in tidal or splash zone,
    Exposure classification C)
   Fixed at abutments.
   Live load 5 kPa (AS1170.1, Table 3.1, C3).
   Dead Load 7.6 kPa.
   Deck not constructed as a T-beam, but is a
    plate connected to two parallel beams.
DECK LAYOUT
     MODELLING OF DECK
 Constructed by using 23 deck sections,
  each of length 8.54 m long.
 Consists of a deck connected to two
  beams that run below and in the same
  direction as the deck.
 These sit on cross heads that are in turn
  connected to two piles.
MODELLING OF DECK
MODELLING OF DECK
            DECK MODEL
 First analysis involves the dead & live load
  distributed over the entire deck.
 Analysed using concrete and also wood,
  to compare roughly how the jetty would
  have performed prior to being destroyed.
 Conclusions: stresses remained
  approximately the same, displacements
  were different but displacement shape was
  the same.
DECK DISPLACEMENTS
DECK STRESS 11
DECK STRESS 22
BEAM DISPLACEMENTS
BEAM STRESSES
            DECK MODEL
 Second analysis involved the dead load
  being distributed over entire deck and live
  load distributed on one half of the deck
  only.
 Analysed for concrete only.
 Conclusions: Displacements greater on
  the side with the live load applied, but
  stresses slightly less.
DECK DISPLACEMENTS
DECK STRESS 11
DECK STRESS 22
MODDELLING OF PILE
              PILE MODEL
 octagon cross section with a width of 406
    millimetres.
   50 MPa concrete
   Length: 13.5 metres
   Driven into sand assumed pressure onto
    pile of 17 kN/m
   Load on top of pile taken as 16.6Kpa
               PILE MODEL
 Displacement of the
  pile into the sand
              PILE MODEL
 Brick Stress 11 & 22
                 PILE MODEL
 Plate Stress
MOBILE PHONE TOWER
    MOBILE PHONE TOWER
 Analysis is difficult.
 It is expected that there will be a greater
  concentration of stresses and
  displacements around the base of the
  phone tower.
 Some resistance to these will be provided
  by the thicker deck section.
      THAT’S ALL FOLKS!



 Thankyou and we hope you enjoyed the
 presentation brought to you by a concrete
 deck, a concrete beam and 16 kPa!

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:10
posted:10/8/2011
language:English
pages:29