P1258896621sVNuC

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WORK SPECIFICATION FOR
FOR GUNITING
By KHAIRUNISA BINTI KHAIRUDDIN AB
03011 DIPLOMA OF CIVIL ENGINEERING
LECTURER Ir.PROF.MADYA. ADNAN BIN ZULKIPLE
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NORMAL GUNITING PROCEDURE
REBOUND
CONSTRUCTION JOINTS
WORKS TEST PANELS
WEEP HOLES
QUALITY CONTROL
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NORMAL GUNITING PROCEDURE
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• Before starting work, the contractor shall submit
  to the engineer for approval a detailed schedule
  of the entire guniting and method statement of
  works.
• Guides shall be set-up to establish good finish
  surfaces.
• Daily site records off all materials delivered to
  the concrete mixer shall be properly maintained
  and made available to the engineer required.
• All gunite shall be cured continously for 7 days
  or by approved curing compound or equivalent.

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REBOUND
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• All rebound and loose materials shall be
  removed by air jets or other means from the
  surface of each layer as work proceeds.
• Rebound shall not be worked into the sprayed
  area or re-used in the works.
• All surfaces which are not to receive gunite
  shall be protected by approved methods.

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CONSTRUCTION JOINTS
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• The type and positions of all construction joints
  shall be approved by the engineer.
• Construction joints shall be formed by placing
  or trimming the sprayed gunite layer to an angle
  of approximately 300.

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WORKS TEST PANELS
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• During the progress of the works, the contractor
  shall provide at least three moulds for
  reinforced test panels of size
• 750mm x 750mm x 100mm thick, rigidly fixed
  alongside the works at locations as required by
  the engineer.
• The moulds shall be sprayed at such time from
  such concrete batches and by such personnel as
  the engineer may direct.
• The test panels shall be stored and cured
  alongside the gunite works and under similar
  conditions.

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WEEP HOLES
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• Before starting works, the Contractor shall
  submit to the engineer for approval a detailed
  proposal for the construction of weep holes.
• The location and spacing of weep holes shall be
  clearly indicated .

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QUALITY CONTROL
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• Method Statement
• ?The contractor shall submit method statement of
  works to the engineer for approval before
  mobilization.
• ?The method statement shall contain details of
  material of specified quality, machines of
  specific model and capacity, operator and
  technician and his CV plus the estimated daily
  output to ensure the works can be completed
  within the scheduled work programme required .
• ?Method statement shall be prepared by
  experienced engineer who has extensive and
  intensive working experience and also is
  knowledgeable about the characteristic, capacity
  and efficiency of the resources available to his
  disposal.
• ?The engineer shall have inspected the side and
  surrounding conditions thoroughly and assesses
  how the specific conditions will effect the
  output of his resources.

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• b)
• At least 9 cubes of trail mix shall be
  carried out to check the strength of the mix
  specified on contract drawings.
• Rebound hammer test also has to be carried
  out on preconstruction test panels at locations
  selected by engineer ( at least 30 points ).
• The contractor has to redesign the mix if the
  results of any cube or any rebound hammer test
  are below the specified strength on the drawing.

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• c)
• For every 300m² of completed gunite works, a
  series of rebound hammer test ( 30 test points
  per series ) has to be carried out to verify the
  strength
• ( 28 day strength ).
• The engineer reserves the right to reject the
  gunite work if the average result test is below
  the specefic strength.
• d)
• gtgtgtgtgt All weep holes shall be marked by red
  paint to show the required effective thickness of
  gunite specified on drawing.

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• e)
• Prior spraying of gunite, the contractor shall
  request inspection by engineer and a photo shall
  be taken to show the thickness markings.
• The engineer reserves the right to reject the
  gunite works if the thickness of gunite is found
  inadequate or the gunite is found porous or low
  strength
• ( less than specified value ).
• Contractor shall bear the full costs and fees
  for the rectification works are detected.///
• The contractor shall engage a specialist
  geothechnical engineer accredited by
  ACEM-/////////////?//????//??IEM to propose
  rectification works, when defective works are
  identified and directed by the engineer.
• The contractor is fully responsible for the
  costs, time delay in works and other incidental
  consequences for the defective works detached.

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• GUNITING OR SHOTCRETE

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Gunite or Shotcrete refers to concrete produced
by the projection of wet sand and cement mixture
onto an area, by means of pressure applied
through a continuously feeding pressure vessel.
Using guniting, concrete can be applied on
irregular, vertical and overhead surfaces. This
application is used commonly to protect slopes
from erosion, as well as structures of large
areas or uneven surfaces.
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Slope protection by gunitingLocation ? Kuala
Lumpur
Rehabilitation of an existing spillway by
gunitingLocation?Pahang
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• GUNITING OF A DIAPHRAGM
• WALL AT BASEMENT CARPARK

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Pouring of mixed guniting material (weight ratio
dependent on client's requirements)into the
guniting pump.
Spraying of guniting material onto the wall at a
pressure of 3 bar.
Our shotcrete team utilises an internal drainage
system by installing Delta-MSonto the wall,
followed by the installationof BRC mesh onto its
surface. Guniting works is then done on the
Delta-MS.
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Periodical condition inspection and assessment
of an existing hotel blockLocation?Kuala Lumpur