1/9/2023

TEMPORARY WORKS Temporary Works

Prepared By:-
Mohamed Rizal Mohamed Shoring and Falsework
Building Department
UiTM Perak

Shoring Shoring
• Is a form of temporary support which can be
given to existing buildings with the primary There are 3 types of shoring system usually
function to avoid collapse of the structure used:-
• Shoring can be used when walls bulge out, i. Raking Shores
when walls crack due to unequal settlement ii. Horizontal or Flying Shores
of foundation and repairs are to be carried
out to the cracked wall, when an adjacent iii. Vertical or Dead Shores
structure needs pulling down, when
openings are to be newly made or enlarged
in a wall.

Raking Shores
• This shoring
arrangement
transfers the floor
and wall loads to
the ground by
means of sloping
struts or rakers.

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Raking Shores Raking Shores

• It is very important that
• Raking Shoring are placed at 3.0 to 4.5m c/c the rakers are
and can be of single, double, triple or multiple positioned correctly so
raker format. that they are capable of
receiving maximum wall
• Suitable materials are timber structural steel and floor loads.
and framed tubular scaffolding. • The centerline of the
raker should intersect
with the centerline of
the wall or floor
bearing.

Raking Shores Raking Shores

• One raker for each • A four storey building
floor is required and can be shored by this
ideally should be at method if extra
an angle of between member, called a
40º and 70º with the
horizontal; therefore rider, is added.
the number of rakers
which can be used is
generally limited to
three.

Sequence for erecting raking shoring Sequence for erecting raking shoring
1. Carry out site investigation to determine:- 2. Mark out and cut mortices
and housings in wall plate
– Number of shores required
3. Set out and cut holes for
– Bearing capacity of soil and floor
needles in external wall
– Location of underground services

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Sequence for Sequence for

erecting raking shoring erecting raking shoring
4. Excavate to a firm 6. Fix cleats, distance
bearing subsoil and blocks, blinding and if
lay grillage platform necessary cross
and sole plate. bracing over the backs
5. Cut and erect rakers of the shores.
commencing with the
bottom shore.

Horizontal or Flying Shores

• These shore fulfill the same functions as a
ranking shore but have the advantage of
providing a clear working space under the
shoring.
• They can be used between any parallel wall
surfaces providing the span is not in excess
of 12m when the arrangement would
become
uneconomic.

Horizontal or Flying Shores Horizontal or Flying Shores

• Flying Shores are placed at 3.0 to 4.5m c/c • Short spans up to 9 m usually have a single
and can be of a single or double format. horizontal member whereas the larger
• Unsymmetrical arrangements are possible spans require two horizontal shores to keep
providing the basic principles for flying the section sizes within the timber range
shores are complied commercially available.

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Horizontal or Flying Shores

• It is possible with all forms of shoring to build up the
principal members from smaller sections by using
bolts and timber connectors, ensuring all butt joints
are well staggered to give adequate rigidity.
• The site operation for the
setting out and erection of
a flying system are similar
to those enumerated for
raking shoring.

Unsymmetrical flying shores

Unsymmetrical flying shores Horizontal or Flying Shores

• Advantages:
i. Shorter support member
ii.more stable & stronger support
iii.
provide clear unobstructed working space
iv.less intrusion on the surrounding area / adjacent
building
v. Suitable for congested area / cramped area /
urban area – limited space for construction
activities

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Vertical or Dead Shores Vertical or Dead Shores

• The two shore legs
• Used to support dead
loads which act vertically connected over their
downwards. heads by a horizontal
• It consists of a vertical beam or needle.
prop or shore leg with a • The load are transferred
head plate, sole plate by the needle to the
and some means of shore legs and hence
adjustment for down to a solid bearing
tightening and easing surface.
the shore.

Vertical or Dead Shores

• It may be necessary to
remove paving and cut
holes in suspended
timber floors to reach a
suitable bearing surface.
• If a basement is
encountered, a third
horizontal member
called a transom will be
installed.

Sequence of operation
Sequence of operation 2. Fix ceiling struts between
suitable head and sole plates
to relieve the wall and floor
1. Carry out a through site investigation to loads.
determine:- 3. Strut all window openings
– Number of shores required within the vicinity of shores
to prevent movement or
– Bearing capacity of soil and floor distortion of the opening.
– Location of underground services 4. Cut holes through the wall
slightly larger in size than the
needles

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Sequence of operation Falsework

5. Cut holes through • Falsework is any temporary structure used to
ceilings and floors for the support a permanent structure and to hold
shore legs the component in place until its construction
6. Position and level is sufficiently advanced to support itself.
sleepers on a firm base, • Any failure of falsework may lead to the
removing paving if collapse of the permanent structure.
necessary
• This could cause injury or death to those
7. Erect, wedge and secure working on or near to it, as well as loss of time
shoring arrangements and money.

Loads on falsework
Loads can either be permanent actions (self
weight/dead load) or
variable actions (weight of operatives/live load)