SHORING,UNDERPINING & SCAFFLODING
SHORING
Shoring is the construction of a temporary structure to support temporarily an
unsafe structure . These render a lateral support to walls and used under
following conditions
 When a wall shows sign of bulging out due to bad workmanship
 When a wall cracks due to unequal settlement of foundation, and cracked
walls needs repairs
 When a adjacent structure is to be dismantled
 When openings are to be made or enlarged in the wall
TYPES OF SHORES
 Raking shores
 Flying shores
 Dead shores
SHORING,UNDERPINING & SCAFFLODING
RAKING SHORES
Inclined members called the rakers are used to give a lateral support to the
wall . It consist of Raker , Wall plate , Needles , Cleats , Bracing , Sole
plate.
Wall plates- 20 -25 cm wide and 5- 7.5 cm thick. Placed vertically against the
Wall and secured by means of needle of-10x7.5 cm, needles further strengthen
by means of cleats nailed directly to wall plate.Rakers about against the
needles . These rakers are inter –connected by struts, to prevent their
buckling . The feet of rakers are connected to an inclined sole plate
embedded in to the ground by means of iron dogs.feet of rakers are further
stiffened near the sole plate by means of hoop iron. The wall plate distribute
the pressure to the wall uniformly.
For tall buildings , the length of rakers can be reduced by introducing Rider
rakers.
If longer length of wall needs support the shoring may be spaced at 3 to 4.5 m
spacing , depends upon requirement. The size of sole plate should be such
that it accommodates all rakers and cleat.
SHORING,UNDERPINING & SCAFFLODING
RAKING SHORES
SHORING,UNDERPINING & SCAFFLODING
FLYING or HORIZONTAL SHORES
Such a shores are used to give a horizontal support to two adjacent, parallel
party walls which have become unsafe due to removal or collapse of
intermediate building. Single flying shore constructed if walls are quite near
to each other upto 9 m. It consist of Wall plate,needles, cleats, struts,
Horizontal shores straining pieces and folding wedges.
When distance between the walls is more , a compound or double flying shore
may be provided. This flying shores have the advantage that building
operations of the ground are not obstructed.
The flying shores should be spaced at 3 to 4.5 m centres along the two walls.
And horizontal braces should be introduced between adjacent shores.
Flying shores are inserted when the old building is being removed , and should
be kept in position till new building is constructed.
SHORING,UNDERPINING & SCAFFLODING
FLYING or HORIZONTAL SHORES
SHORING,UNDERPINING & SCAFFLODING
FLYING or HORIZONTAL SHORES
SHORING,UNDERPINING & SCAFFLODING
DEAD OR VERTICAL SHORES
Such type of shoring consist of vertical member k/as dead shores supporting
horizontal member k/as needles.
Such shoring is provided to serve the following purposes
 To rebuild the defective lower part of the wall.
 To rebuild or deepen the existing foundation
 To make the large opening in the existing wall at lower level.
Needles are of thick wooden sections or of steel. The shores are supported on
sole plates and folding wedges.
The needles are spaced at 1 or 2 m . A minimum three needles are to be used
for an opening. The needle should be suitably braced.
Shores should be removed when the new work has gained sufficient strength ,
but in no case earlier tan 7 days.
The sequence of removal should be , Needle, Strutting from opening. Floor
strutting inside, and raking shore if any. A 2 days interval between removal
operations.
SHORING,UNDERPINING & SCAFFLODING
DEAD OR VERTICAL SHORES
SHORING,UNDERPINING & SCAFFLODING
UNDERPINNING
The process of placing a new foundation under an existing one or
strengthening an existing foundation is called underpinning of foundations.
UNDERPINNIG SERVES THE FOLLOWING PURPOSES
 To strengthen the shallow foundation of existing building when a building
with deep foundation is to be constructed adjoining it.
 To strengthen the existing foundation which has settled and caused the
cracks in the wall .
 To deepen the existing foundation , resting on poor strata so as to rest it on
the deeper soil strata of higher bearing strength.
 To construct the basement in the existing building.
SHORING,UNDERPINING & SCAFFLODING
METHODS OF UNDERPINNING
 PIT METHOD
 PILE METHOD






O
PIT METHOD
In this method the entire length of foundation to be underpinned is divided
into sections of 1.2-1.5 m lengths.
One section is taken up at a time. For each section hole is made in the wall ,
above the plinth level and needle is inserted in the hole.
Bearing plates are placed above the needle to support the masonry above it.
The needle is supported on either side of the wall on crib supports and
screw jack.
The foundation pit is then excavated to desire depth and new foundation is
laid. When work of one section is over, The work on alternate section is
taken up in the first round and then remaining sections are taken up.
If the wall to be underpinned is weak ,raking shores may be provided.
SHORING,UNDERPINING & SCAFFLODING
PIT METHOD
SHORING,UNDERPINING & SCAFFLODING
PIT METHOD WITH CANTELEVER NEEDLE
If interior strong column exists , or foundation is to be extend only to one side
cantilever needle beam may be used in place of central needle beam.
Jack is placed between the column and the wall.
If wall is long work is started from middle and extended in both the directions.
The needle beam is removed only when the new foundation has gained the
strength.
SHORING,UNDERPINING & SCAFFLODING
PIT METHOD WITH CANTELEVER NEEDLE
SHORING,UNDERPINING & SCAFFLODING
PILE METHOD
 In this method piles are driven at regular interval along both the sides of
wall. Generally bore holed piles or under rimmed piles may be used..
 Piles are connected with concrete or steel needle , penetrating through the
wall.
 These beams incidentally acts as a pile cap also .
 This method is very much useful in clayey soil , and also in waterlogged
areas. The existing foundation is very much relieved of the load.
SHORING,UNDERPINING & SCAFFLODING
PILE METHOD
SHORING,UNDERPINING & SCAFFLODING
SCAFFOLDING
When the height of wall or structural member of the building exceeds about
1.5 m. , temporary structures are needed to support the platform over which
the workman can sit and carry on the construction.
These temporary structures are constructed very close to the wall, is in the
form of framework , k/as scaffolding.
Scaffolding also needed for repairs or demolition of buildings.
The scaffolding should be strong enough to support workmen and other
construction material placed on the platform supported by scaffolding.
The height of scaffolding goes o increasing as the height of construction
increases.
SHORING,UNDERPINING & SCAFFLODING










COMPONENT PARTS OFSCAFFOLDING
Standards- These are the vertical members of the frame work ,supported on
ground or drum , or embedded into the ground.
Ledgers- These are horizontal members , running parallel to the wall.
Braces- These are the diagonal members fixed on the standards
Putlogs- These are the transverse members placed at right angle to the wall with
one end supported on the ledger and other end on the wall.
Transoms- These are the putlogs whose both ends are supported on the ledgers
This is a member used to Bridge a wall openings, support one end on putlog at
the opening
Bording- These are the horizontal platform to support a workman and material,
these are supported on putlogs
Guard rail- This is a rail provided like a ledger, at working level
Toe board- These are the boards placed parallel to the ledger ,and supported on
putlogs ,to give protection at the level of working platform.
These various components are secured by means of rope lashings ,nails ,bolts
etc.
SHORING,UNDERPINING & SCAFFLODING
TYPES OF SCAFFOLDING
 Single scaffolding or Brick layers scaffolding
 Double scaffolding or Masons scaffolding
 Cantilever or Needle scaffolding
 Suspended scaffolding
 Trestle scaffolding
 Steel scaffolding
 Patented scaffolding
SHORING,UNDERPINING & SCAFFLODING




SINGLE SCAFFOLDING
This consist of single framework of standards,ledgers,putlogs etc.
Constructed parallel to the wall about 1.2 m . The standards are placed at the
2-2.5 m interval.
Ledger connects the standards and are provided at a vertical interval of 1.2
– 1.5 m.
Putlogs are placed at the one end on the ledgers and other end in the hole
left in the wall. At an interval of 1.2-1.5 m.
Such scaffolding is commonly used for brick laying , and is also called the
putlog scaffolding.
SHORING,UNDERPINING & SCAFFLODING
SINGLE SCAFFOLDING
SHORING,UNDERPINING & SCAFFLODING
DOUBLE SCAFFOLDING (MASONS SCAFFOLDING)
In stone masonry it is very difficult to provide holes in the wall to support
putogs . In that case more strong scaffolding is used consist of two two
rows of scaffoldings .
Each row thus forms a separate vertical framework.
The first row is placed at 20 – 30 cm away from wall while other is placed at 1
m distance from first one.
Putlogs are then supported on both the frames
Rakers and cross braces are provided to make scaffolding more strong and
stable.
Such a scaffolding is called independent scaffolding
SHORING,UNDERPINING & SCAFFLODING
DOUBLE SCAFFOLDING (MASONS SCAFFOLDING)
SHORING,UNDERPINING & SCAFFLODING
CANTILEVER SCAFFOLDING (NEEDLE SCAFFOLDING)
These are used under the followings circumstances
 Ground is weak to support the standards
 Construction of upper part of the wall is to be carried out
 It is require to keep the ground , near wall free for traffic.
 It is single or double scaffolding.
 In single scaffolding the standards are supported on the series of needles
taken out through openings or holes in the wall
 In double scaffolding the needles or projecting beams are strutted inside the
floor through openings
SHORING,UNDERPINING & SCAFFLODING
CANTILEVER SCAFFOLDING (NEEDLE SCAFFOLDING)
SHORING,UNDERPINING & SCAFFLODING
SUSPENDED SCAFFOLDINGS
This is the light weight scaffolding used for repair works such as
pointing,painting etc.
The working platform is suspended from the roof by means of wire ropes or
chains. The platform can be raised or lower at any desired level.
TRESTLED SCAFFOLDING
Such type of scaffolding used for painting and repair works inside the room up
to a height of 5 m .
The working platform is supported on the top of movable contrivances such as
ladder, tripod etc.
SHORING,UNDERPINING & SCAFFLODING
STEEL SCAFFOLDING
A steel scaffolding is practically similar to the timber scaffolding except that
the wooden members are replaced by the steel tubes, and the rope lashing
by the steel couplets or fittings .
Such scaffolding can be erected and dismantled rapidly.
It has a higher strength , durability and fire resistance. Initial cost is more but
salvage value is higher .
It is extensively used these days.
PATENTED SCAFFOLDING
Many patented scaffolding , made of steel ae available in the market .
These scaffoldings are equipped with the special couplings,frames etc.
The working platform is supported on braacket which can be adjusted at any
suitable height.
SHORING,UNDERPINING & SCAFFLODING
STEEL SCAFFOLDING
SHORING,UNDERPINING & SCAFFLODING
STEEL SCAFFOLDING