Notes on introduction and design of TEMPORARY WORKS

1. BTECH
TOPIC -TEMPORARY WORKS
Introduction
Temporary works in construction refer to any structures, equipment, or systems that are used
during the construction process but are not meant to be a permanent part of the finished project.
Some examples of temporary works in construction include:
1. Formwork: As mentioned previously, formwork is a temporary structure used to hold and
shape wet concrete while it cures.
2. Falsework: Falsework is a temporary structure used to support an existing structure or a
new structure during construction.
3. Shoring: Shoring is a temporary system of supports used to prevent the collapse of a
structure during construction or repair.
4. Scaffolding: Scaffolding is a temporary structure used to provide access and support for
workers during the construction or repair of a building or other structure.
5. Temporary power and lighting: Temporary power and lighting systems are used to
provide power and light to the construction site during the construction process.
6. Temporary drainage: Temporary drainage systems are used to divert water away from the
construction site during the construction process.
7. Temporary access: Temporary access systems such as roads, bridges, and ramps are used
to provide access to the construction site during the construction process.
8. Temporary protection: Temporary protection systems such as site hoardings, fencing and
screens are used to protect the workers and the public from the construction site.
SHORING
Shoring is a temporary construction technique used to support an existing structure or a new
structure during construction, repair, or renovation. It is used to prevent the collapse of a
structure due to the removal of load-bearing elements or the addition of new load-bearing
elements.
Shoring systems can be either vertical or horizontal. Vertical shoring is used to support the
weight of a structure from the bottom up, while horizontal shoring is used to support the weight
of a structure from the sides.
TYPES OF SHORING
a) RAKING SHORE
b) DEAD SHORE
c) FLYING SHORE

2. RAKING SHORE
In this method, inclined members, called rakers are used to give lateral support to the wall as
shown in Fig.1
Rakers or inclined members,
• Wall plate,
• Needles,
• Cleats,
• Bracing, and
• Sole plate

3. The wall plate (20 to 25 cm wide and 5 to 7.5 cm thick) is placed vertically along the face of
the wall and is secured by means of needles.
These needles (10 cm x 7.5 cm) penetrate the wall by about 10 to 15 cm. In order that the needles
do not get sheared off due to the thrust of the raker, the needles are further strengthened by
means of cleats which are nailed directly to the wall plate.
Rakers about against the needles in such a way that the centerline of the raker and the wall meet
at the floor level. Thus, there will be one raker corresponding to each floor. These rakers are
inter-connected by struts, to prevent their buckling.
An inclined sole plate is embedded into the ground on which the feet of rakers are connected.
The 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.
The following points are keep in mind when using Raking shores:
1. Rakers should be inclined to the ground by 45° to 75°, but 45° is more effective. The Top
of raker should not be inclined steeper than 75°.
2. For tall buildings, the length of raker can be reduced by introducing rider raker.
3. Rakers should be properly braced at intervals.
4. The size of the rakers should be decided on the basis of anticipated thrust from the wall.
5. The centre line of a raker and the wall are maintained at the same level of floor.
6. If longer length of the wall needs support, shoring may be spaced at 3 to 4.5 m spacing,
depending upon the requirements.
7. The sole plate should be properly embedded into the ground, at an inclination and should
be of proper sectiod. The sole plate should be sufficient widen so that it can easily
support all the rakers, and a cleat provided along the outer edge.
8. Wedges should not be used on sole plates since they are likely to give was under
vibrations which are likely to occur.
Flying or Horizontal Shores
Flying shores are a support system which provides horizontal support to two parallel party walls
when removal or collapse of the intermediate building takes place.
All types of shoring system of supporting the unsafe structure in which the shores do not reach
the ground are the flying shores. If the walls are quite near to each other (distance up to 9 m),
single flying shore (Fig.2)

4. In this system operations of the building in the ground are not obstructed.
The following points should be kept in mind while connecting the flying shores:
1. The center lines of flying shore and struts and those of the walls should meet at floor
levels of the two buildings. If the floor level are different, the horizontal shore should be
placed either mid-way between the levels of the two floor of equal strength, or it should
be placed at the level of weaker floor.
2. The struts should preferably be inclined at 45°. In no case should this inclination exceed
60°.
3. Single shores should be used only up to 9 m distance between walls. For greater distance,
double shores should be provided. In that case, both the horizontal shores should be
symmetrically placed with respect to the floor levels.
4. The flying shores should be spaced at 3 to 4.5 m centers, along the two walls; and
horizontal braces should be introduced between adjacent shores.
5. In this system, various members of the shoring are determined by using large factor of
safety because it is uncommon to assess the actual loads.
6. When there is a structural gap between two building due to removal of old building then,
flying shore are inserted and removed after construction of new structure.
Dead or Vertical Shores
Dead shore is a shoring system in which a dead shore in the form of vertical member support
horizontal needles which transfer the load of the wall, roofs and floors etc.
The needles transfer the load of the wall etc., to the dead shores.
This type of shoring is use for the following purposes:

5. • To rebuild the defective lower part of the wall.
• To rebuild or deepen the existing foundation.
• To make large opening in the existing wall at lower level for underpinning and such type
of work.
First of all holes are made in the wall at calculated height. Then needles made of thick wood or
steel sections are inserted into the holes and are supported on vertical posts or dead shores on
both sides. This type of shoring system is keep away from the wall for easy to do repair work.
Dead shores are supported and anchor on plates and folding wedges.
The following points are to be considered for vertical shore:
• The section of needle and dead shores should be perfect to transfer the load, which can
estimate with a fair degree of accuracy.
• The needles are spaced at 1 to 2 meters. A minimum of three needles should be used for
and opening.
• The needles should be suitably braced.
• Sometimes opening is made in an external wall, that case the length of the outer shores is
longer than inner ones.
• The dead shores are stable and rest on sole plates. Folding wedges should be inserted
between the two. It is preferable to use one single sole plate between dead shores in a
raw.
• The floors should be suitably supported from inside.
• In case the external wall is week then dead shore is not provided, in that case raking
shores are provided.
• After 7 days of completion of the work shoring is removed making sure that new work
has gained sufficient strength. The new work should have proper strutting.

6. • The sequence of removal should be (i) needles, (ii) strutting from opening, (iii) floor
strutting inside, and (iv)raking shore if any at the interval of 2 days.
UNDERPINNING
Underpinning is a technique used to strengthen and stabilize the foundation of an existing
building or structure. It is typically used when the existing foundation is not adequate to support
the loads imposed on it, or when the soil beneath the foundation has been compromised.
There are several methods of underpinning, including:
1. Mass concrete underpinning: This method involves excavating the soil beneath the
existing foundation and pouring new concrete to create a new, stronger foundation.
2. Pile underpinning: This method involves driving steel or concrete piles into the soil
beneath the existing foundation to provide additional support.
3. Beam and base plate underpinning: This method involves installing steel beams beneath
the existing foundation and connecting them to concrete pads to provide additional
support.
4. Mini-pile underpinning: This method involves installing small-diameter piles beneath the
existing foundation to provide additional support.
5. Grout injection underpinning: This method involves injecting grout into the soil beneath
the existing foundation to fill voids and provide additional support.

7. TYPES OF UNDERPINNING
WALL UNDERPINNING
Wall underpinning is a technique used to strengthen and stabilize the foundation of an existing
building or structure when the wall is not able to support the loads imposed on it. It is typically
used when the existing foundation is not adequate to support the loads imposed on it, or when the
soil beneath the foundation has been compromised.
There are several methods of wall underpinning:
1. Mass concrete underpinning: This method involves excavating the soil beneath the
existing foundation and pouring new concrete to create a new, stronger foundation.
2. Pile underpinning: This method involves driving steel or concrete piles into the soil
beneath the existing foundation to provide additional support.
3. Beam and base plate underpinning: This method involves installing steel beams beneath
the existing foundation and connecting them to concrete pads to provide additional
support.
4. Mini-pile underpinning: This method involves installing small-diameter piles beneath the
existing foundation to provide additional support.
5. Grout injection underpinning: This method involves injecting grout into the soil beneath
the existing foundation to fill voids and provide additional support.
6. Brick and stone underpinning: This method involves excavating beneath the wall,
removing the original foundation and rebuilding it with stronger materials such as brick
or stone.

8. COLUMN UNDERPINNING
Column underpinning is a technique used to strengthen and stabilize the foundation of an
existing building or structure when the load-bearing capacity of the existing column foundation
is insufficient. It is typically used when the existing foundation is not adequate to support the
loads imposed on it or when the soil beneath the foundation has been compromised.
There are several methods of column underpinning, including:
1. Conventional Underpinning: The conventional method of underpinning involves
excavating the soil beneath the existing foundation and pouring new concrete to create a
new, stronger foundation.

9. 2. Pile Underpinning: Pile underpinning involves driving steel or concrete piles into the soil
beneath the existing foundation to provide additional support.
3. Base plate underpinning: This method involves installing steel plates beneath the existing
column foundation and connecting them to concrete pads to provide additional support.
4. Mini-pile underpinning: This method involves installing small-diameter piles beneath the
existing foundation to provide additional support.
5. Grout injection underpinning: This method involves injecting grout into the soil beneath
the existing column foundation to fill voids and provide additional support.