The document provides specifications for lime mortar and excavation and foundation work. It discusses the properties and types of lime mortar, including non-hydraulic and hydraulic lime mortar. It also outlines the process of excavation, including depth, methods such as open cut and braced excavation, and backfilling. Measurements for excavation work and appropriate equipment for different soil conditions are also specified.

1. SPECIFICATIONS AND ESTIMATIONS
MATERIAL- LIME MORTAR
ITEM OF WORK – EXCAVATION AND FOUNDATION

2. LIME MORTAR
Lime mortar is a type of mortar composed of lime and
an aggregate such as sand , mixed with water. It is one of
the oldest known types of mortar.
With the introduction of ordinary portland cement (OPC)
during the 19th century the use of lime mortar in new
constructions gradually declined, largely due to portland's
ease of use, quick setting, and high compressive strength.
However the soft, porous properties of lime mortar provide
certain advantages when working with softer building
materials such as natural stone and terracotta. For this
reason, while OPC continues to be commonly used in brick
and concrete construction, in the repair and restoration of
brick and stone-built structures originally built using lime
mortar, the use of OPC has largely been discredited.

3. Properties
• Lime mortar is not as strong in compression as OPC mortar, but both are
sufficiently strong for construction of non-high-rise domestic properties.
• Lime mortar does not adhere as strongly to masonry as OPC. This is an
advantage with softer types of masonry, where use of cement in many
cases eventually results in cement pulling away some masonry material
when it reaches the end of its life. The mortar is a sacrificial element
which should be weaker than the bricks so it will crack before the
bricks. It is less expensive to replace cracked mortar than cracked
bricks.
• Under cracking conditions, OPC breaks, whereas lime often produces
numerous microcracks if the amount of movement is small. These
microcracks recrystallise through the action of 'free lime' effectively
self-healing the affected area.

4. Properties (conti.)
• Historic buildings are frequently constructed with relatively soft masonry units (e.g.
soft brick and many types of stone), and minor movement in such buildings is quite
common due to the nature of the foundations. This movement breaks the weakest
part of the wall, and with OPC mortar this is usually the masonry. When lime mortar
is used, the lime is the weaker element, and the mortar cracks in preference to the
masonry. This results in much less damage, and is relatively simple to repair.
• Lime mortar is more porous than cement mortars, and it wicks any dampness in
the wall to the surface where it evaporates. Thus any salt content in the water
crystallises on the lime, damaging the lime and thus saving the masonry. Cement on
the other hand evaporates water less than soft brick, so damp issues are liable to
cause salt formation and spalling on brick surfaces and consequent disintegration of
bricks. This damp evaporation ability is widely referred to as 'breathability'.
• Lime mortar should not be used below temperatures of 5 °C (41 °F) and takes longer
to set so it should be protected from freezing for three months.

5. MIX
A typical modern lime mortar mix would be 1 part lime putty to 3 parts washed, well graded, sharp sand. Other
materials have been used as aggregate instead of sand.
The theory is that the voids of empty space between the sand particles account for a 1/3 of the volume of the
sand. The lime putty when mixed at a 1 to 3 ratio, fill these voids to create a compact mortar. Analysis of mortar
samples from historic buildings typically indicates a higher ratio of around 1 part lime to 2 part aggregate/sand
was commonly used. A traditional coarse plaster mix also had horse hair added for reinforcing and control of
shrinkage, important when plastering to wooden laths and for base (or dubbing) coats onto uneven surfaces such
as stone walls where the mortar is often applied in thicker coats to compensate for the irregular surface levels.
If shrinkage and cracking of the lime mortar does occur this can be as a
result of either-
The sand being poorly graded or with a particle size that is too small
The mortar being applied too thickly (Thicker coats increase the
possibility of shrinkage, cracking and slumping)
Too much suction from the substrate
High air temperatures or direct sunlight which force dry the mortar
High water content in the lime mortar mix
Poor quality or unmatured lime putty

6. Types of Lime Mortar
It is also called natural lime mortar and should not be confused with the popular
type of mortar, Portland cement mortar.
There are two types of lime mortars:
• one type hardens when exposed to air, called non-hydraulic lime mortar
• the other one hardens when mixed with water, called hydraulic lime mortar.
There are also sub types under the hydraulic lime mortar category.

7. Non-hydraulic Lime Mortar
• Non-hydraulic lime is so named because it does not require water in order to harden. This type of
lime is basically taken from calcium carbonate in its purest forms, i.e. limestone and chalk. The
material is burned in a kiln and made to produce quicklime or calcium oxide. Quicklime becomes
calcium hydroxide once it is mixed with water. In order to reform calcium carbonate, calcium
hydroxide is made to react with carbon dioxide in the air.
• Non-hydraulic lime can be produced in two different forms, i.e. lime putty and hydrated lime.
Take note that hydrated lime is different from hydraulic lime, although the words are somewhat
similar. Hydrated lime can sometimes be hydraulic when it hardens after being mixed with water,
and non-hydraulic when it does not harden after being mixed with water. Lime putty is also
considered to be non-hydraulic and is made simply from lime and water.
• When non-hydraulic lime mortar is set in a mason unit, it takes quite a long time to harden. The
setting process may take weeks or even months or years to achieve its optimum strength. The
slow process is due to the fact that it requires carbon dioxide in the air to reform back to its
original state. Lime putty will retain its form as long as it is kept underwater and away from the
air. When it is ready for use, it can be taken out of the water and exposed to the air to harden.

8. Hydraulic Lime Mortars
• Hydraulic lime mortars are designed to harden when they
come in contact with water. In the production of a calcium
oxide, impurities in the material form aluminates and calcium
silicates that cause the material to harden when mixed with
water. The calcium oxide is then mixed with a sufficient
amount of water in the kiln to produce calcium hydroxide,
while allowing the aluminates and the calcium silicates to set.
Once the calcium hydroxide is formed along with the
aluminates and the calcium silicates, they are bagged to
prevent moisture from seeping in and hardening the mortar.
Unlike non-hydraulic lime, hydraulic lime can easily harden
after it is mixed with water.
• Hydraulic lime is graded depending on the rating and
strength of the material. Hydraulic limes are describes as
eminently hydraulic, moderately hydraulic, and feebly
hydraulic. In modern times, these grades are referred to as
NHL 5 for eminently hydraulic, NHL 3.5 for moderately
hydraulic, and NHL 2 for feebly hydraulic. NHL stands for
Natural Hydraulic Lime.

9. USES
• Lime mortar today is primarily used in the conservation of buildings originally built
using lime mortar, but may be used as an alternative to ordinary portland cement.
Portland cement has proven to be incompatible with lime mortar because it is harder,
less flexible, and impermeable. These qualities lead to premature deterioration of
soft, historic bricks so the traditionally, low temperature fired, lime mortars are
recommended for use with existing mortar of a similar type or reconstruction of
buildings using historically correct methods.
• Lime is commonly available in the United States as Type S hydrated mason's lime
(ASTM C 207). However, this lime product is intended to be added to Portland cement
to improve workability and for several other reasons. Type S lime is not reliable as a
sole cement because some manufacturers fire the lime above 1,100 °C which begins
to cause vitrification of impurities in the lime. This over-burned lime is sometimes
called dead-burned because lime fired at these temperatures loses reactivity leading
to poor or no bond strength and will not hold up to freeze-thaw weather cycles.

10. Why Use Lime Mortar
• Buildings made using slaked lime mortars are far more capable of withstanding
the vibration from traffic and the movement of the ground beneath them. Lime
mortar makes the ideal plaster for timber-frame and straw bale construction. It
will even cope well with the movement of green oak, which can be seen in so
many early Tudor houses.
• Today slaked lime mortars and mortars made with NHL (natural hydraulic lime)
are gaining ground with enlightened architects and contractors, as a better
alternative to cement mortar in new builds. It is aesthetically appealing, flexible
and far less prone to cracking, it also allows moisture to be released from walls
via the mortar bed. Garden designers are finding it superior for hard landscaping
for the same reasons
• Lime has a much lower carbon footprint as opposed to cement.

11. SPECIFICATIONS OF
EXCAVATION AND FOUNDATION

12. EXCAVATION
• EXCAVATION is the preliminary activity of the construction
project. It starts from the pits for the building foundations
and continues up to the handing over of the project.
• For small buildings, excavation is carried out manually by
means of pick axes, crow bars. spades etc. In case of large
buildings and deep excavation, mechanical earth cutting
equipment can be used like Hydraulic excavator, tractor /
trucks.
• Deep excavation or the construction of basements includes
the construction of retaining walls, excavation, the
installation of struts, the construction of foundations and
floor slabs,etc.

13. DEPTH OF EXCAVATION
• For Isolated footing the depth to be one and half
times the width of the foundation.
• For adjacent footings with clear spacing less than
twice the width (i.e.) one and half times the
length.
• 1.5m in general and 3.5 m in black cotton soils.
• For hard soils when the depth of excavation is
less than 1.5 m, the sides of the trench do not
need any external support. If the soil is loose or
the excavation is deeper, some sort of shoring is
required to support the sides from falling.

14. EXCAVATION WORKING PROCEDURE

15. PRIOR TO EXCAVATION PROCESS
Site clearance
Before excavation, the area coming under cutting
and filling shall be cleared of shrubs, vegetation,
trees and saplings of girth up to 30cm measured at
a height of one metre above ground level shall be
removed up to a distance of 50 metres outside the
periphery of the area under clearance. The trees
of girth above 30 cm shall be cut only after
permission of the Engineer-in-Charge.
Existing structures and services such as old
buildings, culverts, fencing, water supply pipe
lines, sewers, power cables, etc. within or
adjacent to the area if required to be
diverted/removed,
In case of archaeological monuments within or
adjacent to the area, the contractor shall provide
necessary fencing around such monuments as per
the directions of the Engineer-in-Charge
Preservation of Property,
Antiques and Relics
Excavating operation shall be
conducted in such a manner that
all properties, facilities, utilities
and improvements on or near the
project site, which are to remain
in place, are not damaged.
Any finds of archaeological
interest such as relics of
antiquity, coins, fossils or other
articles of value shall be
delivered to the Engineer-in-
Charge and shall be the property
of the Government.
The Contractor shall layout, and
construct one or more
permanent bench marks in some
central place before the start of
the work, from which all
important levels for the
excavations will be set.
Setting out
Blasting
Where hard rock is met with
and blasting operations are
considered necessary, the
contractor shall obtain the
approval of the Engineer-in-
Charge

16. EXCAVATION METHODS
1.FULL OPEN CUT METHOD can be further classified into:
• Slope open cut method
• Cantilever method
Slope full open cut method : excavation site is excavated with sloped sides and does not use
retaining walls or struts to obstruct excavation . In case of excavation not too deep the cost
remains cheap as there is no struts, but when excavation is deep and soil is loose and firm ,a
tremendous amount of excavated soil will be needed to backfill that turs whole the process
costly.
Cantilever method: though requiring the construction of retaining walls , does not necessitate
digging the slope and backfilling ,thus cost is low compared to full open cut method.

17. 2.BRACED EXCAVATION METHOD : Installing horizontal struts in front of retaining
walls to resist the earth pressure on the backs of walls is called braced excavation
method . The bracing system of the braced excavation method includes struts ,wales
,end braces ,corner braces ,and center posts. The function of wales is to transfer
earth pressure on the back of retaining walls on to the horizontal struts . End or
corner braces can help shorten the span of wales without increasing the number of
struts.
3.ANCHORED EXCAVATION METHODS :braced method use struts to offer lateral
support against earth pressure. Anchored methods substitute anchors for struts to
counteract the lateral earth pressure . The construction procedure as follows:
Set out first
excavation stage
Bore for
anchors
Insert tendons
into the bores
Inject grouts
Preload
anchors and
lock them
Proceed to
second stage
of excavation
Build the
foundation of
building

18. Excavation process
EXCAVATION IN ALL KINDS OF SOILS/ORDINARY/HARD ROCK
• All excavation operations manually or by mechanical means shall include excavation and ‘getting out’ the excavated materials.
In case of excavation for trenches, basements, water tanks etc. ‘getting out’ shall include throwing the excavated materials at
a distance of at least one metre or half the depth of excavation, whichever is more, clear off the edge of excavation.
• During the excavation the natural drainage of the area shall be maintained.
• In firm soils, the sides of the trenches shall be kept vertical upto a depth of 2 metres from the bottom. For greater depths, the
excavation profiles shall be widened by allowing steps of 50 cms on either side after every 2 metres from the bottom.
Alternatively, the excavation can be done so as to give slope of 1:4 (1 horizontal : 4 vertical).
• In case of excavation for foundation in trenches or over areas, the bed of excavation shall be to the correct level or slope and
consolidated by watering and ramming.
• Where hard rock is met with and blasting operations are considered necessary, the contractor shall obtain the approval of the
Engineer-in-Charge. Where blasting operations are prohibited or are not practicable, excavation in hard rock shall be done by
chiseling.
• In ordinary rock excavation shall be carried out by crowbars, pick axes or pneumatic drills and blasting operation shall not be
generally adopted.

19. MEASUREMENTS
• The length and breadth of excavation or filling shall be measured with a
steel tape correct to the nearest cm. The depth of cutting or height of
filling shall be measured, correct to 5 mm, by recording levels before the
start of the work and after the completion of the work.
• In case of open footings up to the depth of 1.5 metres, around
excavation of 30 cm. beyond the outer dimension of footing shall be
measured for centering and shuttering.
• In case of open footings/Rafts at a depth of more than 1.5 metre, around
excavation of 75 cm shall be measured for centering and shuttering.

20. EARTH WORK BY MECHANICAL MEANS
Excavators
• (i) Dipper–shovel
• (ii) Backhoe
• (Iii) Skimmer
• (iv) Dragline
• (v) Clamshell
Tractor–based Equipment
• (i) Loaders
• (ii) Tractor Shovel
• (iii) Trench Digger
• (iv) Scraper
• (v) Bulldozer and Angle-dozer
• (vi) Angledozer
Transporting Equipment
(i) Dumpers
(ii) Vibratory Roller

21. BACKFILLING
• The earth used for filling shall be free from all roots, grass, shrubs, rank vegetation, brushwood, tress,
sapling and rubbish.
• Filling with excavated earth shall be done in regular horizontal layers each not exceeding 20 cm in depth.
• All lumps and clods exceeding 8 cm in any direction shall be broken.
• Each layer shall be watered and consolidated with steel rammer or ½ tonne roller. Where specified, every
third and top must layer shall also be consolidated with power roller of minimum 8 tonnes. Wherever
depth of filling exceeds 1.5 metre vibratory power roller shall be used to consolidate the filing unless
otherwise directed by Engineer-in-charge.
• The top and sides of filling shall be neatly dressed. The contractor shall make good all subsidence and
shrinkage in earth fillings, embankments, traverses etc. during execution and till the completion of work
unless otherwise specified.

22. PLANKING AND STRUTTING
When the depth of trench in soft/loose soil exceeds 2 metres, stepping, sloping and/ or planking and
strutting of sides shall be done.
Types:
Planking and strutting shall be ‘close’ or ‘open’ depending on the nature of soil and the depth of
trench.
• Close Planking and Strutting - Close planking and strutting shall be done by completely covering the
sides of the trench generally with short upright, members called ‘poling boards’. These shall be
250x38 mm in section or as directed by the Engineer-in-Charge. The boards shall generally be placed
in position vertically in pairs. One boards on either side of cutting. These shall be kept apart by
horizontal wallings of strong wood at a maximum spacing of 1.2 metres cross strutted with ballies.
• Open Planking and Strutting - In case of open planking and strutting, the entire surface of the side
of the trench is not required to be covered. The vertical boards 250 mm wide & 38 mm thick, shall
be spaced sufficiency apart to leave unsupported strips of 50 cm average width.

23. CLOSED
PLANKING

24. Excavation for Concrete
Culverts
Neat trenches shall be excavated for
placing aprons, cut off walls and lower
portions of headwalls or wingwalls.
Excavations that are more than 1.5
metres deep and within a cofferdam in a
watercourse shall be shored, sloped
and/or stepped A maximum 1:1 slope
(angle not greater than 45 measured
from the horizontal plane) shall be
provided
Excavation for Abutments,
Approach Piers and Retaining
Walls
Excavation shall be kept to a
minimum. The limits of the excavation
shall not extend more than 1.0 meter
beyond the footprint of the footings
Excavation for River
Piers
Excavation shall be kept to the
minimum. The limits of the
excavation shall not extend more
than 1.0 meter beyond the footprint
of the footings.
Excavation for river piers shall be
isolated from the watercourse using
sheetpiling cofferdams. Sheetpiling
cofferdams shall be shored

25. REFERENCE-BHEL SCHEDULE OF RATES(2007)

26. FOUNDATIONS
• Foundation is the lowest part of a structure which provides a base for the super‐structure
and transmit the loads (live load, wing load) on the structure including the dead weight of
the structure itself to the soil below.

27. SHALLOW FOUNDATION
• A shallow foundation is a type of foundation which transfers building loads to
the earth very near the surface, rather than to a subsurface layer or a range
of depths
• According to Terzaghi, a foundation is shallow if its depth is equal to or less
than its width.
SHALLOW
FOUNDATION
SPREAD
FOOTING
COMBINED
FOOTING
RAFT OR MAT
FOOTING

28. RAFT OR MAT FOUDATION
Why it is used
• Base soil has low bearing capacity or
• Column load are so large that more than
50% of the area covered by conventional
spread footing.
• Resist unequal settlement due to
earthquake.
• Quickness of construction work.
Consist of a thick reinforced concrete slab covering the entire area of the bottom of the structure (like a
floor). This type of foundation is useful for public buildings, office buildings, school buildings, residential
quarters etc, where the ground conditions are very poor and bearing power of the soil is so low that individual
spread footing cannot be provided

29. PROCESS
Method of construction of Raft Foundation:
• The whole area is dug out to the specified depth and 30 cm more wide than the area to
be covered.
• The bed is compacted and sprinkled over with water.
• Then a layer of lime concrete or lean concrete ( 1: 8 : 16 ) is laid to a suitable thickness
to act as a bottom cover.
• After this, the reinforcement is laid. The reinforcement consists of closely spaced bars
placed at right angles to one another.
• Then the cement concrete (1 : 2 : 4 ) is laid and compacted to the required thickness.
• The concrete slab so laid is then properly cured
• When loads are excessive, thick concrete beams running under the columns can also be
constructed.

30. DEEP FOUNDATION
If the depth of a foundation is greater than its width, the foundation is known as deep
foundation.
 In deep foundation the depth to width ratio is usually greater than 4 to 5.
 Deep foundations as compare to Shallow foundations distribute the load of the super structure
vertically rather than laterally.
 Deep foundations are provided when the expected loads from superstructure cannot be
supported on shallow foundations.

31. PILE FOUNDATION
Pile foundations are the part of a structure used to carry and
transfer the load of the structure to the bearing ground located at
some depth below ground surface. A pile foundation usually consists
of a base of spread footing or grillage supported by piles at their
bottom. Piles distribute the load of structure to the soil in contact
either by friction alone or by friction combined with bearing at their
ends.
SUITABILITY :
This type of foundation is suitable under the following situations ;
When the soil is very soft and solid base is not available at a reasonable
depth to keep the bearing power within safe limits.
When the grillage and raft foundation are very expansive.
When the building is very high carrying heavy concentrated loads.
When it is necessary to construct a building along the sea shore or river
bed.

32. CLASSIFICATION

33. PRE-CAST PILE
PROCESS
• Steel form is used for the precast pile
manufacture.
• Before pore the concrete in to the form,
mobile or other kind of oil have been used.
• cement, sand ,aggregate ratio is normally
1:2:4 in pre cast pile.
• But to make the foundation stronger mix
ratio is used 1:1.5:3
• When the concrete pore in the steel form it
would be ramming by the vibrator.
Pre means before & cast means made. So precast pile refers to a pile
that has made before it is being used.

34. Pictures of Processing Precast pile
•After 3 days, pile have been covering
by the sheet.
• After 3 days of casting, steel form
would be removed.
• Then the piles would be prepare for 4
weeks curing.
•Then the piles are transported to the
site for driving
CURING

35. REFERENCES
• IS 1200 (Pt 1) Method of measurement of earth work
• IS 1200 (Pt-27) Method of measurement of earth work (by
Mechanical Appliances ) .
• IS 4988 (Part IV) Excavators .
• https://en.wikipedia.org/wiki/Lime_mortar.
• BHEL Schedule of rates(2007).