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Civil Engineering Materials
Engr Abdul Qadeer Afridi
Department of Civil Engineering
IQRA NATIONAL UNIVERSITY PESHAWAR
BUILDING STONES
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Building Stone
• Stone: A construction material derived
from rocks in the earth’s crust and mixture
of two or more minerals.
• Mineral is a substance which is formed by
the natural inorganic process and
possesses a definite chemical composition
and molecular structure.
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Building Stones
• Stones used in most historical places
– Pyramids of Egypt
– Taj Mahal of Agra, India
– Great wall of China
– Greek and Roman structures
– Quaid’s Mausoleum in Karachi
– Shahi mosque in Lahore
– Forts at Rohtas, Lahore
– Grand Trunk Road
– Lloyd’s Barrage at Sukkur
History
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Taj Mehal ??
The Great Pyramids
??
History
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The Roman Colosseum Badshahi Musjid
Lake Vyrnwy
Dam , England
Modern Use
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Civil Engineering Uses
• Construction of residential and public buildings
• Construction of dams, weirs, harbors, bridge abutments, etc
• Face work of structures for appearance and ornamental value
• Road metal and railway ballast
• Aggregate for concrete
• Stone dust as substitute for sand
• Thin slabs for roofing, flooring and pavements
• Limestone for manufacture of lime, cement, etc
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Building Stones
• Stone as building material lost its
importance due to
– Advent of cement and steel – less bulky,
stronger and more durable
– Structural strength can not be rationally
analyzed
– Transportation difficulties
– Dressing problems
Stone Balast
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Classification of Rocks
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Classification of Rocks
Rocks
Geological Physical Chemical
Igneous
Sedimentary
Metamorphic
Stratified
Un-Stratified
Foliated
Argillaceous
Siliceous
Calcareous
Practical
Granite,
Basalts
Marble
Limestone,
Sandstone,
Slate
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Classification of Rocks
• Geological classification
– Igneous rocks (primary, un-stratified, eruptive) – cooled down molten volcanic lava (magma). Basalts and granites.
– Sedimentary rocks (aqueous, stratified) – gradually deposited disintegrated rocks. Sand stones and lime stones
– Metamorphic rocks – transformed due to great heat and pressure. Granite to gneiss, lime stone to marble, shale to slate
Igneous Rock
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Sedimentary Rocks
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Metamorphic Rocks
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Classification of Rocks
• Physical classification
– Stratified rocks – separable distinct layers.
Cleavage plane of split visible. Slate,
sandstone, lime stone
– Un-stratified rocks – no sign of strata, cannot
be easily split into slabs. Granite, basalt, trap
– Foliated rocks – having tendency to split up
only in a definite direction
Stratified Rocks
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Un-stratified Rocks
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Foliated Rocks
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Classification of Rocks
• Chemical Classification
– Siliceous rocks – containing silica SiO2 (sand)
and silicates. Granite, basalt, trap, quartzite,
gneiss, syenite, etc
– Argillaceous rocks – containing clay or
alumina Al2O3. Slate, laterite, etc
– Calcareous rocks – containing calcium
carbonate or lime. Limestone, marble,
dolomite, etc
Calcareous Rocks
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Argillaceous rocks
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Siliceous rocks
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Classification of Rocks
• Practical Classification
– Granites
– Basalts
– Marbles
– Sandstones
– Slates
– Etc, etc
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Stone Mountain, Atlanta, USA
Igneous Rocks
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Red Granite
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Vesicular Basalt
Sedimentary Rocks
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Old Red Sandstone
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Red Devonian Sandstone
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Basalt and Sandstone
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Limestone and Slate
Metamorphic Rocks
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Green Slate
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Metamorphic Rocks
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Metamorphic Rocks
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Gneiss
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Granitic Gneisses
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Granitic Gneisses
Miscellaneous Sedimentary
Material
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Glacially Transported Potpourri
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Glacially Transported Potpourri
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Chert Nodules (Flints)
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Chert Nodules (Flints)
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Chert Nodules
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Cenzoic Coral
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Stone Masonry
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Characteristics of Good
Building Stones • Appearance & color – uniform color, lighter shades
preferred, free from clay holes, bands or spots
• Structure – Not dull in appearance, crystalline homogenous close grained is good, stratification should not be visible, fine grained for carving
• Weight – heavier are compact, less porous, good for hydraulic structures
• Strength – generally compressive strength needed, igneous rock stones are stronger
• Hardness– resistance to abrasion, friction and wear. Hardness scale 1 to 10
• Toughness – Withstand impact, vibrations, moving loads
• Dressing – uniform texture and softness for fine surface finish
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Characteristics of Good
Building Stones • Porosity and Absorption – exposed surface absorbs rain
water forming acids causing crumbling action. Cyclic freezing and thawing of pore water
• Seasoning – hardening and weathering affect due to evaporation of quarry sap and formation of crystalline film. 6 to 12 months for proper seasoning
• Weathering – resistance to action of weather
• Resistance to fire – free from calcium carbonate or oxides of iron
• Durability – compact, homogenous and less absorptive is more durable
• Cost – quarrying, transportation, dressing and installation
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Moh’s Hardness Scale
• 1 Talc, scratched easily by thumb nail
• 2 Gypsum, scratched by thumb nail
• 3 Calcite, scratched not by thumb nail but by knife
• 4 Fluorite, cut by knife with difficulty
• 5 Apatite, cut by knife with difficulty more than 4
• 6 Orthoclase, cut by knife with great difficulty
• 7 Quartz, not scratched by steel, scratches glass
• 8 Topaz
• 9 Corundum
• 10 Diamond
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Moh’s Hardness
Scale
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Talc Gypsum Calcite Flourite Apatite
Orthoclase Quartz Topaz Corundum Diamond
Minerals
Quarrying of Stones
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Quarrying and Dressing
• Quarrying: An art of extracting stones from
the rock beds of different varieties used for
general building work and broken stones
for roads and concrete work, etc
• Quarry: The place from stone is obtained
by digging or blasting etc
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Quarrying Methods
• Digging or Excavating Method. Stones occurring as detached nodules may be dug using manual methods like crowbars etc
• Heating Method. Rock surface is heated for several hours resulting into unequal expansion and crushing of rock into small pieces
• Wedging Method. Layered rock is split at cleavage or seam using steel wedges and pins
• Blasting Method. Hard and compact rock is blasted out using explosives techniques comprising boring, charging, tamping and firing
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Quarrying
Tools
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Blasting Procedure
• Boring. Drilling of holes in rock using jumper, manual drilling or machine drilling using pneumatic or mechanical power
• Charging. Placing of required quantity of explosive charge in the hole at desired location. Quantity depends upon explosive strength, blasting method, number of holes, type and mass of rock – Gunpowder or Dynamite explosive (gms) = Square of length of
line of least resistance (m) / 0.008
• Tamping. Placing of priming charge, detonation cable (cordite), and sealing off the escape of gases
• Firing. detonation mechanism (electrical or non-electrical detonators) or fuse ignition
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Blasting Precautions
• Blasting should not be carried out in late evening or early morning. Blasting should be made public with sufficient time allowed to retire to safe distance
• 200 m radius danger zone should be marked with red flags
• First aid should be made available
• Proper record of number of charges prepared, fired and exploded to account for misfires
• Explosive should be handled carefully
• Detonators and explosive should not be stored and kept together
• Cartridges should be handled with rubber gloves
• Maximum of 10 bore holes should be exploded at a time and that too successively and not simultaneously
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Stone Dressing
• Pitched faced dressed – 2.5 cm edges dressed and made square
• Hammer dressed, hammer faced, quarry faced or rustic faced – dressed like a brick with 2.5 cm rough edges for use in masonry
• Rock faced and chisel drafted – chisel draft of 2.5 cm along edges
• Rough tooled – edges and corners made perfect square and true
• Punched dressed – rough tooled improved up to 2 mm
• Fine tooled – fair smooth surface for ashler masonry
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Dressed Stone Surfaces
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Dressed Stone Surfaces
Stone Care
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Deterioration of Stones
• Rain. – Physical Action. Disintegration, erosion,
transportation due to alternate wetting and drying
– Chemical Action. Decomposition, oxidation and hydration of minerals due to acids formed with rain water
• Frost. Pierces the pores, freezes, expands and creates cracks
• Wind. Abrasion due to wind carried dust
• Temperature Changes. Expansion and contraction affects on minerals of different coefficients of linear expansion
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Deterioration of Stones
• Vegetable growth. Roots of trees and
weeds in cracks and fissures
• Mutual decay
• Chemical Agents. Smokes, fumes, acids
and acid fumes from atmosphere
• Lichens. Destroy lime stones. Molluses
make series of parallel vertical holes
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Avoiding Deterioration
• Initial selection – use compact, crystalline stones instead of porous material
• Seasoning – Seasoned stones are less liable to deterioration due to frost and acids
• Size – it does matter – bigger is more durable than smaller ones
• Natural bed – placing on natural bed provides greater strength and is detrimental to rain and frost
• Surface finish – well dressed, smooth finished and polished is more durable
• Workmanship – all joints filled leaving no cavities in masonry
• External rendering – pointing or plastering to stop rain penetration
• Proper maintenance – washing, removing dirt and dust
• Application of preservatives – eliminate cause of deterioration
• Cure is better than medicine
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Natural Bed
of Stones
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Preservation of Stones
• Stones should be kept dry with blow lamp and applied coat of paraffin, linseed oil, light paint, etc
• Stones should be washed with water and steam to remove dirt and salt
• In industrial towns stones are preserved by application of solution of baryta, Ba(OH)2 to form insoluble barium sulphate
• Preservative treatment only slows down the decay but does not stop it. All have harmful side effects also
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Selection of Stones
• Cost – quarrying and cutting, dressing,
transportation charges, etc
• Fashion & Ornamental value including
color, shade, etc specially after prolong
usage
• Durability (usually overlooked and
disregarded), resistance to fire and
weathering
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Selection of Stones
• Heavy engineering works bridges, piers, abutments, break waters, docks, light houses – granite (biotite, hornblende, tourmaline)
• Buildings facing the sea – granite, fine grained sandstone
• Buildings in industrial area – granite, compact sandstone
• Arches – fine grained sandstone
• Building face work – marble, close grained sandstone
• Fire resisting structure – compact sandstone
• Road metal and aggregate for concrete – granite, basalt, quartzite
• Railway ballast – coarse grained sandstone, quartzite
• Electrical switch board – slate, marble
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Artificial Stone
• Definition - Building material made with cement, sand and natural aggregates of crushed stone for use in place of natural stone
• Properties – Made with white cement, sand and natural
aggregates of crushed stone
– Moulded into most intricate forms
– Cast into any size
– Reinforced to desired higher strength
– Desired coloring may be achieved
– Desired finish may be achieved
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Artificial Stone
• Concrete block. Cast in moulds for steps,
window sills, masonry work, etc
• Ransom stone. Soda silicate plus cement
for decorative flooring
• Victoria stone. Granite pieces immersed in
soda silicate for two months
• Bituminous stone. Provide noise, wear and
dust resistant stone surfaces
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Artificial Stone
• Imperial stone. Crushed granite plus cement, moulded, steam cured
• Artificial marble. Pre-cast or cast-in-situ. Portland gypsum cement and sand. Cast blocks treated with magnesium fluorite, washed, paper wrapped, machine emery ground, polished and finally rubbed with ball of wool moistened with alum water
• Garlic stone. Iron slag and cement mixture molded into flag stones, surface drains, etc
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Any Questions ???
Evaluation of Stones