Masonry Dr. V.Nagarajan Brick Masonry • Brickwork is masonry produced by a bricklayer, using bricks and mortar to build up brick structures such as walls. Brickwork is also used to finish corners, door, and window openings, etc. in buildings made of other materials. • Brick Masonry is defined as systematic arrangement of bricks and bonding them together with mortar • The strength of the masonry depends on – Quality of bricks – Quality of mortar – Type of bonding Brick Masonry Terminologies • Header : A masonry unit laid flat with its longest dimension perpendicular to the face of the wall. It is generally used to tie two wythes of masonry together. • Stretcher: A masonry unit laid flat with its longest dimension parallel to the face of the wall. • Course: One of the continuous horizontal layers (or rows) of masonry that, bonded together, form the masonry structure. • – Header Course: It is a course of brickwork showing only headers on the exposed face of the wall – Stretcher Course: It is a course of brickwork showing only stretchers on the exposed face of the wall Wythe: A continuous single vertical wall of brick Brick Masonry Terminologies • Arises – The edges formed by the intersection of plane surfaces of a brick are called arises. • Frog – The depression provided in the face of a brick during its manufacturing is Courses called the frog. Frog Arises Definitions • Quoins – The external corners of a wall are called Quoins. And the bricks forming quoins are called quoin bricks. E.g quoin header or quoins stretcher. – Squint Quoin: It is a brick cut such that an angle other than right angle is formed in plan • Perpends – The imaginary vertical lines which includes vertical joints called Perpends. They should be plumb. Perpends Quoin Header Quoin Stretcher Brick Masonry Terminologies • Bed: It is the lower surface of the bricks in each course • Bed Joint: It is the horizontal layer of mortar on which bricks are laid • Lap: It is the horizontal distance between vertical joints of successive courses. • Bullnose- Rounded edges are useful for window sills, and capping on low and freestanding walls. • Cownose: A brick moulded with double bullnose on end Brick Masonry Terminologies • Brick Bat: a cut brick. A quarter bat is one-quarter the length of a stretcher. A half-bat is one-half. – – – – Three fourth brick bat Half or square brick bat One fourth brick bat Bevelled brick bat • Closer - a cut brick used to change the bond at quoins. Commonly a quarter bat. – Queens closer - a brick that has been cut over its length and is a stretcher long and a quarter-bat deep. Commonly used to bond one brick walls at right-angled quoins. – Kings closer - a brick that has been cut diagonally over its length to show a half-bat at one end and nothing at the other. – Bevelled Closer: a closer obtained by cutting a triangular portion of the brick, joining half the header and full stretcher. It is used for splayed brick work like jambs of doors and windows Bond in brick masonry • It is the arrangement of bricks in each layer to avoid the continuity of vertical joints in any two adjacent courses. • NECESSITY OF BOND Bond in brickwork is provided for the following reasons: – To break the continuity of vertical joints in consecutive courses. – To ensure longitudinal and lateral strength of the masonry work. – To distribute the load uniformly over the structural mass. – To ensure the quality of work. – To ensure systematic work – To provide good esthetics – To economize the work. • REQUIRENMENTS OF GOOD BOND IN BRICK WORK – – – – – Bricks should be uniform in size. Mortar thickness should be less than 10mm Vertical joints in alternate courses should be in a single plumb line. Header should be exactly in the middle of stretcher in two consecutive courses. Brick bats should be avoided. Back to Main page Brick Masonry :Bonds • A bond is an arrangement of layer of bricks by which no continuous vertical joints are formed. • Common types of bonds are – – – – – – Header Bond Stretcher Bond English Bond Flemish Bond Raking Bond Zig-Zag bond Brick Masonry :Bonds • Header Bond All bricks are arranged in header courses. The following are some features of header bond. – Headers alone visible in elevation. Bricks are laid with their length perpendicular to wall – Lap is half the width of bricks. This is provided by using three-fourth brick bat at quoins of alternate courses – This brick bond is used for curved surface in brick work because if stretcher is used for curved surface, it would project beyond the face of wall. Brick Masonry :Bonds • Stretcher Bond (Running Bond) – All bricks are arranged in stretcher courses – Length of brick parallel to wall – Lap is half the length of the bricks. Lap is provided by half brick bat at quoins of alternate courses – Used for partition wall and half brick thick walls Brick Masonry :English Bonds • Contains alternate courses of headers and stretchers • Vertical joints of header course comes over each other • Vertical joints of stretcher course comes over each other • Wall thickness – If wall thickness is an even number of half bricks, the same course will show either header or stretcher on both face and back. The appearance of both face and back will be the same – If wall thickness is an odd number of half bricks, the same course will show header on face and stretcher on back or show header on back and stretcher on face. • One of the strongest bonds English Bond for One Brick Thick Walls • Number of half brick bats is two • A course will show either header or stretcher on both sides of the wall. The appearance on both face and back are same • A Queen closer is placed next to quoin header in header course to the full thickness of wall. This is done to break the continuity of the vertical joints in successive courses • Queen closer is not required for stretcher courses • Each alternate header lies centrally over a stretcher • The joints in the header course should be thinner than joints in the stretcher course, as there are more joints in header course than in stretcher course English Bond 2 courses of English bond English Bond for one and half brick Thick wall • Each Course has a header and stretcher course • If wall thickness is an odd number of half bricks, the same course will show header on face and stretcher on back or show header on back and stretcher on face. Flemish Bond • Headers and Stretchers are laid alternately in each course • Every alternate course start with a quoin header • Queen closer is laid next to the quoin header in alternate course to develop face lap for creating bond • Every header is centrally supported over the stretcher below it • If Wall thickness is odd number of half bricks, more brick bat is to be used • This type of bond gives better appearance, as the headers are distributed more evenly Flemish Bond Types: Double Flemish Bond • Each course presents the same appearance in front and back faces. • It gives better appearance than English bond , but is not as strong as English bond • There should always be a quoinheader in every other course. • There should always be a queencloser next to the quoin-header, which is broken at 1-brick intervals through the whole thickness of the wall. • Each course should consist of headers and stretchers alternately. Flemish Bond Types: Single Flemish Bond • Flemish bond on face side and English bond on back side • It has the strength of English bond and appearance of Flemish bond • Minimum wall thickness : one and half brick thickness • Half brick bats are used to develop laps Comparison: English bond and Flemish Bond English Bond Flemish Bond • Strength is more for walls of thickness 1⅟2 bricks or more • Strength is more for walls of 1 brick thickness. For thicker walls strength is less • Appearance of facing is more pleasing and uniform • Alternate stretchers and headers in each course • Maintaining of correct breaking of joint is easy • Skilled and experience labor required • More mortar is used • Large number of brick bats used • Appearance of facing is not pleasing • Alternate courses of stretchers and headers • Maintaining of correct breaking of joint is difficult • Skilled labor not required. It is easy and fast to construct • Less mortar is used • Less number of brick bats used Raking bond • Herringbone bond • Diagonal bond • Zigzag bond Stone Masonry • Stonemasonry is the craft of shaping rough pieces of rock into accurate geometrical shapes, mostly simple, but some of considerable complexity, and then arranging the resulting stones, often together with mortar, to form structures. • The craft of stonemasonry (or stonecraft) has existed since the dawn of civilization – creating buildings, structures, and sculpture using stone from the earth. – used to construct many of the long-lasting, ancient monuments, artifacts, cathedrals, and cities in a wide variety of cultures. – Examples: Taj Mahal, Cusco's Incan Wall, Easter Island's statues, the Egyptian Pyramids, Tenochtitlan, Persepolis, the Parthenon, Stonehenge, and Chartres Cathedral. • Natural choice for masonry, when readily available in large quantities Stone Masonry Terminologies Stone Masonry Terminologies Stone Masonry Terminologies Stone Masonry Terminologies Classification of Stone Masonry Stone Masonry Ashlar Masonry Rubble Masonry Ashlar Fine Masonry Ashlar Rough Tooled Masonry Random Rubble Masonry Un-coursed Polygon Squared Rubble Masonry Rubble Masonry Coursed Un-coursed Coursed Ashlar Rock or Quarry Faced Masonry Ashlar Chamfered Masonry Ashlar Facing Masonry Rubble Masonry • Rubble masonry is rough, unhand building stone set in mortar, but not laid in regular courses. • It may appear as the outer surface of a wall or may fill the core of a wall which is faced with unit masonry such as brick or cut stone. • Composed of irregular pieces of stones; • mason has to choose carefully each stone so that it can fit into the available space • Stones are nor dressed. Stones from quarry directly used in masonry Random Rubble Masonry • Un coursed random rubble masonry: – – – – – – – stones are laid without forming courses roughest and cheapest type of masonry ,of varying appearance Stones of different sizes and shapes used. Before lying, all projecting corners of stones are slightly knocked off. Vertical joints are not plumbed, joints are filled and flushed. Large stones are used at corners and at jambs to increase their strength. Through stone is used for every square meter of the face area for joining faces and backing. – Suitability: Used for construction of walls of low height in case of ordinary buildings. • Coursed random rubble masonry: – – – – – Stones are laid in layers of equal height the stones are laid in somewhat level courses. Headers of one coursed height are placed at certain intervals. The stones are hammer dressed. Suitability: Used for construction of residential buildings, godowns, boundary walls etc Squared Rubble Masonry • Stones roughly squared with straight edge s and sides with hammer • Un coursed squared rubble masonry: – stones are laid without forming courses in irregular pattern – Stones of different sizes and heights, but with straight edges, and faces used • Coursed squared rubble masonry: – Stones are laid in layers of equal height – the stones are laid in level courses. – Headers of one coursed height are placed at certain intervals. Stone Masonry: Precautions Stone Masonry: Precautions Stone Masonry: Precautions Comparison of Brick and Stone Masonry Comparison of Brick and Stone Masonry