BRICK MASONRY & ASSOCIATED TERMS BRICK MASONRY : An assemblage of bricks properly bounded together in mortar is called Brick Masonry. The Brick work used may be 230 mm thick burnt clay bricks in Cement : Sand Mortar (1:6) , For half brick thick walls the mortar used (1:4) . The bricks having minimum compressive strength of 75 kg./sq. c.m. Technical Terms Used In Brick Masonry . BRICK : An artificial masonry unit in the form of a rectangular block of prepared clay is called a brick . They are manufactured by moulding brick earth in rectangular blocks of uniform size & shape & then by drying or burning these blocks in a suitable clamp or kiln. Bricks are burnt to provide them strength & durability . The standard size of modular bricks is kept as 190mm*90mm*90mm. Their nominal size is considered as 200mm*100mm*100mm because it includes the thickness of one mortar joint on each side of the brick .The number of such bricks required for one cubic meter of brick masonry is taken as 500. BRICK TILE : An artificial masonry unit in the form of a rectangular block of prepared clay having thickness less than that of a brick is known as brick tile . The standard size of a brick tile is kept as 190mm*90mm*30mm and their nominal size is considered as 200mm*100mm*40mm. ARRISES: The edges formed by the intersection of plane surfaces of a brick are known as arrises. These are straight & sharp in case of a good quality bricks. FROG : The depression provided in the face of a brick during its manufacturing is called the frog. The size of frog in a brick is 100mm*40mm*10 to 20mm deep. A hand moulded brick has one frog a pressed brick has two frogs, where as a wire cut brick has no frog. BRICK ON BED : The position of brick when laid with its frog upward in the horizontal plane is termed as brick on bed. All the bricks unless otherwise specified are laid on their bed in all types of brickwork. BRICK ON SIDE : The position of a brick when laid on its stretcher face with frog in the vertical plane is known as brick on side. The bricks in this position are generally laid in plinth courses copings,sills etc. BRICK ON END : The position of a brick when laid on its header face with frog in the vertical plane is called brick on end. The bricks in this position are laid along the edges of brick or concrete . aprons or along pavement of roads. COURSE : Each horizontal layer of bricks laid in mortar in any brickwork is called a course. STRETCHER & STRETCHING COURSE : A Brick when laid in brickwork with its side surface or length in elevation is called a stretcher and a course in which all the bricks are laid as stretchers is called a stretching course or stretcher course. It provides longitudinal strength to the wall. HEADER & HEADING COURSE : : A Brick when laid in brickwork with its end surface or width in elevation is called a header and a course in which all the bricks are laid as headers is known as heading course or header course. It provides transverse strength to the wall. QUOINS : The external corners of walls are called quoins. BED JOINTS : The horizontal mortar joints between any two consecutive courses of brickwork are known as bed joints. These joints should be of uniform specified thickness. QUOIN BRICK : The brick which forms the external corner or a wall is known as quoin brick . A quoin brick has its one edge one end exposed to the atmosphere . If the quoin brick is laid as a header it is called a quoin header & if the quoin brick is laid as a stretcher then it is known as the quoin stretcher. CROSS JOINTS : The joints other than bed joints normal to the face of the wall are called cross joints. These joints should not extend to the full height of brickwork of a wall or pillar. PERPENDS: The vertical joints between bricks either in longitudinal or cross directions are termed as perpends . The of the alternate courses should be in the same vertical line. BOND : The arrangement of bricks or stones in each layer so as to avoid continuity of vertical joints in any two adjacent courses both on the face & inside of a masonry structure is called bond. This is done by overlapping bricks or stones in the successive courses longitudinally as well as transversely. NECESSITY OF PROVIDING BOND 1. To break the continuity of the vertical joints in the successive courses both in the length & thickness of a masonry structure. 2. To ensure longitudinal & lateral strength of the structure. 3. To enable the structure to act as a bounded mass to distribute the load uniformly to its foundation. 4. To provide pleasing appearance by laying bricks or stones symmetrically. 5. To do masonry work quickly by engaging more masons on the job at a time. TYPE OF BOND USED IN BRICKWORK ENGLISH BOND : The bond having headers & stretchers laid in alternate courses is called English bond. In this bond a queen closer is placed after every quoin header in the header course to break the continuity of vertical joints . This bond is considered as the strongest bond & does not require any special attention in its formation. This bond is also known as old english bond SALIENT FEATURES OF ENGLISH BOND 1. Header & stretcher are laid in alternate courses. 2. A queen closer is placed after every quoin header in the heading course when the thickness of wall is 200mm or above. The length of queen closer is usually kept equal to the thickness of wall. 3. The same course will show headers or stretchers on face & back if the thickness of wall is an even multiple of half brick. 4. The same course will show headers on the face & stretcher on the back & vice versa , if the thickness of wall is an odd multiple of half brick. 5. Each alternate header in the heading course lies centrally over every stretcher of the underlying stretching course. 6. Continuous vertical joints don’t occur on the face as well as on inside of the structure. 7. The inner filling is done in headers in the walls having thickness 400mm or above. TOOLS USED IN BRICK MASONRY TROWEL: It is available in various sizes ranging from 50mm to 300mm in length. It is used for lifting & spreading mortar for cutting of bricks & construction of joints. BRICK HAMMER: One end of this hammer is square & other end is sharp edged. It is used for cutting bricks to different shapes & sizes, brick paving , striking nails etc. LINE & PINS: This comprises of a 10m or more long cord forming a line provided with two metallic pins on either ends. This is stretched between quoins of the wall for maintaining the correct alignment of the courses. SPIRIT LEVEL: This tool is used alongwith the straight edge for checking the level of floors, roofs. STRAIGHT EDGE: This tool is used for checking the alignments of faces of brickwork of a wall. PLUMB RULE & BOB: It is in the form of a smooth wooden piece of 2m length , 100mm width & 10mm thickness , having its long edges parallel to each other. A plumb bob hangs from top of the wooden piece. MASON’s SQUARE : This is an exactly right angle piece made of steel or wooden section. It is used for taking & checking small measurements while providing openings for doors & windows in brickwork.