Brick Masonry and types PDF

Preview

Summary

Explanation of brick masonry and its types , Bonds in brick masonry. Different terminologies related to brick masonry...

Description

10/31/2018

Lecture No. 6 Building Construction and Drawings, CE-213 Dr. Mohammad Ashraf, Associate Professor, Department of Civil Engineering, University of Engineering and Technology, Peshawar

Lecturer Outlines Brick Masonry Construction:  General Introduction  Terminologies  Types of Brick Masonry  Brick Masonry Bond  Tools used in Brick Masonry Construction  Quality Control in Brick Masonry Construction  Defects in Brick Masonry and Maintenance

1

10/31/2018

General Introduction  Brick masonry is the assemblage of bricks arranged in a certain pattern (bond) with mortar (cementsand, mud or lime).  Brick Masonry is one of the oldest construction method, still in use in many parts of the world including Pakistan.  According to survey made by Department of Civil Engineering, UET Peshawar, about 70% of the building stock consists of brick masonry.  Low cost, availability of materials and simplistic construction technique, are some of the advantages of brick masonry construction over the other types of construction..

Terminologies in Brick Masonry  Brick: The building block of brick masonry is called brick. Depending on quality of brick it is classified as first class, 2nd class and 3rd class.  Nominal Size: The size of brick in wall which includes mortar thickness on each size. In Pakistan the nominal size of standard brick is 9.0”x 4.5”x 3.0”  Actual Size: Actual size of standard brick in Pakistan is 8 5/8” x 4 1/8”x 2 5/8”

Brick on Edge

 Frog is a depression made on one of the bed face of brick. The frog acts as trade mark and key between adjacent courses.  Brick on bed, edge and end: Brick may be placed on bed, on edge or on end as shown in figure.

Brick on Bed

Brick on End

2

10/31/2018

Terminologies in Brick Masonry Queen Brick

 Course: A layer of brick in brick masonry wall is called course.  Stretcher Course: A course in which bricks are laid in stretcher.

Header Course Quoin Brick

Stretcher Course

 Header Course: A course in which bricks are laid in header.  Quoin Brick: The brick which is laid at the external corner of a wall is called quoin.  Queen Closer: The portion of a brick made by cutting it alo two halves.

Terminologies in Brick Masonry Head Joint

 Bed Joint: The horizontal mortar joint between any two consecutive courses.  Head Joint: The vertical joints between two adjacent bricks perpendicular to the face of wall. Bed Joint

 Body Joint: The mortar joint between two bricks in same course parallel to the course.  Brick Bat: The portion of a brick made by cutting it across its width. Brick bat may be half bat, three quarter bat or quarter bat.  King Closer: The portion of a brick made by cutting off a triangular piece between center of length and width.

Brick Bat

3

10/31/2018

Terminologies in Brick Masonry (Cont..)  Plinth Masonry: The masonry between ground level and plinth level (floor level) is called plinth masonry.  Jambs: The vertical sides of a door or window opening which support door or window.  Soffits: The bottom surface of a lintel, arch, roof is called soffit.  Sill: Bottom of the window opening is called sill. A band provided at sill level is called sill band

Plinth Masonry

Soffit Jamb Sill

Terminologies in Brick Masonry (Cont..)  Column: A column is brick masonry building is defined an isolated vertical load bearing element with aspect ratio (width to thickness ratio) less than 4.  Pillar: An isolated vertical member of considerable height to support ornaments.  Pier: An intermediate vertical portion of a perforated wall between two openings. Height of pier is equal to the height of opening.

Pilaster Spandrel

Pier

 Spandrel: The portion of a perforated wall above opening.  Pilaster: A thickened vertical member forming integral part of the wall to support loads from beams or to strengthened the wall in out-of-plane direction. Column

4

10/31/2018

Terminologies in Brick Masonry (Cont..)  Plinth Band: A continuous horizontal Reinforced Concrete (RC) or wooden member provided in a masonry wall at plinth level.  Lintel Band: A continuous horizontal Reinforced Concrete (RC) or wooden member provided in a masonry wall at lintel level.  Eve band: A continuous horizontal Reinforced Concrete (RC) or wooden member provided in a masonry wall at roof level.

Terminologies in Brick Masonry (Cont..)  Facing: The external surface of a wall  Backing: The internal surface of a wall  Hearting: The interior portion of wall between facing and backing.  Cornice: It is a projecting ornamental course near the top of a building or at the junction of a wall and ceiling.  Parapet: Wall provided at the periphery of a roof top  Coping: It is a course placed upon the exposed top of an external wall to prevent the seepage of water.

Toothing

 Toothing: The temporary wall ends where alternate stretchers project out. Projecting masonry units are called tooths.

5

10/31/2018

Types of Brick Masonry Unreinforced Masonry  A masonry without any reinforcement is called unreinforced masonry abbreviated as URM.  Appropriate to resist gravity loads.  It has limited resistance against the lateral (earthquake) loads.  It is most commonly used as it is easy to construct.

Types of Brick Masonry Reinforced Masonry  When reinforcement is provided in the masonry, it is called reinforced masonry.  It has adequate resistance against both gravity and lateral loads.  More time is required for its construction.  Hollow bricks are usually used in case of reinforced masonry  Quetta bond is a type of reinforced masonry.

6

10/31/2018

Types of Brick Masonry Confined Masonry  Wooden or reinforced confining elements are used to confined masonry from all four sides in case of confined masonry.  Columns at junctions, large opening’s sides and in long walls and, plinth, lintel and eve bands are provided to confine the masonry.  Walls are first constructed with toothing left at the junction and concrete are then poured to develop a proper bond between masonry walls and concrete elements.

Brick Masonry Bond  The arrangement of bricks in a wall to avoid continuous vertical joints is called masonry bond.  The purpose of avoiding continuity in vertical joint is to provide gravity and lateral strength to the wall by distributing loads throughout the masonry  For a good bond the length of brick shall be twice the width of brick and the lap of between bricks of successive courses shall not be less than one forth of the length of brick. For thicker bricks (>4 inch thickness) the lap shall be half of brick length.

7

10/31/2018

Brick Masonry Bond (Cont..) Bond Types:  Masonry Bonds are of many types. The first three are very common. 1.

English Bond

2.

Flemish Bond  Double Flemish Bond  Single Flemish Bond

3.

Stretcher Bond

4.

Header Bond

5.

Garden Wall Bond

6.

Raking Bond

7.

English Cross Bond

8.

Dutch Bond

9.

Monk Bond

10. Zigzag Bond 11. Brick-on-Edge Bond 12. Silverlock’s Bond

Brick Masonry Bond (Cont..) English Bond  Almost all masonry work in Pakistan is done with English bond because of its high strength.  In English Bond alternate courses of stretcher and header are used  Lap between bricks of successive courses is one forth of brick length.  Quoin brick with queen closed or three quarter bat is required at the end of wall.  In case of wall with thickness equal to even multiple of half brick length, the same course will header or stretcher on both face and back.  In case of wall with thickness equal to odd multiple of half brick length, the same course will header on face and stretcher on back and vice versa.

8

10/31/2018

Brick Masonry Bond (Cont..) Flemish Bond  Mostly used Europe

 In Flemish Bond each course consists of alternate stretcher and header bricks  Lap between bricks of successive courses is one forth of brick length.  Flemish Bond may be:  Double Flemish Bond: Wall showing Flemish bond in both facing and backing.  Single Flemish Bond: Wall showing Flemish bond in facing and English bond in backing.

Brick Masonry Bond (Cont..) Comparison B/W English and Flemish Bond S. No

English Bond

Flemish Bond

1

Alternate stretcher and header courses.

Adjacent header and stretcher in same course

2

Strongest of all bonds

Less strong for wall thickness greater than one and half brick length.

3

Rough appearanceespecially for one brick thickness

Good appearance for all thickness

4

No continuous vertical joints

Partly continuous vertical joints

5

Special care is not required

Special care is required

6

Progress of work is more

Progress of work is slow

7

Brick bats are not used, therefore costly

Brick bats are to be used, therefore economical.

9

10/31/2018

Brick Masonry Bond (Cont..) Stretcher and Header Bond  Stretcher Bond:  In Stretcher bond all bricks are laid as stretcher.  Brick bats are used at the end to break the bond.  Lap is equal to half brick length.  This bond is suitable for half brick thick walls

Stretcher Bond

 Header Bond:  All bricks are laid as header.  Three quarter bat is used at quoin to break the vertical joints  Lap is equal one forth of brick length.  This bond is used for construction of cornices, walls in well, etc.

Header Bond

Brick Masonry Bond (Cont..) Garden Wall Bond  This bond is commonly used for compound wall in which more stretchers are used to get even surface  English Garden Wall Bond  Flemish Garden Wall Bond

English Garden Wall Bond

Flemish Garden Wall Bond

10

10/31/2018

Brick Masonry Bond (Cont..) Other Bond  Raking Bond (bricks are laid at a angle)

 English Cross Bond (Similar to English bond but stretcher course starts with quoin stretcher followed by header)  Facing Bond (different bricks at facing and backing)  Dutch Bond (Similar to English bond but starts with three-quarter bat)  Monk Bond (two stretcher and one header)  Zigzag Bond (Bricks are laid in zigzag fashion)  Brick-on-Edge Bond (bricks are place on edge)  Silverlock’s Bond (stretcher course have a cavity which is bridged by header course.

Brick Masonry Bond (Cont..) Pilasters and Wall Junctions

English Bond

Flemish Bond

Tee-Junction

Pilaster

11

10/31/2018

Tools Used in Brick Masonry Construction  Trowel

 Brick Hammer Brick Hammer

 Pipe Level Trowel

 Plumb Bob

Pipe Level

 Straight Edge  Water Level  Small Measuring Tap  Masons Square

Plumb Bob

Straight Edge

Tap

 String

Water Level

Mason Square String

Quality Control in Brick Masonry  Materials:  Bricks (color, size, shape, edges, strength, texture, soaking )  Mortar (Quality of sand, Mixing, workability, time of use

 Proper Bond (No Continuous vertical Joints)  Proper construction of Corner and T-Junctions  Proper joints filling  Uniform thickness of mortar Joint  Level of courses and verticality of wall  Per day construction height (less than 1.0 m for half brick wall and 1.5 m for one brick wall)  Curing (one to two weeks depending upon weather)

12

10/31/2018

Defects in Brick Masonry and its Maintenance  Dampness

 Settlement  Frost Action  Efflorescence

Dampness

Settlement

 Corrosion of metals  Sulphates Attack in Mortar

Frost Action

Efflorescence

13...