masonry

1. masonry

2. review • Name the 4 major building systems used on a project. • structural, mechanical, enclosure and interior • Name 3 structural systems. • steel, poured concrete, precast concrete, wood • What are the 3 major parts of a building? • foundation, sub-structure, super-structure • What happens to all buildings after being completed? • they settle

3. review • What are the 2 main ways of keeping excavated sites from caving in? • benching and sheeted • With using sheeted earth retention, which is the easiest to work around? • tieback system • What may you need to do, to a building foundation if your new building foundation is deeper. • underpinning

4. review • What type of joint do you use when you must stop between two concrete pours. • construction joint with a water stop • Which type of loading deals with wind? • dynamic • When ever possible, what type of grid system should your building be laid out on. • rectangular

5. masonry • Masonry is the simplest of building techniques. • stack pieces of material atop one another to make walls • most ancient of building techniques • labour intensive • very durable • mortar was originally mud smeared into joints to give stability and to make walls weather tight. • early nineteen hundreds masonry started to loose out to other building materials such as steel for high rise buildings and poured concrete in foundations replacing the thick masonry brick walls required to support the heavy loads above. • the invention of hollow concrete block masonry helped to keep the masonry as an integral part of the building industry.

6. concrete masonry • Three types of concrete masonry units • solid bricks • large hollow units • large solid units • Concrete masonry is manufactured by vibrating a stiff concrete mixture into metal mold. • The concrete mix is immediately removed and placed on a rack to be cured in an autoclave using steam and specific pressures

7. concrete masonry • hollow concrete block is more economical per unit than brick and stone • the area of one standard concrete block unit (8”H x 16”L ) is equal to the area of 6 standard bricks • actual size of blocks are 7 7/8” H, 15 5/8” L and the width is also 3/8” smaller • the 3/8” difference is for the mortar joints • concrete block is commonly used as backup for other materials such as face brick, stucco, tile, metal sandwich panels, ……..

8. concrete masonry • the mortar that is used to adhere the block to each other is usually only placed on the external edges and not on the internal webs. • if extra structural strength is required the following can be added to the structure • horizontal masonry reinforcing • truss and ladder type ( figure 9.27 ) • horizontal rebars with low web bond type blocks (figure 9.28) • vertical rebars with the cores of the blocks filled with grout or concrete

9. brick masonry • major difference between concrete masonry and brick masonry is that most brick are made with clay and shale • three major processes in forming bricks are • soft mud • 20 to 30 percent water • pressed into rectangular molds • dry press • up to 10 percent water • used for clay that shrink excessively • stiff mud • 12 to 15 percent water • extruded through a rectangular die • passed through a vacuum to remove air pockets

10. brick masonry • most bricks will equal 3 brick courses to 1 block course ( 8” including mortar ) ( see figure 8.11 ) • bricks can be made solid, cored, hollow or frogged ( see figure 8.12 ) • specialty bricks can also be produced ( see figure 8.13 and 8.14 )

11. brick selection • types of resistance grade • SW – severe weathering • MW – moderate weathering • NW – negligible weathering • types of facing grade • FBX – high perfection • FBS – greater size variation per unit • FBA – non-uniformity in size, color and texture

12. brick laying • layout and building of brick walls start with reading drawing information, measuring and layout onto surface bricks will be laid on • basic brick laying ( see figure 8.17) • stretcher • header • soldier • rowlock • basic bond wythes ( see figure 8.18 ) • running bond • common bond • english bond • flemish bond

13. stone masonry • natural stone used on buildings is obtained by taking rock from the earth and reducing it to the required shapes and sizes for construction • Granite most commonly used in construction of all types and is classified as igneous. • multiple colours, non-porous, hard, strong, durable • can be used in contact with the ground or in locations where it is exposed to severe weathering • Limestone and sandstone is classified as sedimentary rock and are limited as to the textures they can receive • porous, limited colours, needs to dry before usage to remove quarry sap • Marble is re-crystallized form of limestone • easily to work with, multiple colours, vein pattern in appearance

14. mortar • mortar seals between units to keep water and wind out, adheres each unit together and is important to the appearance of the finished wall • four basic mortar types • M type • masonry subjected to high lateral or compressive loads • S type • masonry requiring high flexural bond strength but subjected only to normal compressive loads • N type • general use • O type • non loading bearing interior walls and partition • mortar joints vary from ¼” to ½” but the standard is for 3/8” joints.

15. mortar • mortar joints are tooled once they begin to harden to give neat appearance and compact the mortar to help prevent water penetration • outdoor joints should be concave or vee in shape ( see figure 8.24 ) • after joints have been tooled the entire surface is brushed clean and may also be washed with muriatic acid

16. masonry wall types • masonry load bearing walls can be classified in three ways: • reinforced or un-reinforced wall • composite wall, made of 2 wythes or more types of units • solid masonry wall or cavity wall