Lecture 1 Masonry structure-Introduction, materials and priciples of design

2Mortar for concrete brick, multi-row core concrete block, single-row core concrete block and gangue concrete block: Mb20, Mb15, Mb10,Mb7.5 and Mb5; 3Mortar for two-row core or multi-row light aggregate concrete block: Mb10, Mb7.5 and Mb5; 4Mortar for rustic ashlar and rubble: M7.5, M5 and M2.5.
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SHNU CCE Zhang Chunxia
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Introduction-Reinforced masonry structure
Masonry structure can be categorized into unreinforced and reinforced masonry structures.
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Materials-Masonry: Mortar
Mortar is usually obtained by mixing sand, cement and water. For special applications, lime or a mortar plasticizer is also used. Lime is used in mortar for the following reasons: • to create a consistency and enable mortar to cling and spread • to help retain the moisture and prevent the mortar from setting Too quickly • to improve the ability of the mortar to accommodate local movement.
Βιβλιοθήκη Baidu
Double-leaf masonry
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Materials-Masonry: Bricks and Blocks
Bricks: Common
voidage15%
perforated
voidage >15%
standard 240x115x53
Ashlars work consists of regularly cut blocks with squared edges
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Samples
Brick
Big hole hollow block voidage>35% Bed face Stretcher face Header face
P-type 240x115x90
M-type 190x190x90
Processing: fired and autoclaved Material: mud sand-lime flyash concrete Blocks: Sing-row core, two-row core and multi-row core Concrete and light aggregate concrete Stone
College of Civil Engineering Shanghai Normal University
Masonry structures
Lecture 1: Introduction, Materials and Principles of Design
Ms. Zhang Chunxia
Contents
mesh-reinforced masonry composite walls columns hybrid masonry columns or walls 7 SHNU CCE Zhang Chunxia 2013/12/2
Introduction-Masonry structure
Single-leaf masonry
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Materials-Masonry: Bricks and Blocks
There are varied types of structural unit: Fired common bricks and fired perforated bricks; MU30-MU10; Autoclaved sand-lime bricks and autoclaved flyash-lime bricks: MU25-MU15; Concrete bricks an concrete perforated bricks: MU30-MU15; Concrete Block and light aggregate concrete block: MU20 MU15, MU10, MU7.5, MU5; Stone masonry: Appendix A MU100, MU80, MU60, MU50, MU40, MU30, MU20 Rubble Ashlars(fine-dressed, rustic –dressed, rubble ashlar)
Introduction Materials-brick, block and mortar Principles of design
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Introduction-Brief history
Masonry structure is a structure in which the building ‘s main load-bearing capacity comes from the wall and the column built with units and mortar, and is a general designation for structures of brick masonry structure, block masonry structure and stone masonry structure. Structural masonry has been widely used for many centuries in civil and structural works including buildings, bridges, tunnels, retaining walls, sewerage system, etc.
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SHNU CCE Zhang Chunxia
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Materials-Masonry: Mortar
Clause 3.1.3 The following stipulations shall be applied to the strength grade of mortar: 1Ordinary mortar for fired common brick, fired perforated brick, autoclaved sand-lime brick and autoclaved flyash brick: M15, M10, M7.5, M5 and M2.5; specilized masonry mortar for autoclaved sand-lime brick and autoclaved flyash brick: Ms15, Ms10, Ms7.5 and Ms5 ;
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Block
Materials-Masonry: Mortar
Mortar is the medium which binds together the individual structural units to create a continuous structural form, e.g. brickwork, stonework, etc. Mortar has a number of functions in masonry structures as follows: • binding together the individual units • distributing the pressure evenly through the individual units • infilling the joints between the units and hence increasing the resistance to moisture penetration • maintaining acoustic characteristics of a wall • maintaining the thermal characteristics of a wall.
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SHNU CCE Zhang Chunxia
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Introduction-Brief history
The extensive mechanisation and development of brick-making occurred in the mid-19th century. Before this, bricks had always been made by moulding, drying and finally firing in kilns. Modern brick-making is carried out using a continuous process in which batches of bricks are loaded, fired, cooled and removed in permanent rotation. Compared with steel and concrete structures, masonry displays excellent structural, thermal and acoustic resistance to fire and weather, and does not require regular maintenance. Sometimes, it is faster and cheaper to build certain types of buildings using only masonry.
Reinforced masonry structure is a structure in which the building ‘s main load-bearing capacity comes from the reinforced members and is a general designation for structures of mesh-reinforced masonry columns, of horizontally reinforced masonry walls, of hybrid masonry columns or walls constructed of brick masonry with reinforced concrete topping or of reinforced mortar topping, of composite walls of brick masonry with reinforced concrete structural columns and of reinforced concrete masonry shear wall.