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reinforcement brickwork ppt
#1

Most brickwork is built without reinforcement. Historically, mortar was of low strength, and the bonding of the masonry units provided strength to the panel. Thick walls had to be bonded through the thickness as well as along the length of the wall, and old construction textbooks show in detail the ways of bonding headers with stretchers in alternate courses to avoid any continuous vertical joints.Bonds Nevertheless, the bending strength of a panel of brickwork is limited because the bricks themselves are much weaker in tension than in compression.

Modern brickwork is laid in a mortar whose strength is matched to that of the brick units themselves. Walls are mostly laid in half-brick thickness (110mm for standard metric bricks), in stretcher bond. Engaged piers or thicker sections of walls can be joined by using headers in a normal bonding pattern, but for simplicity of laying they are often joined using metal cavity ties between the stretcher-bond leaves.



Reinforced brickwork

Entire panels of brickwork can be reinforced to increase their strength to resist wind loads, or to enable a panel of prefabricated brickwork to be handled and transported. Reinforcement can also be used locally to resist potential cracking at the corners of openings, or to restrain freestanding parapets, particularly in seismic areas, where unreinforced brickwork would be too unstable.

Hailey 2aReinforcement can also be used over openings, to form a lintel in the brickwork itself. This has the advantage of showing a clean brick profile without a separate steel lintel, and also has better fire resistance. Special provisions have to be made to support the lowest course of bricks, which are hung below the reinforcement, usually with wire loops in the perpends.

The simplest form of reinforcement for brick walls is to incorporate wire reinforcement into the bed joints. This is commonly done above and below openings, since the corners of openings create a stress concentration and they are common sites for the commencement of a crack.

There are practical difficulties in placing reinforcement in the wet mortar of a bed joint. The common form of reinforcement is a ladder of wires (from 3mm to 6mm diameter longitudinally, with thinner wires welded across them), supplied flat. The reinforcement must be totally enclosed by the mortar. Galvanised steel is likely to be satisfactory in locations of low corrosion hazard, while stainless steel is preferred in maritime or polluted environments.

Horizontal joint reinforcement will provide a slight improvement in resistance to wind loads, if the panel is supported at both ends. It is of little assistance if the panel is supported top and bottom. It does not contribute to vertical loadbearing capacity.

Vertical reinforcement cannot be incorporated into the joints of a single-leaf stretcher bond panel, because there are no continuous vertical joints. In a one-brick (230mm) wall, it would be possible to place small-diameter bars in the 10mm central joint, but they would have to be located very accurately, and placed as the wall is laid. The practical ways of incorporating vertical reinforcement involve creating continuous voids in the bond pattern, or using purpose-made bricks with holes in the right place.

Quetta BondA one-and-a-half brick wall (340mm thick) laid in Flemish bond has small continuous vertical spaces in the central thickness, normally filled with cut bricks. These can be used as cores into which vertical bars can be inserted, and grouted in after several courses have been laid. This detail has been used for heavy work such as air-raid shelters and blast walls, but walls of this thickness are seldom used in normal construction.

Bricks with purpose-made core holes are the most practical solution for accommodating vertical reinforcement. The core holes must be located in the bricks so that they will align in normal stretcher bond. They have to be large enough to allow some tolerance in laying, and also large enough to allow bars of the required diameter to be inserted, lapped where necessary, and grouted with mortar or fine-aggregate concrete.
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#2
Reinforced Brickwork

Definition. Reinforced brickwork (abbreviation R.B.) is a composite structural material consisting of load-bearing brickwork masonry into which lengths of suitable metal (normally steel) are introduced and so bonded as to render the resultant composite capable of resisting not only the compressive stresses but also the tensile and shear stresses which obtain in a structure. It follows from this definition that not only may individual structural members, such as walls, columns and simple, continuous and cantilever beams and slabs be rationally designed and constructed in reinforced brickwork, but that those bonded assemblages of such members normally designated "framed structures," may also be so designed and constructed. Conrad W. Hamann .

Brick work strengthened by introduction of mild steel flats, hoop iron, expanded mesh or bars is termed as reinforced brick masonry. This reinforced brick masonry is capable of resisting both compressive as well as tensile and shear stress. On account of its ability to resist lateral forces, reinforced brick masonry is extensively used in seismic areas. It is essential to use first class bricks (having crushing strength of 140 kg/sq. cm or more) and rich and dense cement mortar in the reinforced brick work. The reinforcement should be effectively bedded and surrounded with mortar cover of 15 to 25 cm. This is necessary to protect the reinforcement against corrosion.
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#3
am Mohamed i would like to get details on reinforcement brickwork ppt ..My friend Justin said reinforcement brickwork ppt will be available here and now i am living at .. and i last studied in the college/school .. and now am doing ..i need help on ..etc
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