Masonry Construction
Third Lecture
Materials in Masonry Construction
March 2013
1
Reference codes:
Decreto Ministeriale 14 gennaio 2008: Norme Tecniche per le Costruzioni – NTC2008 Circolare 617-09: Istruzioni per l’applicazione delle “Norme tecniche per le costruzioni” di cui al D.M. 14 gennaio 2008
EN 1996 - Eurocodice 6 EN 1996
Parti delle NTC 2008 relativi alle costruzioni in muratura: Capitolo 4 – Costruzioni civili e industriali Sezione 4.5 – Costruzioni di muratura
Capitolo 7 – Progettazione per azioni sismiche Sezione 7.8 – Costruzioni di muratura
Capitolo 8 – Costruzioni esistenti Sezione 8.7– Valutazione e progettazione in presenza di azioni sismiche Paragrafo 8.7.1 Costruzioni in muratura
Capitolo 11 – Materiali e prodotti per uso strutturale Sezione 11.10 – Muratura portante
What is masonry? Masonry is the assemblage of units properly bonded with mortar .
Basic Components of Masonry:
units mortar grout accessory materials
Types of Bricks The quality and characteristics of masonry products are directly and exclusively determined by the raw materials and methods of manufacture used in their production. A basic introduction to this aspect of masonry will aid in understanding the finished products and how they may best be used in specific design applications.
CONCRETE MASONRY Clay bricks
Concrete Masonry Discovery of Portland cement cause the development of modular concrete masonry. The first production were heavy, unwieldy and poorly adaptable units but later inventions in molding of cement ingredients into large blocks produce a bright new material. Concrete masonry today is made from a relatively dry mix of cementitious materials, aggregates, water, and occasionally special admixtures.
Concrete Masonry Lecablocco is a small component of Leca concrete that is used different elemnts of masonry construction. . LECA stands for Lightweight Expanded Clay Aggregate. It is clay fired at a fairly high temperature. Leca is an inert granular lightweight, insulating, resistant.
Clay Bricks Clay is produced by suitable blend of clay and water. Clay is the final product of the chemical alteration over long periods of time of the less stable minerals in rock. Clays are basically compounds of silica and alumina with varying amounts of metallic oxides and other minor ingredients and impurities.
Clay Bricks Design, workmanship and material are the important elements of proficiency in masonry construction and also, quality and characteristics of raw material and methods of production. light color bricks (salmons) indicate low temperature in burning (under burning) which cause high porosity and absorption but low strength and durability and resistance to abrasion And dark color bricks (clinker) are the results of over burning and they have high compressive strength and abrasion resistance and resistance to freezing and thawing and reduction in absorption. Clays may be calcareous or non- calcareous which both of them are hydrous aluminum silicates. around 15% calcium carbonate in calcareous clays cause yellow color brick during firing. The oxide inside the non-calcareous clay, from 2to 25%, produce a buff to a pink o red color brick.
Manufacturing of Clay bricks
Forming
Drying
Burning
Drawing and Storage
Shapes of the Bricks solid solid with frog Perforated hollow cellular
Shapes of the bricks
Mortar Mortar is the medium which binds together the individual structural units to create a continuous structural form e.g. brickwork, stonework etc. Mortar serves a number of functions in masonry construction: distribute the pressures evenly throughout the individual units bind together the individual units infill the joints between the units and hence increase the resistance to moisture penetration
Mortar Present day mortars are specifically manufactured to suit the type of construction involved. In most cases they are mixtures of :
Sand Cement lime Water
Properties of mortars