Definition of mineral binding materials.
Materials which are won and prepared out of natural rocks or as a by-product of technical processes. Serve essentiality as a compound for aggregates to produce construction materials (mortar, concrete).
Types of binding materials
- Gypsum
- Limes
- Cements
Gypsum defnition
Very soft mineral composed of calcium sulfate dihydrate. Occurs in a natural state or recovered of industrial process
Production of Binding Materials
- Rocking the Stone
- Rocks Crushing
- Rocks Transportation
- Clinker Kiln
Lime reaction
CaCO3 CaO + CO2 At 900°C
Different Kind of limes
- Air-slaked limes (Non hydraulic limes) They need CO2 for hardening , so they do not harden if they stored in water
- Hydraulic limes: They can harden in water and they are water resistant after hardening
Cement content
-Content CaO, SiO2, AlO3 and Fe2O3
Cement production
- extraction
- storing and homogenization (gravel formation)
- drying and grinding (raw mix formation)
- precipitation + homogenization and cauterisation (clinker formation)
Clinker phases
- Tricalciumsilicate C3S
- Dicalciumsilicate C2S
- Tricalciumaluminate C3A
- Tetracalciumaluminateferrite C4AFresp. C2(AF)
Hydration of cement - Main reaction products
- Calcium silicate hydrate (CSH) – Responsible for the strength of the hardened concrete
- Calcium hydroxide (Ca(OH)2) – Produces the alkaline environment
Hydration of cement - Main influences on hydration
• Water – cement value • Temperature • Kind of cements (composition, fineness) • Storage and aftertreatment
Relation Between w/c-ratio and Compression Strength of Paste Matrix and Cement Mortar
Definition of Mortar. On what is it used?
MORTAR = Mineral binding material + aggregates + water
Mortar is used to:
• To join bricks to masonry (masonry mortar)
• As lining for walls and ceilings (plasters)
• As coating of floors (screed mortar)
• As an infill material of metal ducts of prestressing strands
• As fire protection or protection against corrosion
What should and should not affect theAdditive Materials and Agents of Mortar?
They should affect:
• Workability
• Water retention
• Color
They should not aaffect:
• Hardening
• Strength
• Durability
• Corrosion protection of reinforcement
Functions of Masonry Mortar and positive efects
Function of the mortar:
- to join the bricks to masonry
- Solid bed for good transfer of forces
- Spaces between the bricks must be filled to ensure transfer of shear forces and for protection
The mortar has an positive effect on :
- Humidity
- Heat
- Sound
- Fire
How is workability determined and which are the required features?
Workability is determined by quality of freshly-mixed mortar
Required features of a mortar:
• Plastic consistency, i.e. deformability, flexibility
• High water-retention
• High resistance to segregation
Good Workability is needed to ensure filling of all joint and a good bond between bricks and mortar
Strength Development of Different Kind of Mortar (graph)
Kinds of Plasters and requirements
- Exterior plasters: Protection of wall from humidity (rain). Improvement of the sight of the building. Requirements: Weather resistance (frost, sun, rain). Vapor permeable
- Interior plasters: Regulate indoor climate. Smooth base for wall papers and coating. Sound absorption. Requirement: High porosity. High water and vapor adsorption capacity. Vapor permeable
