lightweight concrete

1. 1. LIGHTWEIGHT CONCRETE
2. 2. DEFINITION concrete which uses lightweight aggregates May consist of lightweight aggregates are used in ordinary concrete of coarse aggregate and sand, clay, foamed slag, clinker, crushed stone, aggregates of organic and inorganic.
3. 3. Methods of preparation of lightweight concrete 2.Without providing concrete smoother 1.Preparation of porous (rough concrete) concrete 3.Providing lightweight aggregate concrete
4. 4. 1.PREPARATION OF POROUS CONCRETEa) Lightweight concrete obtained byinserting gas bubbles or air into the mixtureof plastic cement (mixed with fine sand)b) Lightweight concrete did not containstones included as porous mortar.
5. 5. Characteristics of porous concrete : 1. high thermal insulation 2. a high moisture movement 3. a high shrinkage POROUS CONCRETE
6. 6. Types of porous concrete a) type of cast in situ b) type of first cast
7. 7. Aggregates used shall comply with the following conditions: a) At least c) Stone did 95% of not diffuse aggregates through the must be via b) The stone BS 4mm the 18mm aggregate used sieve. BS sieve. shall not exceed 10% by 10 mm BS sieve.
8. 8. 2. Preparation of concrete without the smooth (rough concrete)  Lightweight concrete such as is obtained when the fine aggregate (sand) is not used and the concrete mix of cement, water and coarse aggregates. Concrete can be used for structural purposes and not to bear burden to bear a load.
9. 9. 3. Preparation of lightweight aggregate concrete• Concrete is often used in: b) the roof and walls cast in situ for use in insulation. a) before pouring the concrete block feature of lightweight aggregate concrete.
10. 10. The main purpose of the concrete requirements are: c) have low b) have a lowa) has sufficient drying shrinkage density (for strength (to avoid better insulation) cracking/rift)
11. 11. The above factors depend on: a) types of aggregates used b) the mixture c) the d) the density methods and techniques of preservation
12. 12. Characteristics ofLightweight Concrete Thermal Fire insulation insulation Durability Rain Acoustic Water penetration properties absorption
13. 13. Thermal insulationThermal insulation efficiency is defined as resistanceto heat flow either through conduction, or radiation.Lightweight concrete has a high heat insulationresistance.such as porous concrete walls 150mm to provide fourtimes better insulation than 225mm thick brick wall.
14. 14. Fire insulation• Fire prevention is associated with thermal insulation. two types of fire protection b) a non-combustible a) combustible materials - such as materials - such non-organic materials as organic such as wood stone, bricks, rocks and other.
15. 15. DurabilityIt is defined as the ability to bear the effects of environmentsuch as the effects of chemical, physical stress and mechanicaleffects. The intended effect of the chemical, including groundwater containing sulfate, air pollution and reactive liquid spills.Physical stress is the shrinkage, the stresses oftemperature, cooled, and others. If all the physical stress willcause cracks in the structure of lightweight concrete.Mechanical effect is the impact and costs are excessive. Thesituation in the steel structure unit should be protected fromrusting.
16. 16. Water absorptionAbsorption water by the concrete is high andmore than that found in solid concrete. This isbecause the lightweight concrete has holes in it.
17. 17. Penetration of rain water It is an important element to the wall
18. 18. Acoustic propertiesThe key factor is the density ofthe sound insulation material.Therefore, for soundinsulation, lightweight concretecan not show the desiredcharacteristics.
19. 19. ii) Economical ini) rapid and terms ofrelatively transportation assimple well as reductionconstruction in manpower Advantages iv) Most of lightweight concrete haveiii) Significant reduction better nailing and sawingof overall propertiesweight results in saving than heavier and strongerstructural convensional concreteframes, footing or piles
20. 20. Disadvantages i) Very sensitive with water content in the mixtures iii) Mixing time is longer than ii) Difficult to place and finish conventional because of the porosity and concrete to assure angularity of the aggregate. In proper mixing some mixes the cement mortar may separate the aggregate and float towards the surface
21. 21. Example :• ‘The Phantheon’
22. 22. Lightweight concrete specimen after adhesive tensile test
23. 23. New innovative Lightweight Foam Concrete Technology
24. 24. Lightweight Concrete (MSDS) - Spec Mix® Set Delayed Mortar