temporary Metal Formwork presentation.pptx

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1. Metal Formwork Prepared by: Ziad Ahmed Mokhtar ID:5753

2. Introduction Formwork is either a permanent or a temporary molds in which the concrete is casted and left until it is strong enough to withstand the loads applied on it. There are many shapes and materials for formwork including but not exclusive to timber, steel and aluminum Formwork can cost between 20% to 25% of the element’s price Today we will be focusing on steel formwork

3. Steel Formwork It is made out of pre-fabricated thin metal plates stiffened along the edges by small steel angles Steel formworks are usually used in large projects and where a large number of reuses is required Steel shuttering plates is more suitable for circular or curved structures Usually used for mass structures such as dams and bridges

4. Steel Formwork Advantages Steel has a higher strength than timber formwork It is non absorbent (waterproof) No shrinkage occurs Uniform size and surface Easier to be fixed in place using clamps and bolts and rivets Steel is more durable than wood

5. Steel Formwork Disadvantages Limited size or shape Excessive loss of heat The smooth surface produced causes problems when finishing More expensive than timber formwork Difficult to handle due to heavy weight Steel plates may corrode due to constant contact with water

6. Steel Formwork comparison Steel formwork Timber formwork Time of erection Steel forms can be installed and dismantled very quickly and easier A carpenter needs to measure, cut and assemble the formwork before concrete can be casted Cost More expensive but more economical for large projects Less expensive but economical for smaller projects Durability Can be used more than 100 times Very durable and has a long service life Can be used for 5-10 times Can be easily broken when removing timber formwork

7. Steel Formwork Formwork elements and accessories Allowable stresses change from a brand to another Examples of steel formwork elements and accessories from Doca brochure

8. Steel Formwork Examples of steel formwork Steel formwork for slabs Steel formwork for stairs

9. Steel Formwork Examples of steel formwork Steel formwork for walls Steel formwork for columns

10. Steel Formwork Causes of Failures Improper stripping and shore removal Inadequate bracing Vibration Unstable soil under mudsills, shoring not plumb Inadequate control of concrete placement Lack of attention to formwork details.