Question

Q3. A multistorey building is constructed in Al Seeb near old Muscat international airport. All the structural work like (foundations, beams, columns, slabs and walls) of the building was completed. Now they want to start the exterior work like (plastering and painting of the whole building) to complete the building.   

a. Write any four type of scaffolding suitable for the above construction.   

b. Explain briefly the four types of scaffolding mentioned in the above question with neat sketch and label its parts.

c. How to set the complete procedure of the scaffolding for the multistoried building?

d. Write any three points about the advantages of steel scaffolding over the timber scaffolding

Answer 1

Ans (a). Types of scaffolding :-

1. Single scaffolding or brick layers scaffolding

2. Double scaffolding or masons scaffolding

3. Suspended scaffolding

4. Trestle scaffolding

Ans (b)

1. Single Scaffolding (Brick layer's scaffolding):-

This consists of a single frame work of standards, ledgers, put- logs etc. , constructed parallel to the wall at a distance of about 1.20 metres. The standards are placed at 2 to 2.5 m interval. Ledgers connect the standards, and are provided at a vertical interval of 1.2 to 1.5 m. Putlogs are placed with one end on the ledgers and other end in the hole left in the wall, at an interval of 1.2 to 1.5 m. Guards, boarding and other members are placed as shown in Fig. Such a scaffolding is commonly used for bricklaying, and is also called putlog scaffolding.

2. Double or Mason's Scaffolding:-

In stone masonry, it is very difficult to provide holes in the wall to support putlogs. In that case, a more strong scaffolding is used consisting of two rows of scaffolding. Each row thus forms a separate vertical frame work. The first row is placed at 20 to 30 cm away from the wall, while the other frame work is placed at 1 m distance from the first one. Putlogs are then supported on both the frames. Rakers and cross-braces are provided to make the scaffolding more strong and stable. Such a scaffolding is also called 'independent scaffolding'.

3. Suspended scaffolding :-

This is a light weight scaffolding used for repair works such as pointing, painting etc. The working platform is suspended from roofs by means of wire ropes or chains etc. The platform can be raised or lowered at any desired level.

4.Trestle scaffolding :

Such type of scaffolding is used for painting and repair works inside the room, upto a height of 5 m. The working platform is supported on the top of movable contrivances such as tripods, ladders etc. mounted on wheels.

Ans (c) Even the tallest scaffolds need bracing, which is best performed using the super-strong triangle shape. Mounting vertical trusses join with diagonal braces to make the right triangle, but this plan just won't repeat upward when the scaffolding isn't built according to a meticulous erection method. The triangles are bent, not clean to the right-angled building's height. Consequently, the temporary frame will not dispense its load appropriately. Convincing may take place, and, since all issues are exaggerated by the number of levels, this sway factor will cause the tower to become uneven.

Mounting dimensional mistakes cause the configuration to become badly connected as it mounts past numerous floors. The workers aren't able to work safely because the platforms and building levels no longer match. At last, a poor geometrical merger brings in a seed of insecurity into the tower, a seed that will develop until it has become an at height instability mistake.

Ans (d)

A steel scaffolding is practically similar to timber scaffolding except that wooden members are replaced by steel tubes and rope lashings are replaced by steel couplets or fittings.

*Such a scaffolding can be erected and dismantled rapidly.

*It has greater strength, greater durability and higher fire resistance.

*Though its initial cost is more but its salvage value is higher. It is extensively used these days