mworlk and w ol use tt b Defne falsewort c Compore between f

mworlk and w ol use tt b) Defne falsewort c) Compore between formwork metcriads 2 what ace s)Factors affecting mwor k tormwork ties and why we use it 6) formwort design loods

Solution

Solution:

although the marks allotted not given so i will be defining in general

1a- Formwork is a structure used as a mould before concreting to give the predefined shape according to the plan. It is generally temporary in nature.

Since concrete is a mixture oor semi - solid paste ,so it cannot be poured until it has a base. Any civil engineering structure has a specific , pre-defined , measured shape. This shape is brought about by the formwork first. Thereafter the concrete is poured to give the strength and required shape according to the framework. It takes 7-28 days for concrete to achieve about 98% of its strength thus it is very important to have a strong formwork to hold it till then.

b. Falsework is more of a generalised term given to all kinds of formworks required in construction starting from shuttering to scaffolding, centering or shoring.

c.Types of formwork materials:

1.Timber - most popular and widely used. Advantages- light weight, easy to fix and remove, economical, can be sized easily. Disadvantages- less durable than steel or aluminium, must be well seasoned, can be used 3-4 times maximum.

2.Steel- mainly used in big construction projects. Costly but high reusability with excellent finishes, does not shrink, does not absorb moisture.

3.Plywood- exceptionally manufactured for construction purposes. Light weight with less thickness as compared to timber in general.Strong and can be cut into any size

4.Aluminium- It is one of the evolving construction technology and formwork equipments. Reusable and easy to fix thus timesaving. eg- MIVAN

5.Plastics and fabrics are emerging as they are reusable and ethical from an environmental point of view.

Ans.2- Although there is no specific classification by shape, but formwork can be classified according to the structural member which it supports.

1.Beam formwork

2.Column formwork

3. Slab formwork

4.Beam- slab formwork

5.Tunnel formwork

6.wall formwork

7.footing formwork, etc.

Ans 3.-The factors affecting a good formwork are as follows:

.a.Strong enough to withstand dead and live loads.
b.Capable of retaining its shape by being efficiently propped and braced horizontally and vertically.
Joints should prevent leakage of cement paste
c.Should be capable of being removed in various parts without damaging the concrete.
d.Material used be suitable for reuse.
e.As lightweight as possible.
f.Material should not warp on exposure to weathering phenomenon or heat.

Ans4-Formwork ties connect opposite faces of WALL formwork to restrain the applied concrete pressures. They transmit loads in tension between stiff vertical and/or horizontal members associated with the main formwork.

If we don\'t use ties like jacks or anchors to hold the formwork then the expansion of concrete or its hardening will create additional pressure on the formwork and damage the setup.

Ans5.- The design loads on formwork are as follows:

Vertical loads- consist of dead loads such as formwork dead load, steel reinforcement embedded in the forms, molded fresh concrete and live loads such as the weight of workers, equipments, and tools. Weight of materials is calculated separately in the case of heavy reinforcement to specify accurate unit weight.

Lateral pressure(internal) due to vibration , pore water pressure, cement grade, admixtures, etc.

Horizontal loads like wind, concrete dumping, inclined supports should be opposed by properly designed braces and shores, jacks, etc.