Types of formworks found in construction

Generally, steel or concrete is used in formwork to build part of the permanent structure. Temporary formwork can be struck and recycled from any inexpensive and easily worked material, timber, steel and GRC/GRP.

The formwork that should be utilized under the water, should abide by the following conditions :

a. Support the concrete in its designed profile during the plastic phase
b. Properly affixed into position.
c. Cover the concrete from scour, washout and abrasion till unless it gets solidified.
d. Endure mistakes in development level or alignment of adjoining work
e. Ability to resist the static and dynamic loading caused by concrete, tides, waves and currents.

It is designed in the context of the permanent works and be abandoned in situ or as temporary works either to be abandoned in situ or smitten and recycled.

The following types of formworks are mostly found :-

Ceiling Formwork: Ceiling formwork belongs to the type of formwork commonly found in structures/buildings.

The formwork sheeting comprises of sheeting boards or prefabricated sheeting panels. The formwork sheeting is located on squared timber formwork bearers to be provided on main bearers capturing the forces to round timber columns. With smaller rooms, the main bearer along with two columns develops a trestle. Diagonal board bracings are arranged to manage horizontally acting forces. The round timber columns are arranged on double wedges which function as stripping aid and correction device.

Beam Formwork: Beam formwork contains prefabricated formwork sheeting parts (sheeting bottom and side sheeting panels). Such individual parts are erected on the basis of the beam dimensions stated in the project. For prefabrication of the formwork sheeting parts, a special preparation table should be created on site.

Column Formwork: Same as beam formworks, the sheeting of column formworks is prefabricated based on the column dimensions from sheeting boards attached with cover straps.

The sheeting panels are arranged in a foot rim which is secured in the soil with steel bolts.

The foot rim consists of double-nailed boards. The foot rim must be exactly measured-in because it is decisive for the exact location of the column. It has the same functions as the thrust-board for foundation or beam formwork.

When the sheeting panels are implanted in the foot rim, vertical arch timbers are arranged to undertake the forces from the cover straps of the formwork sheeting.

Around the arch timbers, that contains the function of walers, column clamps of flat steel are braced with wedges or a rim of boards is provided same as the foot rim. Supplementary formwork tying with tie wires or steel screws is not required.

The distances of the clamps are mentioned in the formwork project. Generally, they are roughly 700 mm.

The column in the formwork is laterally fastened by diagonal board braces.



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Published By
Rajib Dey
www.constructioncost.co
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Some useful tips to work out the costs of concrete

While going to estimate the cost of new concrete, different types of variables should be taken into consideration which range from surface prep, formwork, reinforcing materials, and finish work, as well as the cost of the ready-mix concrete.

It will compute the total price of the job. Costs for certain items will differ from location to location or from site to site, but a rough estimate can be obtained with some averaged amounts.

Cost Per Yard of Ready-Mix Concrete: The most vital item should be the price of concrete, whether ready-mix concrete or other concrete material is applied. As soon as the project specifications and job location are defined, get quotes from local ready-mix concrete suppliers.

Concrete pricing is generally quoted per cubic yard or cubic meter (metre). For an average estimating number, it is recommended to apply $77 per cubic yard.

Cost of Concrete Sub-Grade Work: When the concrete is placed over soil, it is required to grade or arrange the surface for the concrete. Pricing for this can contain expenses associated with grading, compacting soil, excavating, trenching, and other components.

As a perfect average, one can apply $65 per hour of work to set up the surface, provided that the surface is in excess of 75 percent leveled and no special work is required to set up the site.

Costs for Extra Sub-Grade or Site Work: When the surface is not leveled, it is required to include expenses for more site work, like excavating and filling with proper material or eliminating a soft spot on the terrain to prepare it for bearing structural loads.

Based on the distance from where the sand or any other suitable fill material will be arranged, it could include over $10 per cubic yard or meter to your estimate. The cost might be incurred for setting up polyurethane plastic or vapor barrier prior to set the concrete.

Cost of Concrete Formwork: Building concrete forms generally demonstrate a vital part of the total cost of concrete work, as it is one of the most labor-intensive features of the job. It is necessary to recognize the type of formwork to be applied, method of installation, and whether you will purchase or rent the form materials. Other related costs may involve a crane or other equipment applied to move the form materials, form release product, re-using form materials, and the cost to repair forms after different applications.

Usually, the cost of the formwork is $1.10 per square foot of the concrete area. This estimate is prepared for a square or rectangular area. The cost of formwork is increased for rounded or contoured concrete.

Cost to Finish Concrete: Concrete prices mainly differ on the basis of the type of finishing provided in the design. Concrete gets finished in various ways like smooth surface, exposed aggregate surface, or stamped concrete finish. Some surfaces need only a strike-off and screed to suitable contour and elevation, while for others surfaces, a broomed, floated, or troweled finish should be provided. To work out finishing in your concrete pricing analysis, you can include $0.75 per square foot or perhaps more, based on the complication of the specified finish. The cost of any curing compound or testing services should also be taken into consideration.

Cost of Concrete Reinforcement: Most concrete comprises of some type of reinforcement, like rebar, wire mesh, plastic mesh, or fiber which should be added to the concrete mix to raise the strength and crack-resistance. Standard reinforcing materials can include roughly $0.18 cents per square foot. This number is higher for large-diameter rebar or other special reinforcement.



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Published By
Rajib Dey
www.constructioncost.co
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