At the initial stage, in monolithic construction it is necessary to pour a concrete base. For this you need to make a frame consisting of durable and smooth boards. In this case, after the pouring and curing concrete and mortar, such a structure is dismantled and re-used for later buildings. Thus, the main parameter of sheet material is the number of cycles of use, the so-called "turnover".
This parameter depends on the type of sheet material. Today for formwork is used as a plank design, and sheet of plywood of different types. And if the first to use are impractical, plywood for formwork gives a lot of advantages.
Shuttering construction plywood require less installation time, it does not require additional alignment, there are no scars and additional joints. Plywood for formwork does not deform under the weight of the concrete mass, and the installation will need less additional support. Also plywood advantageously has high moisture resistance and resistance to some chemical elements.
Let us now consider the main types of plywood for formwork, which nowadays has gained popularity. The most popular is laminated plywood, which was specially developed for use in formwork systems. It features a special outer layer which is a film for protection against aggressive external environment. It is used in low-rise and multi-storey solid construction. It has its own classification, depending on the wood. The number of repeated cycles of use of this veneer varies from 10 to 30, this is under ideal conditions and storage on construction sites is observed very rarely. Therefore, the actual "turnover" of plywood is reduced significantly. During operation, the laminated layer of plywood is damaged, the edges are chopped off, the shield gets wet, all this leads to deformation and the unsuitability of the sheet for formwork.
Also worth noting, and the usability of the sheets of plywood during installation and raspalubki. For example, sheet quality laminated plywood 1250 mm x 2500 mm x 18 mm and weighs 35 kg. This leads to the use of special equipment for the delivery boards in high rise construction.
After reviewing all the advantages and disadvantages of laminated plywood, began production of the shuttering boards made of polymers. In practical use they turned out better wood sheet materials, and decided the possible problems we might encounter in the process of use. Plastic plywood has no adhesion to the concrete solutions, eliminating the use of grease for formwork.
For example, plastic plywood Plastiwood got the same strength characteristics, withstands high loads, with deficiencies in laminated plywood. It is water resistant, resistant to chemicals, does not deform from scratches and features a non-slip flat surface. Does not require the use of grease for formwork, and mount it with nails or screws. Weight sheet plastic plywood size 1250 mm x 2500 mm x 18 mm only 17 kg, making it easy to install, disassembly and delivery of the formwork systems.
Another striking example is the plastic Board Wonderwood, the sizes of sheets which are 250 mm x 2000 mm x 18 mm, therefore it can be conveniently used to create custom forms formwork, for construction of columns and other structures in solid construction.
Sheet materials of polymers does not require special storage conditions, if necessary, easy to cut manually or with a circular saw. When you build a formwork of plastic plywood uses the same options as the set of coupling screws and nuts for formwork, or the use of reinforcing spring clip chiros in complete with key. This material does not create a residue, as it is entirely recyclable and has a high price for disposal. And most importantly, the ability to use shields more than 50 times, even in the most difficult conditions.
The cost of plastic plywood is comparable with laminated counterparts. The use of plastic plywood in concrete construction can significantly reduce the cost and facilitate the process of construction of objects of any complexity.