Reinforced meshes and cages: cost benefit

Examples of cost benefit analysis

Our company recommends using prefabricated reinforced products in construction. It ensures high cost effectiveness, analysis of which is presented below and proved by examples.

Example 1.	Monolith frame residential building. Height – 22 floors. Economy class. Total space – 16 thousand square meters*.

Using prefabricated frames and products saves 23.8 million roubles, which makes up 6.4% of the estimated construction cost. It is proved by the figures presented in the table.

Economic parameters	Units of measurement	Metalworking on the construction site	Supply of prefabricated frames and other products
Construction period	days	738	540
Total circulating capital	thousand roubles	34 452	—
Including the one related to: - own produced materials; - above limit construction waste; - construction period	thousand roubles	425 612 33 415	—
Cost of rebar fitters’ labour (10 people)	тыс. руб	4 356	—
Formwork (with 100 turnovers taken into account)	thousand roubles	—	1 600
Cage production cost	thousand roubles	—	17 002
Total expenses	thousand roubles	42 389	18 602
Total construction cost relative share	%	11,4	5

Example 2.	Construction of a private residential building

For reinforcement of residential building basement (10 303 m x 7 559 mm) it is recommended to use reinforcement workpieces (d=12 mm) in two levels, or meshes and cages. Comparative analysis of these variants is presented in the table. Prices are relevant as of 2009.

Option 1 (reinforcement with reinforcement workpieces, or rebars) (армирование штучной арматурой)	Option 2* (reinforcement with prefabricated meshes and cages)
Rebars – 24 204 roubles	Reinforcement meshes, cages – 21 881 roubles
Steel cutting and bending, cage assembly and welding – 12 344 roubles	Framework assembly using reinforcement meshes and cages – 6 172 roubles
Total: 36 548 roubles	Total: 28 053 roubles

* А 500 rebars are the best option to be used in reinforcement. Such rebars ensure the best cost benefit

To reduce construction costs, prefabricated cages and meshes are used for reinforcement. Variant 2 shown in the table proves high cost benefit of this option.

Basement reinforcement plans.

Reinforcement meshes and cages: cost benefit

Standardized reinforcement meshes and cages, when used in construction of various buildings, ensure high cost benefit due to:

reduction of steel spread by 10-20% due to using reinforcement products made of high efficiency advanced A500C, A500SP and B500C rolled metals instead of A400 (A-III) reinforcement products;
reduction of reinforcement anchorage and improvement of resistance to cracking and lesser change of concrete and steel construction deformation. That is because A500SP reinforcement products have good high bond to concrete;
no need to manufacture a lot of reinforcement workpieces. Usage of reinforcement meshes and cages leads to reduction of design work costs and construction labour intensity;
• reduction of manual reinforcement tying, which also leads to increase in labour productivity, and reduction of costs and construction time.

Using standardized quality-manufactured reinforcement products (reinforcement meshes and cafes, rebar cages) reduces costs, increases performance, improves constriction quality, and reduces construction time.

Reinforcement tying site on the construction field

Organization costs

Many modern construction companies have to organize reinforcement tying sites on the construction field to make welded reinforcement products. It leads to increase in construction costs due to the need to do the following:

buy equipment;
carry out site buildup (includes installation of protective structures, utilities, such as electricity supply, etc.);
make wage payments to qualified steel fitters;
get rid of waste on a regular basis.

Also, reinforcement tying site performance is worse than automatic processing lines.

Filed reinforcement lowers construction quality

Field reinforcement mesh and cage production lowers the quality of products. It happens due to failure to meet the construction parameters stated in the design, usage of low-quality reinforcement products, welding errors and faults, in other words, all those issues that are unacceptable when constructions are prefabricated.

Analysis of field-made welded construction junctions made with radiographic and ultrasonic examinations revealed that around 75% of products were defect. Also, construction companies very often use manual cage tying, which leads to considerable increase in installation of reinforcement labour efforts.

Usage of prefabricated welded products from the ecological point of view

Prefabricated welded reinforcement meshes and cages, when used in construction, do not only ensure good economic performance, but also make the construction process more eco-friendly. It is due to the fact that no reinforcement tying site is needed. Welding leads to atmospheric gas pollution and high-intensity light. Besides, such an approach lowers noise level and reduces production waste amount. All these advantages have a beneficial effect on the ecological situation and atmosphere.