Preparation of dry construction mixtures based on local raw material and industrial wastes for production of artificial facing plates

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PREPARATION OF DRY CONSTRUCTION MIXTURES BASED ON LOCAL RAW MATERIAL AND INDUSTRIAL WASTES FOR PRODUCTION OF ARTIFICIAL FACING PLATES

Akhmedov Mubariz Majid oglu

Abstract

The studies were performed in this work on the development of dry construction mixtures based on local raw materials and industrial wastes to produce artificial facing plates for finishing buildings of various purposes.

Keywords: facing stones, plate, Portland cement, pigment, limestone, quartz sand, water absorption, inflammability, porosity, density, polypropylene fiber, calsium formate, plastisizer, calsium stearate.

Аннотация

ПОДГОТОВКА СУХИХ СТРОИТЕЛЬНЫХ СМЕСЕЙ НА ОСНОВЕ ЛОКАЛЬНЫХ СЫРЬЕВЫХ И ПРОМЫШЛЕННЫХ ОТХОДОВ ДЛЯ ПРОИЗВОДСТВА ИСКУССТВЕННЫХ ЛИЦОВЫХ ПЛИТ

Ахмедов Мубариз Меджид оглы

Док.хим.наук, член корр. НАНА, зав. лаб. Институт катализа и неорганической химии им. акад. М.Нагиева Национальной АН Азербайджана

Халилова Махира Идаят кызы канд.хим.наук, ст.научн.сот. Институт катализа и неорганической химии им. акад. М.Нагиева Национальной АН Азербайджана, Баку

Халилов Ясин Халаф оглы канд. хим.наук, ст.научн.сот. Институт катализа и неорганической химии им. акад. М.Нагиева Национальной АН Азербайджана

Гамидов Рахман Гусейн оглы канд. хим.наук, вед.научн.сот. Институт катализа и неорганической химии им. акад. М.Нагиева Национальной АН Азербайджана

Гаджиева Кямала Исмаил кызы, канд.хим.наук, ст.научн.сот. Институт катализа и неорганической химии им. акад. М.Нагиева Национальной АН Азербайджана

Дж.А. Джамалов научн.сот. Институт катализа и неорганической химии им. акад. М.Нагиева Национальной АН Азербайджана, Баку

В этой работе были проведены исследования по разработке сухих строительных смесей на основе местного сырья и промышленных отходов для производства искусственных облицовочных плит для отделки зданий различного назначения.

Ключевые слова: облицовочные камни, плита, портландцемент, пигмент, известняк, кварцевый песок, водопоглощение, воспламеняемость, пористость, плотность, полипропиленовое волокно, формиат кальция, пластификатор, стеарат кальция.

It is known that the development of the construction sector plays one of the major roles in ensuring the country's economic development. At present Azerbaijan forms a perfect construction industry. Many construction materials previously imported from abroad are now being produced at local enterprises. Some of them are even exported to foreign countries.

One of the key requirements of the day is to provide construction objects with quality construction materials. Despite the significant achievements in the production of cement, bricks, lubricants, ceramic plate adhesives, paint and plaster products, the production of facing stones does not meet the requirements of modern construction in terms of both design and variety. Almost most of the facing stones are still being imported. Despite the fact that Gobustan limestone deposits have a certain portion of local demand, [1], large-scale and long-term production is not promising due to the following reasons:

• raw material resources suitable for processing are either no longer available or exhausted and industrial processing of "gulbakht" stone with properties of traditional high strength, density and relatively less water absorption is almost impossible;

• recently, the range of construction works in our country has significantly increased demand for facing stones. Responses to construction demands creates a problem due to the above mentioned reasons;

• Production of "aglay" facing stones is characterized by a number of technological difficulties, a large number of dusting and handmade work, low productivity that makes the production of new type of facing stones necessary;

• physical and mechanical properties of facing stones do not meet demands for facade (water absorption, frost resistance, strength, etc.).

Thus, production of new reliable and stable artificial facing stones based on local raw materials and wastes is of both practical and theoretical importance.

This research is aimed at developing the composition and technology of new generation facing products with low volume and high exploitation and aethetic properties based on local raw materials and wastes.

Methodology of studies: GOST 10178-85. Portland cement and slag- portland cement. Technical terms. We used for researches relevant 52.5 M portland cement, fineness module of 2.5-3 Garadagh quartz sand (Lokbatan deposit), swollen perlite (GOST 10832-64), sodium abietate, redispersed polymer acrylic powder and wastes of Garadag limestone deposits (0-2 mm). According to fineness module GOST8735.88 granular composition of raw materials was determined by sieving method. To prepare dry mixture raw materials were dried in laboratory drier stoves up to 0.5% humidity, sieved and weighted on technical balance using appropriate recipe, mixed dry first in a copper plate and with water. Mixing duration was maximum 3 minutes to prevent the decay of the structure of perlite. The solution was poured into 30x35x75 mm rubber molds and consolidated. Hardening mode was performed. Physical and mechanical properties of plates were determined on AZS 480-2011 [2].

Implementation of researches

To minimize the cost price the facial stone will be prepared from two layers to improve the quality of facing layer. Based on numerous literature data and practical experience we considered the preparation of lower layer from portland cement (M52.5), limestone dust (0-0.1 mm fraction), quartz sand (0.1-1mm fraction), powder polymer styrene acrylic copolymer, swollen aluminum silicates such as swollen perlite (SiO2 - 65/75%, AhOs - 1016%, K2O<5%, Na2O<4%, Ге2Оз-0-3%, MgO-0-1%, CaO-0-2%, H2O-2-6%, 0-2mm), aluminate cement and water would be appropriate [3-6]. Apparently, in the system both mineral adhesive (portland cement) and organic connector will be used. If mineral adhesive system provides mechanical properties and longevity, in our opinion, the organic binder must provide additional strength to the condenser and ensure its elastic properties. To increase the strength polypropylene fiber (6 mm) as a modifying addition, to accelerate hardening calcium formate, to give hydrophobicity to the system calcium stearate, to reduce water-cement ratio polycarboxylate ether or plasticizer CP-3, as well as to reduce volume mass by creating microporous structure sodium abietat must be used.

The top layer will be made of portland cement (M42.5), limestone powder (0 - 0,1 mm fraction), quartz sand (0 - 0.15mm fraction), polypropylene fiber (cellulose fibers 0 - 0,1 mm), calcium formate, calcium stearate, polycarboxylate ether or plasticizer CP-3, foaming Foamister NDV (siliceous organic liquid GKJ, powder polymer (Styrene acrylic copolymer), aluminate cement, Ь2СОз, pigment and water (30- 40%of a dry matter).

Production technology of “Lifeston” (LS) facing plates includes the preparation of raw material mixtures for lower and upper layers and thermal processing by pouring to rubber molds. In both cases mixture of dry matters is prepared in mini-concrete mixer for both layers. However, it has been practically determined that the preparation time of the mixture for bottom layer should not exceed 3 minutes to prevent destruction of structure of swollen perlite. The next stage of preparing a lower layer is continued with addition of water into a concrete mixer. Upper layer is mixed with water in paint mixers. Prepared lower layer mixture is poured into rubber molds (% of the mold) and after a short (510 seconds) vibration the solution of the top layer is added. Moulded products are removed with a mold after being kept for a day at 80±5⁰C and in 80-90% humid environment and left for hardening mode [7-8]. Considering that the system is sufficiently complex to determine its composition N=2^k mathematical planning method based on full factor analysis was used [9]. Portland cement (Xi - 25-30%), limestone powder (X2 - 60-65%), water: cement ratio (X3 - 0.6-1.0) were accepted as the main analyzed factors and after 28 day hardening of the mixture its stability limit - Yi (GOST) and volume mass - Y2 (GOST) were determined. In all experiments 5% of foamed perlite was added to the mixture and the rest up to 100% mass was completed with quartz sand.

Planning matrix of the experiment and results are given below.

Table 1. Planning matrix and results

Regression equation of the experiment is defined based on the results [ 9 ].

Yi = 69,87 +7,125 Xi +4,62 X2 +5,125 X3

Y2 = 1393,7 +111,25X1 -36,25X2 - 53,75X3

As seen from the regression equations, mechanical strength is observed at the top of all the factors. The impact of amount of cement on stability limit in view of effect of factors is higher. The positive effect of high water: cement ratio which is not compliant to scientific and theoretical concepts is explained by the fact that porous perlite grain draws a large portion of water into pores and hydratation process of cement does not occur at the required rate and efficiency. As seen from the second regression equation, which shows the change in volume mass, the increase in the amount of cement leads to an increase in volume mass, high water: cement ratio leads to its reduction.

At the next stage of our experiments results of full factor analysis were taken as basis base components were determined for lower and upper layers optimized with various modified additions basing to literature data and practical experiments.

Lower layer:

1) Portland cement (M42.5) - 30%

2) Limestone powder 0-0,1 mm fraction - 48%

3) Quartz sand 0,1-1mm fraction - 10%

4) Polypropylene fiber 6 mm- 0,2%

5) Calsium formate -0,8%

6) Calsium stearate - 0,2%

7) Polycarboxylate ether or plasticizer CP-3 - 0,1 %

8) Air-entraining agent (sodium a-oleine sulfonate)- 0,2%

9) Powdery polymer Styrene acrilic copolymer - 0,5 %

10) Swollen aluminosilicates (Swollen perlite 02mm)- 5%

(SiO2 - 65/75%, ALO3 - 10-16%, K2O<5%, Na2O<4%, Fe2O3-0-3%, MgO-0-1%, CaO-0-2%, H2O-2-6%)

11) Alumina cement - 5%

12) Water:cement =1.

Upper layer:

I) Portland cement (M42.5) - 35%

1) Limestone powder 0-0,1 mm fraction - 30%

2) Quartz sand 0-0,15mm fraction -30%

3) Polypropylene fiber (or cellulose fibers) 0-0,1 mm- 0,4%

4) Calsium formate - 0,6%

5) Calsium stearate - 0,2%

6) Polycarboxylate ether or plasticizer CP-3 - 0,2 %

7) Antifoaming agent Foamister NDV (siliceous organic liquid GKJ-1) - 0,2%

8) Powder polymer (Styrene acrilic copolymer) - 2%

9) Li2CO3 - 0,5%

II) Pigment - 0,2%

12) Water:cement = 0,5.

As mentioned above, artificial facing stone "Lifestone" (LS) can be used as an equivalent to "aglay" facing stones in Azerbaijan. Table 2 shows the comparison of the properties of facing stones based on the composition and technological modes described above with the properties of traditional "aglay" facing stone [9-12].

Table 2. Comparison of properties of artificial facing stones with the properties of aglay stones

concrete chemical architectural resistance

As Table 2 shows physical and mechanical properties of facing stones are much higher than the traditional "aglay" stones and fully meet the requirements of a relevant standard. These stones are mainly made of (99%) inorganic artificial and mineral substances with traditional technologies and have several advantages listed below:

• Noninflammable;

• Designers and architects are now presented with great opportunities since these stones can be prepared in a wide range and color range;

• Organization of production does not involve large investments;

• They are made of up to 70% of waste materials;

• Technologically simple

• Cost price is not high;

• Physical-mechanical properties of the product are much higher than physical-mechanical properties of traditional "aglay" stones (Table 1);

• Porosity of lower layers of materials and relative elasticity of a stone make it an essential material in earthquakes;

• Volume mass is 1.5-2 times less than "aglay" stones that reduces load of a building, minimizes foundation costs, simplifies and accelerates the facing process, excludes the use of special metal mesh and, in general, reduces the cost price of facing works.

• The proposed material has a high heat, sound and waterproofing properties.

Thus, the new generation double-layer facing stones based on local industrial wastes and mineral and organic adhesives and special modification additions fully meets the modern construction requirements due to their physical and mechanical properties and can be widely applied in industrial and civil construction works.

References

1. Aghabeyli N.M. Construction materials and products. Baku: Nurlan, 2008.-pp.544.

2. AZS 480-2011“Facing materials and products of rocks”, Testing methods.

3. Khalilov Y.Kh., Jamalov J.A., Khalilova M.I., Abbasova N.I. Construction composition for facing plates and their production technique, Invention, № a 2016 0072 AZPatent 25.07.2016.

4. Shimshek O. Construction materials II. 3. Baski, Ankara, 2007.

5. Guner M., Sume V. Construction materials and Concrete. Ankara, 2007.

6. Popov K.N., Kaddo M.B.. Construction materials and products. M.: Nauka, p.2002.-450.

7. Bajenov Y.M. Technology of concrete. M.:Nauka, p.2003.-560.

8. Yusufov I.M. Technology of concrete and iron-concrete products. Baku: publishing house of Azerbaijan University of Architecture and Construction, 1998.- pp.630.

9. Akhnazarova S.L., Kafarov V.V. Optimization of experiment in chemistry and chemical technology. M.: Higher school, 1978.- pp.319.

10. GOST 9479-98 «Blocks from rocks for facing, architectural-construction, memorial and other products. Specifications».

11. GOST 9479-94 «Blocks from natural stone for production of facing products, Specifications ».

12. GOST 7025-91 «Walling and facing materials. Methods of determining water absorption and frost resistance».

13. GOST 30629-99 «Facing materials and products from rocks. Testing methods».

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