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Muzaffarova Maujuda, Tashkent Institute of Railway Engineering Tashkent, Uzbekistan E-mail: [email protected]
HUMIDITY OF SAND AS BUILDING AND TECHNOLOGICAL CHARACTERISTICS OF NEW RESOURCE-SAVING TECHNOLOGY SOLUTIONS FOR FIXING SHIFTING SANDS
Abstract: The article describes the research methodology, results of experiments and discussion of the results, confirming the hypothesis of a new technological solution of fixing the moving sand to produce a significant resource-saving effect. Keywor:
Introduction
Emulsions well impregnated in dry and in wet sand, however, the preparation of emulsions due to some difficulties: to obtain a homogeneous emulsion requires intensive mixing with water resins in the presence of surface-active agents (surfactants), and heated up to 70 oC [1; 2]. To do this, special arrangements apply.
Water-soluble binders, unlike high moil emulsions and binders, are prepared and applied easily, are more involved with sand during impregnation [3; 4]. Preparation and application of commercially available agricultural and road machines. At the same time, previously studied relatively expensive water-soluble substances or their clusters as an industrial waste in Uzbekistan absent [1; 2, 4-8].
In this regard, it seems urgent to develop new improved sand dune stabilization technologies based on the use of environmentally safe materials - industrial waste, by products of local production and fficient processing methods.
Research for new technological solutions
The study was carry out based on the new substance of the basic requirements [1-5] to the binder:
the ability to be absorbed into the sand to form after impregnation coagulation type of structure, nontoxicity, manu-facturability, cost and availability.
Increased solubility dextrin and adhesive polymer KP-001 in cold water and an aqueous solution of high resistance allows their use as a binder in the preparation of the protective cover of binder sand [4].
Binding properties, high stability of the aqueous solution were the main parameters for the use of these materials as binders in order to secure the shifting sands.
1.1. Research method
Experiments carried out on the sands of the air dry and wet conditions. Humidity corresponds to the values allows the impregnation of sand and form a protective crust.
Samples protective crust resulting from the impregnation were test for compliance with criteria aggregate resistance to wind-sand flow.
Selection of the composition of the working solution for impregnation dextrin sand was study at different concentrations: 5%; 3%; and 2% (Figure 1).
Results and discussion
Elastic-viscos-plastic properties of the protective cover are key in ensuring its stability [1; 2; 4; 5]. A necessary and sufficient condition for the stability of the protective cover are two characteristics, focusing all the diversity of its properties: strength plastic the P m and the thickness of the crust h. The optimal structure correspond to the values of the Pm = (2.5-2.7) x 103 Pa, h = 5 mm. With an increase in the steepness of the slope for the smallest value of a continuous layer of plastic strength increases to the Pm = 5 103 Pa. Protective crust of dextrin solution at maximum concentration and a minimum flow provides the required thickness of the protective cover; however, it is insufficient in plasticity - fragile and brittle. Consequently, when the quality requirements for the protective cover on the plastic strength (Pm > 3.103Pa\, the specific consumption of the solution can be reduced. To this end, the modification carried out with the addition of the solution of composition gossypol resin (WAN). Solutions of sand in this concentration range and binder flow provides one of the aggregates a protective cover, therefore, the study of the new method is a second criterion of (Pm > 3 ■ 103 Pa^J. There rise up of binder concentration to 2-2.5% in the dry sand and 3-3.5% in the wet sand plastic strength increases, but further its increase in concentration leads to a reduction in plastic strength.
The optimum composition of the solution in%:
• dextrin - 2.2; NaOH - 0.4; GS - 0.7; water - 96.7
• adhesive CP-001-2; NaOH - 0.4; GS - 0.7; water -96.9.
Section 12. Technical science
Pm k 10i Pa h, mm
ia
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12
10
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y' y' f y y P' n
y y / S b2
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Figure 1. Plots of plastic strength Pm depth of impregnation h on the flow q dextrin binder solution: Pm2, Pm
P
5
, Pm3
plastic protective peel strength, respectively peel strength 2%, 3%, 5% solution of dextrin on a dry sand; Pm
, P*5 - plastic protective peel strength, respectively of 2%, 3%, 5% solution of dextrin on a wet sand; h2, h3, h5 - thickness of the of the protective cover, respectively of 2%, 3%, 5% solution of dextrin on a dry sand; h2*, h3* h* - the thickness of the protective cover, respectively of 2%, 3%, 5% solution of dextrin on a wet sand; 1 -necessary-sufficient condition for the stability of the peel strength of Pplastic the Pm ; 2 - necessary-sufficient condition for the stability of the crust thickness protective cover h.
Cork obtained with the addition of the solution in the emulsion gossypol more plastic resin, thereby increasing its wind resistance. With an equal consumption of specific thickness peel solution on wet sand 1.5-2 times the thickness of the cake obtained in the dry sand, the thickness of the cover, in both cases must exceed the allowable thickness (5mm) for the aggregated demand of stability. Therefore, under the second condition P > 3 x 103 Pa relative solution flow rate can be reduced.
Table 1 shows the formula depending on the strength and thickness of the plastic protective cover from the specific consumption of the solution obtained by the graphic interpretation of the results of experiments in Excel environment with a sufficiently high confidence level in the range of variation of 0.911-0.995.
Table 1. - Equations depending of technological settings protective cover from solutions of dextrin and polymeric adhesive KP-001
Solution of con-centr ation,% Dry sand Wet sand
Рm, Pa h, mm Рm, Pa h, mm
Protective crust from solutions of dextrin and sand
5 P5 = 0.566q - 0.060 h5 = 0.775q - 0.109 P5 = 0.294q - 0.031 h5= 0.775q - 0.509
3 P3 = 0.532q - 0.065 h3 = 1.042q - 0.090 P3 = 1.120q - 0.312 h3 = 1.368q + 0.363
2 P2= 0.854q+ 0.254 h2 = 2q P2 = 1.463q + 0.036 h2 = 3.2q - 0.08
Protective crust of the KP-001 solution of glue and sand
5 P5 = 0.678 q + 0.75 h5 = 1.261 q - 0.166 P5 = 0.809 q + 0.916 h5 = 3.071 q + 0.75
3 P3 = 0.678x + 0.25 h3 = 1.595 q - 0.083 P3 = 0.75 q + 0.5 h3 = 3.202 q + 1.416
2 P2 = 0.595 q + 0.416 h2= 1.714 q P2 = 0.666 q + 0.416 h2 = 3.428 q + 1.75
Conclusions
1. The new methods FFW using local cheap materials -CP-dextrin and 1 glue.
2. The equations depending on the strength of the plastic cover and the thickness of the specific consumption of different concentrations of the solution.
3. The possibility of using new technological solutions -consolidation of sand and glue dextrin KP-001 whereby the enlarged bank technology solutions.
4. The equations depending on the strength of the plastic cover and the thickness of the specific consumption of different concentrations of the solution.
References:
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