Research method of fibreglass resistance to exposure of aggressive medium

FIELD: construction.

SUBSTANCE: study the interaction of fibreglass with cement stone within the specified time. Previously, the fibreglass is glued on the plastic plate, put into the mould to prepare cement samples and filled with cement slurry. Plastic plate with the glued fibreglass is put in such a way that the fibreglass is in contact with the cement slurry. After solidification the cement specimens are removed from the mould and the fibre is separated from the plate. Then, the fibre is investigated by means of X-ray spectrum analysis and electron microscopy. Method allows to determine the element composition, structure of interaction products of fibre with cement stone. Besides, the resistance of fibreglass compared with the diameter of fibreglass after test with the diameter of raw fibre is evaluated.

EFFECT: invention makes it possible to compare the use of fibreglasses of various compositions as reinforcing materials.

7 dwg

 

The invention relates to methods for studying the composition and structure of substances and can be used to determine the optimal mode optical fiber to disperse the reinforcement and microkeratome concrete.

Disperse reinforcement of concrete used to increase the crack resistance of concrete. One of the perspective types of reinforcing material is fiber glass of different composition. A significant obstacle to the use of fiberglass for this purpose is a low alkali resistance of glass fiber.

Known methods of studying the stability of the glass to the effects of alkalis, for example the method described in GOST 19810-85. Glass medical. Method for determination of alkali resistance. The method consists of exposing the glass to a boiling mixture of equal volumes of a solution of sodium carbonate (Na CO) concentration of 0.5 mol/DM and sodium hydroxide (NaOH) concentration of 1 mol/DM and determining the relationship of mass loss of the glass sample after the test to the unit area of the surface of the sample.

The disadvantage of this method is the fact that it is not possible to determine the composition and structure of products of interaction of glass with alkaline components.

Also known a method of determination of alkali resistance of glass fiber described in the work of Zak, F. A., Physico-chemical properties of glass fibre�. M: Wasteheat, 1962. 224 C. the Fiber is introduced into the mortar samples-beams, and determine the change in strength of specimens under tension depending on time in comparison with the same samples without fiber.

This method also makes it impossible to determine the composition and structure of the products of the reaction between the fiber and alkali.

These methods are essentially incomplete models of the process under investigation.

Criterion alkali resistance of glass fiber in accordance with the above methods is to change the size of the glass sample or changing the diameter of an optical fiber in the alkaline solution, measured under the microscope. However, the interaction of the fiber with model cement does not take into account neither the composition of the cement, the influence of the products of the interaction of minerals of cement with water, no real balance of system components "fiberglass-cement-water".

Closest to the proposed method is described in the article Sarakinos K. A. and Zamkovoy E. N. Study of the process of leaching of mineral fibers in a cement environment. / / Science. Technology. Innovation: proceedings of all. sci. Conf. - Novosibirsk, 2012. According to the study of stability of fiberglass is produced in contact with the real component, which is one of the products of hardening of cement is calcium hydroxide. After exposure of restoreamerica calcium determine the diameter of the optical fiber. The criterion of intensity of interaction with fiberglass hardening concrete is the change in fiber diameter. This method is adopted for the prototype.

The features of the prototype, coinciding with the essential features of the claimed invention: the interaction of an optical fiber with a corrosive environment within specified time; subsequent determination of the diameter of an optical fiber; about the durability of fiberglass is judged by the change in the diameter of the parts free from reaction products of the fiber compared with the diameter of the original fiber.

The disadvantage of this method is the impossibility of determining the composition and structure of products of interaction.

The object of the invention is to provide a method of research of durability of the optical fiber to interact with the cement stone, which allows to determine the composition and structure of the products of this interaction.

The task was solved due to the fact that in the known method for studying the durability of fiberglass to aggressive environments, including the interaction of fiber with a corrosive environment within specified time and subsequent determination of the diameter of an optical fiber, to change the diameter of the parts free from reaction products of the fiber compared with the diameter of the original fiber is judged on the strength of an optical fiber according to the invention in Kutch�as aggressive media used cement stone, in this pre-fiberglass glued on a plastic plate, put it in a form for the preparation of cement samples and pour cement paste, and put in the form of a plastic plate glued with optical fiber so that the fiber was in contact with cement paste, after the necessary period of hardening cement samples extracted from the mold, separating the plastic plate glued with fiberglass and fiber from the plate, the fiber is then examined using x-ray analysis and electron microscopy, determining the elemental composition and structure of products of interaction of fibers with the cement stone.

The features of the proposed technical solution, distinctive features of the solution according to the prior art: as the aggressive medium is cement stone; pre-bonded fiberglass on plastic plate; put it in a form for the preparation of cement samples and pour cement paste; put in the form of a plastic plate glued with optical fiber so that the fiber was in contact with cement paste; after the necessary period of hardening cement samples extracted from the mold; separating the plastic plate glued with fiberglass; separate the fiber from the plate; examine the fiber through a rent�espectrales analysis and electron microscopy, determining the elemental composition and structure of products of interaction of fibers with the cement stone.

Pre-gluing fiberglass to plastic plate gives the possibility of extracting fibres from hardening of cement in any period of hardening of the samples.

The introduction of optical fiber in the cement paste at the time of molding of a cement sample and the presence of fibers in the sample during the whole period of hardening will determine the composition and structure of products of interaction of fibers with the cement stone in any period.

The proposed method is illustrated by drawings, shown in Fig.1-7.

Fig.1 shows a sample label.

Fig.2 - rasplavlennyi the sample is a cube with a liner.

Fig.3 shows the structure of the surface of the glass fibers after contact with the cement stone within 28 days.

Fig.4 - the results of x-ray elemental analysis of the raw fiber.

Fig.5 - results of x-ray elemental analysis of the raw fibers after 28 days of contact with the hardening of cement.

Fig.6 - diameter optical fiber to the experiment.

Fig.7 - the surface of the optical fiber after the interaction with the cement stone. Visible area free from tumors whose diameter can be measured.

Method research of durability of fiberglass to the effects of aggression�VNOM environment is accomplished in the following sequence.

Pre-made samples in-ear (Fig.1). For this optical fiber is glued to a plastic plate. As an aggressive environment using cement stone. Put the samples in the form for the preparation of cement samples and pour cement paste. The specimen (plate glued with optical fiber) is inserted into the form so that the fiber is in contact with cement paste on one side and another side in contact with the plastic plate. The place of attaching the fibers to the plate should be above the level of the cement paste in the form.

After hardening of the cement samples within a specified time (usually 3, 7, 14, 28 days, 3, 6, 12 months or more) are extracted from the form, splitting the samples in the plane of the plate (Fig.2). Next, separate the plastic plate glued with fiberglass and separate the fiber from the plate. Then examine the fiber under electron microscope, producing photographs of the structure (Fig.3) and specifying a parallel x-ray elemental chemical analysis of the products of interaction of the fiber with cement (Fig.4, 5) and the diameter of the fiber. The intensity of interaction between fibers is judged by the change in the diameter of the parts free from reaction products of the fiber compared with the diameter of the fiber (Fig.6, 7).

The advantage of the inventive method consists in t�m, what it allows you to monitor the changes of the diameter of the fiber and determine the composition and structure of products of interaction of the fiber with cement.

Method research of durability of fiberglass to aggressive environments, including the interaction of fiber with a corrosive environment within specified time and subsequent determination of the diameter of an optical fiber, to change the diameter of the parts free from reaction products of the fiber compared with the diameter of the original fiber is judged on the strength of an optical fiber, characterized in that as an aggressive medium is cement stone, fiberglass pre-glued on a plastic plate, put it in a form for the preparation of cement samples and pour cement paste, and put in the form of a plastic plate glued with optical fiber so that the fiber was in contact with cement paste, after the necessary period of hardening cement samples extracted from the mold, separating the plastic plate glued with fiberglass and fiber from the plate, the fiber is then examined using x-ray analysis and electron microscopy, determining the elemental composition and structure of products of interaction of fibers with the cement stone.



 

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