RU2203481C2 - Procedure evaluating quality of hydraulic insulation - Google Patents

Abstract

FIELD: construction industry, specifically, reconstruction and restoration of buildings. SUBSTANCE: procedure evaluating quality of hydraulic insulation includes determination of moisture absorption of material of building structure by way of measurement of relative gravimetric humidity and its comparison with rated value. Novelty of invention lies in additional establishment of water vapor permeability by measurement of diffusion rate of water vapor. In this case value of water vapor permeability is used for comparison and is established experimentally by construction of dependence of diffusion rate of water vapor on relative gravimetric humidity of sample, wet and drying to constant mass. Quality of hydraulic insulation is considered satisfactory if measured value of diffusion rate of water vapor for given relative gravimetric humidity is less than value obtained by experimental dependence. EFFECT: raised reliability of results of evaluation of quality of hydraulic insulation of building structure. 1 dwg

Description

Technical field
The invention relates to construction, in particular to the reconstruction and restoration of buildings, and can be used to assess the quality of waterproofing of building structures.

State of the art
The reliability of the operation of building structures largely depends on the quality of waterproofing works. With the complete or partial destruction of waterproofing, the foundation and brickwork of the building are moistened, the insulating properties and frost resistance, resistance to biological damage and comfort are violated. When reconstructing and restoring buildings, it becomes necessary to assess the quality of waterproofing.

 The quality of the waterproofing coating is characterized by the physicochemical properties of the material of the building structure. The unsatisfactory state of waterproofing changes the properties of the material. You can evaluate its quality by the appearance of the building structure. The walls are saturated with moisture, the solution is crumbled from the joints of the masonry, the concentration of salts increases and they crystallize on the surface of the building structure.

 The best-known method for assessing the quality of waterproofing is based on determining moisture absorption by measuring the relative weight moisture of building materials (GOST 7025-91. Ceramic and silicate bricks and stones. Methods for determining water absorption, density and frost resistance control; GOST 26584-94. Roofing and waterproofing mastics. Test Methods). Assessment of the quality of waterproofing is carried out by comparing the relative weight moisture of a building structure material with a known standard value (for example: I.A. Grachev, A.V. Petryaev, V.V. Ganchits. Experience of drainage of walls of residential buildings // Housing construction, 1995, 11 )

 The main disadvantage of this method is the low reliability of the result of assessing the quality of waterproofing, since the vapor permeability of the material of the building structure is not taken into account. Measurement of vapor permeability allows you to evaluate the removal of moisture from the building structure. Thus, the simultaneous measurement of water-absorbing properties and vapor permeability of a building construction material will improve the reliability of the results of assessing the quality of waterproofing.

SUMMARY OF THE INVENTION
The aim of the present invention is to improve the reliability of the results of assessing the quality of waterproofing of a building structure.

 This goal is achieved by the fact that according to the claimed method of assessing the quality of waterproofing, including determining the moisture absorption of a building structure material by measuring relative weight humidity and comparing it with a standard value, the vapor permeability is additionally determined according to the invention by measuring the diffusion rate of water vapor, and the standard vapor permeability value is established experimentally by obtaining the dependence of the rate of diffusion of water vapor on the relative weight humidity for wet and drying to a constant mass of the sample, and the quality of waterproofing is considered satisfactory if the measured value of the rate of diffusion of water vapor for a given relative weight humidity is less than the value obtained from the experimental dependence.

 The inventive method differs from the prototype in that to assess the quality of the waterproofing of the material of the building structure, the vapor permeability of the building material is measured and the experimental (normative) dependence of the rate of diffusion of water vapor on relative weight humidity is pre-established. This dependence is determined for the material of which the building structure consists. The quality of waterproofing is assessed by measuring the values of the rate of diffusion of water vapor at a given relative weight moisture of the material at various points of the building structure with the obtained experimental dependence. The quality of the waterproofing is considered satisfactory if the measured value of the water vapor diffusion rate for a given relative weight humidity is less than the value determined by the experimental dependence.

 These differences allow us to conclude that the claimed technical solutions meet the criterion of "novelty."

 Signs that distinguish the claimed method from the prototype are not identified in other technical solutions and, therefore, provide the claimed method with the criterion of "significant differences".

 Assessment of the quality of waterproofing according to the claimed method is as follows. The experimental dependence of vapor permeability on moisture absorption for a specific material of a building structure is first established by measuring the rate of diffusion of water vapor from relative weight humidity.

For this, a material sample, previously dried to constant mass m _о , is kept in water for 48 hours and the mass of saturated sample m is determined.

The relative weight humidity W is determined by the formula (GOST 26589-94)
W = (mm _о ) 100% / m _о .

 Then, a hole is drilled in a wet sample and a water vapor diffusion rate meter sensor is inserted into it. The diffusion rate of water vapor is fixed on the device indicator in G / min. The sample dries under normal conditions for 24 hours, and again measure the relative weight humidity and the diffusion rate of water vapor, etc. to a constant mass of the sample. Thus, an experimental dependence of the vapor permeability of the building material on moisture absorption is obtained. The drawing shows a graph of the dependence of the rate of diffusion of water vapor on relative weight moisture for clay brick of plastic pressing, showing the relationship between the incoming and evaporated moisture from the material of the building structure.

 If the obtained value of the water vapor diffusion rate for a given relative weight moisture is less than the value obtained from the experimental dependence, then the waterproofing condition is satisfactory, if it is more, it is unsatisfactory, since the moisture from the building structure evaporates quickly, and the relative weight humidity is high, this indicates that waterproofing does not protect the structure from groundwater.

 Example.

As an example, the assessment of the quality of waterproofing of a building structure material made of clay brick of plastic pressing is considered. Preliminarily establish the experimental dependence of the rate of diffusion of water vapor from relative weight humidity. The plastic molding clay brick was taken as a material sample and dried to a constant mass m _о = 5030 g, after which the brick was put into water for 48 hours and weighed m = 5680 g. Relative weight humidity was calculated by the formula
W - (mm _o ) 100% / m _o = (5680-5030) 100% / 5030 = 13%
Then, a hole is drilled in the sample and a sensor for measuring the rate of diffusion of water vapor is inserted into it. Then the sample dries under normal conditions for 24 hours, and the relative weight humidity and diffusion rate of water vapor are measured again, etc. As a result, the dependence of the diffusion rate of water vapor on the relative weight humidity for the plastic clay brick is shown, which is shown in the figure.

 To assess the quality of the waterproofing of the material of the building structure, a material sample is taken and the relative weight humidity is measured in accordance with GOST 26589-94. Then, a sensor for measuring the rate of diffusion of water vapor is inserted into the design. The obtained value of the water vapor diffusion rate at a given relative weight humidity is compared with the experimental dependence. If the measured value is less than the value of the experimental dependence, then the quality of the waterproofing is satisfactory, and vice versa.

Information confirming the possibility of carrying out the invention
The proposed method can be used in the restoration and restoration of existing buildings, especially those of historical and architectural value. Before starting the restoration, it is necessary to assess the quality of the waterproofing of the building. Using the proposed method will not only significantly increase the reliability of the result of assessing the quality of waterproofing, but also improve the quality of restoration work.

Claims (1)

 A method for assessing the quality of waterproofing, including determining the moisture absorption of a building structure material by measuring relative weight humidity and comparing it with a standard value, characterized in that they further determine vapor permeability by measuring the rate of diffusion of water vapor, using a vapor permeability value for comparison, which is established experimentally by obtaining Dependence of the rate of diffusion of water vapor on relative weight humidity for wet and dry up to a constant sample mass, and the quality of waterproofing is considered satisfactory if the measured value of the water vapor diffusion rate for a given relative weight humidity is less than the value obtained from the experimental dependence.