Building external wall thermal insulation system damage condition monitoring method and monitoring device

Abstract

The invention discloses a building external wall thermal insulation system damage condition monitoring method and device.The method comprises the steps that firstly, an external wall sample piece is connected with a monitoring device, the external wall sample piece is placed in a climate simulation box to be monitored, and the monitoring device can monitor the strain value of the sample external wall piece; according to the method, the strain value of the outer wall is monitored, the risk early warning strain value is calculated according to the strain value of the outer wall during cracking, and the outer wall cracking is early warned by comparing the monitored strain value with the risk early warning strain value, so that the cracking risk is predicted in advance and repair is performed in time, and damage caused by damage of the outer wall is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of exterior wall insulation systems, and in particular to a method and a device for monitoring damage of an exterior wall insulation system of a building. Background Art

[0002] In the field of construction, cracking and damage of building exterior walls has always been a difficult problem to solve. After a long period of wind and sun exposure, the building exterior walls are very likely to show damage phenomena such as bulging, wrinkling, mildew, and falling off. The insulation system of the building exterior wall is generally composed of an insulation layer, a waterproof layer, a protective layer, and a fixing material. Studies have shown that the damage of the exterior wall insulation system is closely related to the water vapor in the environment. When the moisture content in the building exterior wall insulation system is high, the vapor pressure will cause the layers in the insulation system to expand when the water vapor evaporates. However, due to the different materials of each layer, the expansion coefficients of each layer are different. At the same time, when the moisture content is high, the expansion coefficients between the layers of the insulation system are different. The adhesion and shear strength will decay, causing the insulation system to be damaged by bulging, wrinkling, mildew, and falling off, which not only affects the appearance of the building, but the falling of the building's exterior wall insulation system can easily injure pedestrians and threaten the personal safety of residents. At present, it is still impossible to monitor and warn of the damage of the building's exterior wall insulation system at home and abroad. It can only be discovered and handled when the exterior wall insulation system is damaged. Therefore, there is an urgent need for a device and method that can monitor the damage of the exterior wall insulation system, give early warning to the exterior wall insulation system and deal with and repair it in time, thereby improving the safety, reliability and durability of the building's exterior wall insulation system. Summary of the invention

[0003] The purpose of the present invention is to provide a method and a device for monitoring the damage of a building exterior wall insulation system in view of the above-mentioned deficiencies in the prior art.

[0004] To solve the above problems, the technical solution adopted by the present invention is:

[0005] A method for monitoring damage of a building exterior wall insulation system comprises the following steps:

[0006] S1. Make an exterior wall sample, connect the monitoring device to the exterior wall sample, put the exterior wall sample into a climate simulation box, adjust the climate simulation box to simulate different environments, repeat n times under the same conditions, and the monitoring device can monitor the ultimate strain value when the exterior wall sample is damaged, and obtain the ultimate strain value ε1~ε2 when the exterior wall sample is cracked. n ;

[0007] S2, according to the obtained limit strain value ε1~ε n Calculate the average ultimate strain value when the exterior wall is damaged Then calculate based on the average ultimate strain value

[0008] S3, when , then remove the average limit strain value ε of this group of data avg Recalculate; when two or more groups of limit strain values ​​ε i >20%×ε avg When the limit strain value ε of group 1 or below is i >20%×ε avg When the average limit strain value ε is calculated avg ;

[0009] S4. Calculate the risk warning strain value ε°=90%×ε avg ,When the monitored strain value is ≥ε°, there is a risk of damage to the exterior wall.

[0010] Preferably, the exterior wall sample comprises an insulation board, a slot is provided on the insulation board, the depth of the slot is 1 / 2 of the thickness of the monitoring device, the monitoring device is inserted into the slot, and then a decorative layer is applied on the surface of the insulation board and the outside of the monitoring device.

[0011] Preferably, the decorative layer comprises a plaster mortar layer, a waterproof coating layer, a putty layer and a finishing layer, and the plaster mortar layer, the waterproof coating layer, the putty layer and the finishing layer are arranged in sequence from a side close to the insulation board to a side away from the insulation board.

[0012] Preferably, the thickness of the plastering mortar layer is greater than 1 / 2 of the thickness of the monitoring device, and the plastering mortar layer completely covers the monitoring device.

[0013] Preferably, the insulation board is cured for 3 days after the surface mortar layer is applied, and after the curing is completed, the waterproof coating layer is brushed on, and the putty layer is brushed on after curing the waterproof coating layer for 1 day, and then the putty layer is cured for 1 day and then the finishing layer is brushed on, and finally the finishing layer is cured for 7 days to complete the preparation of the exterior wall sample.

[0014] Preferably, the exterior wall sample is subjected to the following environment in the climate simulation box:

[0015] S101, spray the external wall samples with high temperature water, the water temperature is 15℃~70℃, and the cycle lasts for 20 days;

[0016] S102, leaving the exterior wall samples at 25°C for 2 days;

[0017] S103, continuously freeze and heat the exterior wall sample at a temperature of -20°C to 50°C for 5 days;

[0018] S104. Leave the exterior wall samples at 25°C for 7 days;

[0019] Repeat the above steps until the exterior wall sample shows bulging, wrinkles, cracks, or falls off and breaks, then stop the test and repeat the above test n times.

[0020] A monitoring device comprises a test box, wherein a temperature and humidity sensor is arranged inside the test box, a strain gauge is arranged on the outer wall of the test box, the temperature and humidity sensor and the strain gauge are connected to a recorder via a connecting line, and the recorder is used to record the data of the temperature and humidity sensor and the strain gauge.

[0021] Preferably, the test box comprises a frame, and grilles are fixedly provided on the sides of the frame, and flexible film-forming waterproof and vapor-permeable coating is applied on the grilles to seal the test box.

[0022] Preferably, the temperature and humidity sensor is suspended in the test box.

[0023] Preferably, the exterior of the temperature and humidity sensor is coated with a flexible film-forming waterproof and vapor-permeable coating.

[0024] The beneficial effects of adopting the above technical solution are:

[0025] In the present invention, by placing the test box in the insulation board, and brushing the surface mortar layer, waterproof coating layer, putty layer and finishing layer on the insulation board in sequence, the temperature and humidity sensor in the test box can monitor the temperature and humidity in the environment, and the outer wall of the test box is provided with a strain gauge, which can contact the insulation board and the surface mortar layer. When the insulation system is damaged, the strain gauge can monitor and record the strain value in time, and the average limit strain value ε can be obtained by calculation. avg , and the average ultimate strain value ε avg The risk warning strain value ε° can be obtained. When the monitored strain value is ≥ε°, the external wall insulation system is at risk of damage. Timely warning can be given and repairs can be carried out in time to reduce the risk of damage to the external wall insulation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the structure of the monitoring device of the present invention;

[0027] Figure 2 is a temperature and humidity data graph of the present invention;

[0028] Figure 3 It is a relationship diagram between strain and relative humidity when the wall cracks according to the present invention.

[0029] In the figure: 1 is the test box, 2 is the frame, 3 is the grid, 4 is the temperature and humidity sensor, 5 is the strain gauge, 6 is the connecting line, and 7 is the recorder. DETAILED DESCRIPTION

[0030] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] like Figure 1 As shown, a monitoring device includes a test box 1, wherein a temperature and humidity sensor 4 is provided in the test box 1 for monitoring the temperature and humidity in the environment, a strain gauge 5 is provided on the outer wall of the test box 1, and the temperature and humidity sensor 4 and the strain gauge 5 are connected to a recorder 7 through a connecting line 6, and the recorder 7 is used to record the data monitored by the temperature and humidity sensor 4 and the strain gauge 5; the test box 1 includes a frame 2, and the frame 2 is a cube or a rectangular parallelepiped structure, having six faces, and the six faces respectively include a top face, a bottom face and four side faces, and the six faces of the frame 2 are all provided with There is a corrosion-resistant metal grille 3, which can be made of stainless steel. The metal grille 3 supports the frame 2 to prevent the frame 2 from deforming. The six surfaces of the test box 1 are brushed with flexible film-forming waterproof and vapor-permeable coatings, so that a protective film is formed on the side of the test box 1 and it has waterproof performance, while also allowing water vapor in the environment to pass through. The temperature and humidity sensor 4 can monitor the humidity in the air. The flexible film-forming waterproof and vapor-permeable coating is a water-based acrylic flexible vapor-permeable waterproof coating. Four strain gauges 5 are provided, and the four strain gauges 5 are respectively located on the four sides of the test box 1.

[0034] Furthermore, the outside of the temperature and humidity sensor 4 is coated with a flexible film-forming waterproof and breathable coating, which completely wraps the temperature and humidity sensor 4, so that the temperature and humidity sensor 4 has a waterproof function, and can also monitor the temperature and humidity in the environment; in addition, the temperature and humidity sensor 4 is connected to the connecting line 6, and the connecting line 6 passes through the side wall of the test box 1 and is connected to the recorder 7 located outside the test box 1. The joints between the connecting line 6 and the side wall of the test box 1 and the connection points between the connecting line 6 and the temperature and humidity sensor 4 are sealed by applying a flexible film-forming waterproof and breathable coating to ensure the waterproof effect of the inside of the test box 1 and the connecting line 6. After the temperature and humidity sensor 4 is installed and the test box 1 is coated with the flexible film-forming waterproof and breathable coating, the test box 1 is left to stand for 24 hours, and then the strain gauge 5 is mounted on the test box 1.

[0035] Furthermore, the temperature and humidity sensor 4 is suspended in the test box, and a fixing rope can be tied to the temperature and humidity sensor 4. The fixing rope is a corrosion-resistant fixing rope. The other end of the fixing rope is connected to the grille 3 on the test box. The temperature and humidity sensor 4 can be suspended in the test box 1. In order to make the temperature and humidity sensor 4 more stable, multiple fixing ropes can be tied to the temperature and humidity sensor 4, and the multiple fixing ropes can be tied to the grille 3 in different directions.

[0036] In another embodiment, the temperature and humidity sensor 4 can also be fixedly connected to the grille 3 through a connecting rod, one end of the connecting rod is fixedly connected to the temperature and humidity sensor 4, and the other end is fixedly connected to the grille 3, so that the temperature and humidity sensor 4 is suspended in the air. The connecting rod can be made of plastic material, which has a corrosion-resistant effect.

[0037] Furthermore, the outside of the strain gauge 5 is coated with a flexible film-forming waterproof and vapor-permeable coating to waterproof the strain gauge. After the flexible film-forming waterproof and vapor-permeable coating completely wraps the strain gauge 5, the strain gauge 5 is fixedly arranged on the four sides of the test box 1. The strain gauge 5 is connected to the recorder 7 through the connecting line 6. The flexible film-forming waterproof and vapor-permeable coating is coated on the connecting line 6 to improve the waterproof effect of the connecting line 6. The connection between the connecting line 6 and the strain gauge 5 is also coated with the flexible film-forming waterproof and vapor-permeable coating. The connecting line 6 can transmit the strain value monitored by the strain gauge 5 to the recorder 7 for recording.

[0038] A method for monitoring damage of a building exterior wall insulation system comprises the following steps:

[0039] S1. Make an exterior wall sample, connect the monitoring device to the exterior wall sample, put the exterior wall sample into a climate simulation box, adjust the climate simulation box to simulate different environments and repeat n times. The monitoring device can monitor the limit strain value when the exterior wall sample is damaged, and obtain the limit strain value ε1~ε2 when the exterior wall sample is cracked. n ;

[0040] S2, according to the obtained limit strain value ε1~ε n Calculate the average ultimate strain value when the exterior wall is damaged Then calculate based on the average ultimate strain value Among them is Absolute deviation value;

[0041] S3, when , then remove the average limit strain value ε of this group of data avg Recalculate; when two or more groups of limit strain values ​​ε i >20%×ε avg When the limit strain value ε of group 1 or below is i >20%×ε avg When ε1~ε5, the average ultimate strain value ε is calculated avg ;

[0042] S4. Calculate the risk warning strain value ε°=20%×ε avg When the monitored strain value is ≥ε°, there is a risk of damage to the exterior wall. In this step, the monitored strain value is the average of the strain values ​​monitored in real time by the four strain gauges.

[0043] In step S1, the exterior wall sample includes an insulation board, and a slot is opened on the surface of the insulation board. The depth of the slot is 1 / 2 of the thickness of the monitoring device, and the length and width of the slot are respectively the same as the length and height of the test box 1. Therefore, after the monitoring device is inserted into the slot, the test box 1 can be clamped in the slot. Then, a decorative layer is brushed on the surface of the insulation board and the outer side of the monitoring device. After the decorative layer is brushed, since strain gauges are provided on the four sides of the test box 1, one of the strain gauges is in contact with the bottom surface of the insulation board slot, and the strain gauge on the opposite side is in contact with the decorative layer. Half of the strain gauges on the other two sides are in contact with the insulation board, and the other half are in contact with the decorative layer. By adjusting the climate to simulate the inward environment, damage is caused between the decorative layer and the insulation board, and the experiment is considered to be completed. When the damage occurs, the strain values ​​of the four strain gauges are recorded and the four strain values ​​are averaged, and the resulting value is the limit strain value ε n In the present invention, the number of experiments is 5, so 5 groups of limit strain values ​​ε1~ε5 can be obtained.

[0044] Furthermore, the decorative layer includes a plaster mortar layer, a waterproof coating layer, a putty layer and a finishing layer, and the plaster mortar layer, the waterproof coating layer, the putty layer and the finishing layer are arranged in sequence from the side close to the insulation board to the side away from the insulation board. The plaster mortar layer can be applied by brushing with cement mortar, the waterproof coating layer and the putty layer can be applied by brushing with waterproof coating and putty powder purchased on the market, and the finishing layer is applied by brushing with real stone paint.

[0045] Furthermore, the thickness of the plaster mortar layer is greater than 1 / 2 of the thickness of the monitoring device, and the plaster mortar layer completely covers the monitoring device. Therefore, one of the strain gauges on the four sides of the test box 1 is in contact with the plaster mortar layer, and the other two opposite strain gauges are half in contact with the insulation board and the other half in contact with the plaster mortar layer.

[0046] Furthermore, after a slot is opened in the insulation board and the test box 1 is inserted into the slot, a mortar layer is applied to the insulation board and the test box 1 so that the mortar layer completely wraps the test box 1. The insulation board is cured for 3 days after the mortar layer is applied. After the curing is completed, a waterproof coating layer is applied. After the waterproof coating layer is cured for 1 day, a putty layer is applied. After the putty layer is cured for 1 day, a finishing layer is applied. Finally, the finishing layer is cured for 7 days to complete the preparation of the exterior wall sample. The curing is performed by standing in an environment with a temperature of 25°C and a humidity of 50%.

[0047] Furthermore, the climate simulation box may be the climate simulation box used in application number CN202311842636.6, and the exterior wall sample piece is subjected to the following environment in the climate simulation box, causing the exterior wall sample piece to crack and break:

[0048] S101, spray the external wall sample with high temperature water, the water temperature is 15℃~70℃, and the cycle is 20 days, wherein the water temperature is gradually increased from 15℃ to 70℃ in one day, which is one cycle, and the external wall sample is sprayed with high temperature water for 20 days, which is 20 cycles;

[0049] S102, leaving the exterior wall samples at 25°C for 2 days;

[0050] S103, the external wall sample is continuously frozen and heated at a temperature of -20°C to 50°C for 5 days, wherein the ambient temperature is gradually raised from -20°C to 50°C within one day, which is one cycle, and the external wall sample is continuously frozen and heated for 5 days, which is 5 cycles;

[0051] S104. Leave the exterior wall samples at 25°C for 7 days;

[0052] The above steps S101 to S104 are continuously repeated until the exterior wall sample appears bulging, wrinkling, cracking or falling off, etc., and the test is stopped. When the exterior wall sample appears bulging, wrinkling, cracking or falling off, etc., one experiment is completed, and the above experiment is repeated n times. In the present invention, the above experiment is repeated 5 times. Each time the exterior wall sample appears bulging, wrinkling, cracking or falling off, the strain value recorded by the strain gauge at this moment is the limit strain value. The data recorded in the experiment are as follows: Figure 2 and Figure 3 As shown in the table.

[0053] It should be noted that after the insulation board is brushed with the surface mortar layer, waterproof coating layer, putty layer and finishing layer, although the strain gauge is only in contact with the surface mortar layer, due to the different materials between the layers, the shrinkage coefficients between the layers are different. Therefore, when one layer is damaged, it can cause the damage of the other coatings. The strain gauge can record the strain value at this moment in time; and by Figure 2 and Figure 3 It can be concluded that in the heating and freezing (-20℃~50℃) cycle of the exterior wall weathering experiment, as the relative humidity increases, the strain changes from positive to negative and then the absolute value gradually increases until the exterior wall cracks. This phenomenon shows that the accumulated water inside the exterior wall due to spraying is frozen at -20℃, gradually evaporates during the heating process, and a certain amount of water vapor accumulates in the exterior wall insulation layer, waterproof layer, and protective layer. The pressure formed by the water vapor causes the weak points of the exterior wall protective layer to deform from the inside to the outside, and eventually the deformation is greater than the cracking strain limit of the protective layer material, resulting in the cracking of the exterior wall.

[0054] After the above experiment has yielded a monitoring method for the damage of the exterior wall insulation system, the method can be applied in practice to monitor the damage of the exterior wall insulation system of the building in a timely manner. The monitoring device is installed in the exterior wall insulation system of the building, and the recorder is connected to an external computer. By setting a risk warning strain value and comparing the risk warning strain value with the average strain value calculated by actual monitoring, when the actual monitoring average strain value reaches the risk warning strain value, an alarm is issued and repairs are carried out in a timely manner.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for monitoring damage of a building exterior wall insulation system, characterized in that: The following steps are involved: S1. Make an exterior wall sample, connect the monitoring device to the exterior wall sample, put the exterior wall sample into a climate simulation box, adjust the climate simulation box to simulate different environments, repeat n times under the same conditions, and the monitoring device can monitor the ultimate strain value when the exterior wall sample is damaged, and obtain the ultimate strain value ε1~ε2 when the exterior wall sample is cracked. n ; S2, according to the obtained limit strain value ε1~ε n Calculate the average ultimate strain value when the exterior wall is damaged Then calculate based on the average ultimate strain value S3, when , then remove the average limit strain value ε of this group of data avg Recalculate; when more than two groups of limit strain values ​​ε i >20%×ε avg When the limit strain value ε of 2 or less groups is i >20%×ε avg When the average limit strain value ε is calculated avg ; S4. Calculate the risk warning strain value ε°=90%×ε avg ,When the monitored strain value is ≥ε°, there is a risk of damage to the exterior wall.

2. A method for monitoring damage of a building exterior wall insulation system according to claim 1, characterized in that: The exterior wall sample comprises an insulation board, a slot is provided on the insulation board, the depth of the slot is 1 / 2 of the thickness of the monitoring device, the monitoring device is inserted into the slot, and then a decorative layer is applied on the surface of the insulation board and the outer side of the monitoring device.

3. A method for monitoring damage of a building exterior wall insulation system according to claim 2, characterized in that: The decorative layer comprises a plaster mortar layer, a waterproof coating layer, a putty layer and a finishing layer, and the plaster mortar layer, the waterproof coating layer, the putty layer and the finishing layer are arranged in sequence from a side close to the insulation board to a side away from the insulation board.

4. A method for monitoring damage of a building exterior wall insulation system according to claim 3, characterized in that: The thickness of the plastering mortar layer is greater than 1 / 2 of the thickness of the monitoring device, and the plastering mortar layer completely covers the monitoring device.

5. A method for monitoring damage of a building exterior wall insulation system according to claim 4, characterized in that: The insulation board is cured for 3 days after the surface mortar layer is applied, and after the curing is completed, the waterproof coating layer is brushed on, and the putty layer is brushed on after curing the waterproof coating layer for 1 day, and then the finishing layer is brushed on after curing the putty layer for 1 day. Finally, the finishing layer is cured for 7 days to complete the preparation of the exterior wall sample.

6. A method for monitoring damage of a building exterior wall insulation system according to claim 1, characterized in that: The exterior wall samples were subjected to the following conditions in the climate simulation chamber: S101, spray the external wall samples with high temperature water, the water temperature is 15℃~70℃, and the cycle lasts for 20 days; S102, leaving the exterior wall samples at 25°C for 2 days; S103, continuously freeze and heat the exterior wall sample at a temperature of -20°C to 50°C for 5 days; S104. Leave the exterior wall samples at 25°C for 7 days; Repeat the above steps until the exterior wall sample shows bulging, wrinkles, cracks, or falls off and breaks, then stop the test and repeat the above test n times.

7. A monitoring device, characterized in that: The monitoring method applied to any one of claims 1 to 6 comprises a test box (1), wherein a temperature and humidity sensor (4) is provided inside the test box (1), a strain gauge (5) is provided on the outer wall of the test box (1), the temperature and humidity sensor (4) and the strain gauge (5) are connected to a recorder (7) via a connecting line (6), and the recorder (7) is used to record data of the temperature and humidity sensor (4) and the strain gauge (5).

8. A monitoring device according to claim 7, characterized in that: The test box (1) comprises a frame (2), and grilles (3) are fixedly arranged on the sides of the frame (2). A flexible film-forming waterproof and vapor-permeable coating is applied on the grilles (3) to seal the test box (1).

9. A monitoring device according to claim 8, characterized in that: The temperature and humidity sensor (4) is suspended in the test box (1).

10. A monitoring device according to claim 9, characterized in that: The exterior of the temperature and humidity sensor (4) is coated with a flexible film-forming waterproof and vapor-permeable coating.

Images