Laser vibration test inspection method for detecting pasting quality of thin plaster heat insulation system

Abstract

The invention discloses a vibration method detection method for detecting the pasting quality of a thin plaster heat insulation system. An EPS plate thin plastering external thermal insulation system has good thermal insulation performance, is widely applied at home and abroad, and is one of important thermal insulation systems for wall energy-saving design. When an EPS heat insulation plate is pasted, the plate surface is knocked, patted and vibrated, consequently the adhesive can fall off, virtual adhesion is caused, and a cavity becomes larger, a constructor can even forcefully press one side of the plate, so that the other side of the plate tilts, the plate surface of one side is not adhered, and the cavity becomes larger. Under the condition, the natural vibration properties of the system, especially the first-order mode, are greatly changed. According to the vibration method detection method, the pasting quality of the thin plaster heat insulation system can be detected without a damage test, and the pasting quality is judged through detection and analysis of a non-contact laser vibration meter and a finite element model.

Description

technical field [0001] The invention relates to the field of construction engineering quality detection, in particular to the technical field of quality detection of external wall thermal insulation systems. Background technique [0002] With the advancement of national energy conservation and emission reduction work, external wall insulation technology has been widely used. However, affected by factors such as building structure, climatic conditions, system materials, construction technology, and construction management, accidents such as hollowing, cracking, and falling off of the external wall thermal insulation system (hereinafter referred to as "external thermal insulation system") often occur, causing personnel Casualties, economic losses, and bad social impact. [0003] At present, a large number of actual cases of hollowing and falling off have been accumulated in external wall insulation renovation projects all over the country. Most of the defect problems are part...

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Problems solved by technology

Because the insulation material is a high-attenuation material, the stress wave attenuates seriously when it propagates in the insulation layer, so this method can only be used to detect the defects between the decorative layer and the insulation layer, and the detection effect on the defects between the insulation layer and the base layer is not good. good

At the same time, since the hardness of the external thermal insulation system is lower than that of concrete, it is easy to be damaged when an impact force is applied to the surface of the external thermal insulation system during the detection process.

[0007] Infrared thermography is mainly used in the detection of thermal defects in external thermal insulation systems, but there are still the following problems in the detection of physical defects such as hollowing and shedding: ① infrared thermal imaging can only qualitatively analyze whether there are internal defects in external thermal insulation systems and The approximate location of the defect cannot quantify the size, shape, location and severity of the defect, and it is highly dependent on experience, so it is difficult to make targeted maintenance or remediation suggestions; ②The external thermal insulation system is composed of multi-layer composite materials, and the surface infrared radiation The impact is relatively large, and there are still many technical problems to be solved in quantitative testing and analysis

However, due to the serious attenuation of ultrasonic waves when propagating in the insulation layer, and the higher the frequency, the more serious the attenuation, the ultrasonic longitudinal wave signal cannot be transmitted through the insulation layer to the base wall, making the ultrasonic phased array technology unable to detect the distance between the insulation layer and the wall. defect

At the same time, due to circuit crosstalk, piezoelectric wafers and aftershocks of the shell, the ultrasonic probe has detection blind spots, usually 1% to 5% of the range, which makes it impossible for ultrasonic phased array technology to detect defects between the finish layer and the insulation layer

[0009] Ground-penetrating radar detection technology can reflect and distinguish the interface of different underground media layers, and calculate its depth, thickness and media properties. It has the advantages of high resolution, non-destructive, high efficiency, and strong anti-interference ability. It has been widely used in archaeology and non-destructive engineering quality. Detection, environmental engineering and many other fields have application potential in the detection of hollowing defects between the decorative layer and the insulation layer, but the detection accuracy and sensitivity need to be further studied

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