1. Strength and stiffness of insulating glass

The strength of insulating glass refers to the ability of insulating glass to resist external load, and the stiffness refers to the ability of insulating glass to bear deformation. Obviously, after the glass material is given, such as ordinary flat glass or tempered glass, then according to the glass strength design theory, the breaking strength of the original glass is determined. Therefore, in order to improve the carrying capacity of insulating glass, it is necessary to make the bending and tensile stress of the glass surface smaller under the same load, which is related to the size of the insulating glass original sheet (the length, width, length-to-width ratio and thickness of the original sheet) and the thickness of the hollow layer. The load directly distributed to each piece of glass under the action of external load determines the carrying capacity of the insulating glass.

Since insulating glass is composed of two (or more) pieces of glass, the surrounding seal forms a sealed air layer. When one side of the glass is subjected to load, the glass on the stressed surface deforms and compresses the gas in the hollow layer. The pressure of the gas increases, and part of the load is transmitted to the other side of the glass. Two pieces of glass deform simultaneously.

2. Bearing characteristics of insulating glass under the failure state of the hollow layer

In the case of the gas seal of the hollow layer, the transmission of gas can transfer part of the external load to another piece of glass, but when the gas layer leaks, the gas of the hollow layer completely loses the function of transferring load. At this time, the load borne by the hollow glass is completely borne by the glass that is directly stressed. Obviously, the load bearing capacity of the insulating glass at this time will be significantly reduced.

3. The influence of ambient temperature and pressure difference on the bearing performance of insulating glass

Even if it is not subject to external load, due to the difference between the production regional environment and the use of the regional environment, it will also lead to the expansion or contraction of the gas in the hollow layer of the insulating glass, which directly leads to the deformation and additional stress of the two original pieces of glass, and will make the two pieces of glass bump together and even cause the glass to break.

In summary, the carrying capacity of insulating glass depends on the strength and stiffness of the glass plate and the tightness of the hollow layer; Under uniform load, the force on the outside and inside sides of the insulating glass is different, the force on the outside glass is large, and the force behind the glass is small, and the smaller the size, the more obvious; When the side length of the insulating glass is more than 150 times the thickness, the force of the two sides of the glass tends to be close; After the gas leakage failure of the hollow layer, the bearing deformation performance of the hollow glass changes obviously. By applying concentrated load to the hollow glass, measuring the deflection of the inner and outer plates or the change of the thickness of the hollow layer, it can identify whether the middle air layer is well sealed. The test and field test results show that the method and the testing device can detect the sealing performance of insulating glass conveniently, quickly and reliably.