At present, in various parts of the promotion and application of a variety of exterior insulation system technology and products in the process of building walls more or less hollowing, cracks or shedding, etc., not only affect the energy efficiency of buildings, but also directly affect To the community’s recognition and application of this technology. Therefore, the external wall insulation reliability and safety issues must be brought to our attention, need to take effective measures to solve.
In order to ensure the external insulation system reliability and security, in the use of adhesive fixed basis, and then through the mechanical anchor reinforcement is necessary. As early as July 1, 2003 implementation of the “expansion of polystyrene board thin plaster external insulation system,” the national standard, the external wall insulation system used in the development of anchors have strict performance requirements, from which it is easy to see the role of anchors.
As we all know, the external wall insulation is a system, it is not by a single category of products. Currently there are two commonly used systems, one kind of bolt with the entire system, the other is connected with the bracket insulation system. Select insulation anchors to be involved in the substrate, the thickness of insulation, insulation materials, as well as system applications. The anchor bolt into the substrate after the main friction, convex combination (mechanical locking), chemical bonding three forces to bear the load. Domestic use is the most after the two. In the European countries, the application of anchors for many years, there are strict standards, such as the use of the substrate, how to plaster layer or finishes in the existing surface insulation layer are provided. China draws on foreign standards, in the relevant provisions of the provisions of more than a certain height of the building through the anchor bolts to connect to the foundation of the above part of the insulation surface must also be used insulation anchor.
On the installation of insulation anchor, there are two main ways. One is a percussive installation, convenient and quick, do not need additional installation tools. The other is screw-in installation, the need to use special installation tools and the appropriate installation techniques. But screw-in mounting can provide higher bearing capacity and safety. In the installation process, will be screwed into the disc inside the insulation cap position (insulation cap and the disc is flat), can be a good way to avoid heat loss. In addition, we have to consider the thickness of the insulation board, but also consider the plaster layer thickness. Because it involves some of the actual installation, installation of anchors must pay attention to playing the hole, the hole must be longer than the length of the insulation anchor. It is worth noting that the installation of the nail and the disc to install separately, first knock down the disc, then nail into. Currently on the market there are already in the design of the screw to play with the role of the safety foot to prevent disc cracking products, nails and discs are nailed together.
From the perspective of the structure of the building, the composite wall insulation system along the wall thickness direction is composed of a variety of different materials, and these have different thermal conductivity of the materials were in different temperature fields, thermal expansion and contraction degree and direction Are not the same, the resulting stress load is very complex. In addition, these materials in different wind and negative pressure field, the force size and direction will change due to changes in the outside world. Therefore, the composite wall insulation system load characteristics of non-linear, three-dimensional, time-varying, if not take feasible measures, problems will inevitably arise. Therefore, the implementation of insulation measures on the building, the increase in the anchor is an essential process, the only way to ensure the system safe and reliable.