Abstract
In the last years, many things have changed in the way a car is assembled, and undoubtedly one of the most evident aspects involved in such evolution refers to the mounting of glasses. Various bonding techniques have replaced mounting by means of weather strips. One of the consequences is that nowadays glasses are part of the car, subject to various stresses transmitted by the chassis, and the question becomes whether glasses are able to resist to such stresses. The answer to this question requires the use of strain/stress analysis techniques, usually employed on metallic structures, and based on electric resistance strain gauges (see fig. 1).
Since one of the most critical glass applications on a car is the multi-layer windscreen, a testing specification has been developed, considering the different phases of its life, starting from the bonding of the windscreen on the car to a typical defrosting operation, up to road simulations under various conditions.