P1:use glass to make load-bearing structure,但是glass容易产生裂缝。否认方法coating,违背使用glass的初衷
P2:方法tempering:break into more and smaller pieces than untempered glass
P3: primary concern: maintain the integrity? 解决方法Lamination,但它和tempering很难结合在一起
P4:寻求解决方法:①less expandable(could,作者可能不太看好这个方法)②adhesive(-)