Using XRD and SEM analysis, the types and morphology of autoclaved aerated concrete (AAC) hydration products in different water-to-binder ratio (w/b) and different autoclaved system were studied. Strength test shows that, Using w/b=0.25 and autoclaved curing 190°C for 8h, AAC with dry density 765kg/m3 and compressive strength 7.5MPa was made. XRD and SEM analysis indicate that, the higher the autoclaved temperature is, the smaller the size of hydration products (most of them are tobermorite and hydrogamet) is, and the crystallinity has a little increase; with the extension of autoclaved time, the size of products is smaller, the crystallinity is first increased and then decreased, the crystal form of tobermorite turns 1.1nm into 1.4nm; the less the w/b is, the smaller the size of products is, and the higher the crystallinity is, and tobermorite turns 1.1nm into 1.4nm.

At present, masonry and plaster of AAC blocks are still carried out by traditional construction methods which often lead to some quality defects such as cracking and leaking in the wall and hollowing and spalling in the plaster layer, etc. and hinder greatly the popularization and application of AAC blocks. On the basis of the characteristics of AAC blocks and the dry masonry thin-bed mortar, a kind of high performance dry-mixed Mortar for dry masonry process of AAC blocks was developed. The mortar has excellent workability, high water-retention, property, good mechanical properties and good construction properties. It solves the problems caused by traditional construction methods. The mechanism for these is discussed.