Thermally induced changes in microstructure and their effects on the mechanical parameters of AAC

Summary: Investigations into the thermally induced changes in the microstructure of autoclaved aerated concrete (AAC) were compared with the systematic determination of the parameters of high temperature stressing of the three currently most widely used types of aerated concrete (P2-0.35; P2-0.4 and P4-0.5) to gain an insight into how masonry made of aerated concrete would behave in the case of fire. The determination of temperature-dependent building material parameters in AAC has made a contribution to the creation of a systematic material database for the application of engineering methods of structural fire protection in accordance with Eurocode 6, Part 1–2.

1 Introduction and present state of knowledge

Autoclaved aerated concrete (AAC) is an inorganic, mineral, walling material that unites a very favourable combination of the parameters of bulk density, compressive strength and thermal conductivity. Quartz sand, lime and/or cement as the binder, gypsum and/or anhydrite (depending on the mix formulation) and water are required for its production. The building material acquires its characteristic porous structure through the addition of aluminium powder, which reacts in the aqueous alkaline environment with the evolution of hydrogen and foams the...

Related articles:

Issue 10/2018 UNIVERSITY OF APPLIED SCIENCES NUREMBERG GEORG SIMON OHM

Effects of fumed silica on material engineering parameters of external rendering, with special emphasis on thermal conductivity and compressive strength

1 Introduction and objectives The main prerequisite for energy-efficient operation of residential and non-residential buildings is that they are appropriately insulated against heat loss. While...

more
Issue 9/2018 UNIVERSITY OF APPLIED SCIENCES NUREMBERG GEORG SIMON OHM

Improving the thermal insulation properties of thin-bed mortar|Part II: Effects of selected admixtures and combinations thereof on material properties, in particular pore-size distribution, thermal conductivity and compressive strength

1 Introduction and objectives The main objective of the subject research work was to develop a new type of thin-bed mortar characterized by reduced thermal conductivity with no loss of compressive...

more
Issue 3/2017 OTTO VON GUERICKE UNIVERSITY MAGDEBURG

Thermophysical properties of lime as a function of origin (Part 4): Thermal conductivity

1 Introduction The calcination behavior of limestone, which is a natural raw material, depends strongly on the origin. In this multi-part series, the thermo-physical material properties of limestone...

more
Issue 3/2020 UNIVERSITY OF KASSEL

Raising the quality of calcium silicate units with simultaneous reduction of production costs using Statistical Design of Experiments (DoE)

1 Introduction Calcium silicate units are masonry blocks formed from burnt lime and silicate raw materials that are autoclaved in an atmosphere of high-pressure steam at approx. 200°C and 16 bar. The...

more
Issue 6/2018 University of applied sciences Nuremberg GEORG SIMON OHM

Improving the thermal insulation properties of thin-bed mortar Part I: Impact evaluations of various admixtures on material engineering parameters

1 Introduction Thin-bed cement mortar is often used for masoning up such precision-ground, monolithic wall-building materials as bricks, autoclaved aerated concrete units (Ytong), or building blocks...

more