Suitability of Phragmites for lightweight concrete

In order to test the suitability of Phragmites australis as base material for lightweight concrete, reed straw was harvest from zje protected mire area of the National Park Narew, NE Poland. In March 2004, plant material was collected along a transect extending from the margin of valley, across the floodplain up to the river. Studies on morphological properties like shoot length. shoot diameter, number of nodes. Thickness of sclerenchyma rings and technical properties like bulk density, absorbing and binding of water were performed to elucidate the basis of the pressure stability (N mm-2) of concrete probes. Our results revealed that Phragmites growing far from the watercourse are charcterised by low bulk density, better water characteristics and consequently higher pressure stability of concrete, reaching up to 0.5 N mm-2. Phragmites growing close to the riverbank revealed significantly higher bulk density (over 100 kg M-3), worse water features and as a consequence lower pressure stability of the concrete. The good parameters of obtained lightweight concrete blocs along with the rising industrial demand for cost effective, lightweight and robust insulating materials allow us to predict, that Phragmites has a great potential as feedstock for building materials.