A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Shrinkage-reduced high performance concrete
Even though there are numerous research projects on high performance normal weight concrete (HPC) only little is known on the long-term behaviour of those concrete whose dense aggregates content is partly (HPLWAC) or completely (HPLC) replaced by lightweight aggregates. In this cases the interaction of a high performance matrix and the water stored in the pore system of the LWA and their influences on creep and especially on shrinkage were of particularly interest. In pursuance of this aim a comparison between high performance concrete without and with LWA - both in the same range of strength - was needed. From the test results the following conclusions can be drawn: The lightweight aggregate Liapor 9.5 can be used for a reliable production of HPLWACs and HPLCs due to its spherical shape and the relatively dense outer shell. The water absorption of the analysed LWA is approximately 6.0 mass-% during a mean mixing and compaction time. The LWA demonstrates a high density/strength potential; a concrete with a dry density of 1.8 kg/dm3 and a compressive strength of 100 N/mm2 was able to be produced under laboratory conditions. A LWA content of around 30% reduces the modulus of elasticity at equal compressive strength by 25%. The internal moisture conditions were able to reduce or elaminate autogenous shrinkage, whereas the drying shrinkage was reduced drastically due to the same reason. Total creep deformation is basically influenced by the matrix properties and less by the use of LWA. Creep recovery of high performance concrete using LWA is higher than of HPC without LWA and takes place even after a observed period of 125 days.
Shrinkage-reduced high performance concrete
Even though there are numerous research projects on high performance normal weight concrete (HPC) only little is known on the long-term behaviour of those concrete whose dense aggregates content is partly (HPLWAC) or completely (HPLC) replaced by lightweight aggregates. In this cases the interaction of a high performance matrix and the water stored in the pore system of the LWA and their influences on creep and especially on shrinkage were of particularly interest. In pursuance of this aim a comparison between high performance concrete without and with LWA - both in the same range of strength - was needed. From the test results the following conclusions can be drawn: The lightweight aggregate Liapor 9.5 can be used for a reliable production of HPLWACs and HPLCs due to its spherical shape and the relatively dense outer shell. The water absorption of the analysed LWA is approximately 6.0 mass-% during a mean mixing and compaction time. The LWA demonstrates a high density/strength potential; a concrete with a dry density of 1.8 kg/dm3 and a compressive strength of 100 N/mm2 was able to be produced under laboratory conditions. A LWA content of around 30% reduces the modulus of elasticity at equal compressive strength by 25%. The internal moisture conditions were able to reduce or elaminate autogenous shrinkage, whereas the drying shrinkage was reduced drastically due to the same reason. Total creep deformation is basically influenced by the matrix properties and less by the use of LWA. Creep recovery of high performance concrete using LWA is higher than of HPC without LWA and takes place even after a observed period of 125 days.
Shrinkage-reduced high performance concrete
Schwindungsreduzierter Hochleistungsbeton
Schwesinger, P. (author) / Sickert, G. (author)
EUROMAT, EUROMAT, 1999 ; 28-34
2000
7 Seiten, 3 Bilder, 4 Tabellen, 4 Quellen
Conference paper
English
Shrinkage-Reduced High Performance Concrete
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Shrinkage‐Reduced High Performance Concrete
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Research - Shrinkage-reduced binders for high performance concrete, part 2
| British Library Online Contents | 2000
CONCRETE TECHNOLOGY - Research - Shrinkage-reduced binders for high performance concrete, part 2
| Online Contents | 2000