Construction – Civil Engineering

Lime is a universal, structure-providing raw material. In the building industry its use is generally invisible: all of us live and move on lime without ever noticing.
The subsoil is improved by the addition of SCHAEFER KALK quicklime (CaO).
Asphalt properties are improved and its durability extended by adding SCHAEFER KALK lime hydrate and limestone powder.
Defined grading curves for foundations, base layers and asphalt mixes are available.

Subsoil improvement
In street and road building, lime is applied before any visible works begin: the addition of quicklime (CaO) improves the often uneven existing subsoil structure and establishes its load-bearing capacity for subsequent construction steps. Long ago the Romans already appreciated the advantageous properties of lime in the construction of their roads.
Quicklime is especially suited for the improvement of cohesive, very finely grained soils, as in these cases water content is high and load-bearing capacity is low. SCHAEFER KALK quicklime is employed to extract water from the soil. It is thereby safely bound, thus creating a compactible, stable sub base.
SCHAEFER KALK supplies natural lime qualities that improve the soil without polluting it with contaminants.  

Besides the standard addition of limestone granules and limestone powder in mastic asphalt, the use of lime hydrate in asphalt is increasing in significance. Because of regional differences in rock formations, a consideration of the affinity of bitumen and rock is important.
A further positive effect of adding SCHAEFER KALK lime hydrate is the improvement of bitumen properties: calcium significantly increases durability by inhibiting oxidative processes, which is reflected in a lowered increase in ring and ball values over time. On this subject, you can find a report about the use of lime hydrate in asphalt in SCHAEFER KALK’s own test road in the download section.
SCHAEFER KALK lime hydrate effectively prevents swelling in asphalt.
SCHAEFER KALK produces different limestone grain sizes. The product palette ranges from coarse gravel to finely ground hard limestone powder. The applications are as diverse as the grain size:
Gravel: for the frost proof production of load-bearing bases with a low proportion of fine grain.
Fine sand: for the secure filling of shafts and conduits with a low proportion of oversize grain.
Quality-monitored crushed limestone: as a substrate for e.g. paving work, easily compacted and stable.
Defined particle sizes: for the recipe-conforming production of e.g. asphalt mixtures and concretes.
Limestone powder: consistent quality and a high level of purity guarantee the safe production of mastic asphalt.