The 1960's saw the beginning of rapid population growth in many cities world wide, accompanied by a demand for high speed, underground transport systems. Menard Bachy has been at the forefront in developing solutions for the challenging construction issues associated with many of the underground stations in these projects, performing soil consolidation grouting and diaphragm walling for station boxes and cut and cover tunnels.
Lisarow, Rail Bridge, New South Wales, Australia
This method of tunnel construction has proved to be ideal, where, due to space constraints, a motorway, main line railway or metro has to pass immediately below ground surface level, in urban areas. The method comprises the installation, from the existing ground surface, of parallel side walls (usually diaphragm walls) spanned by a cover slab enabling the early restoration of street level traffic. The tunnel is excavated once the cover slab has reached design strength requirements.
The most recent major projects of this type have been in Hong Kong, Singapore and the USA but equally many smaller projects have been completed.
Chatswood to Epping Rail Link, Sydney, New South Wales
Transport engineers are frequently confronted with highly compressible soils and are required to deliver cost effective design solutions. An example is that of roads crossing wetland or flood plains comprised of soft and often deep compressible soils, where it is necessary to either consolidate the in-situ soils or to install inclusions to improve the global soil modulus prior to embankment construction, in order to eliminate the risk of slope failure, either during construction or in the longer term.
Soil improvement is essential to minimise long term creep settlement and deliver a foundation that increases and preserves the service life of the future road pavement, reducing life cycle costs for the roadways and structures. Road embankments impose high surcharge loads to the foundation soil strata. The design of these foundations routinely requires intensive treatment to improve the soil strength criteria.
Sydney Airport Runway Extention, New South Wales
