ERSS FOR THE JACKING AND RECEIVING SHAFTS
ERSS in the form of any structural system used to maintain the shape of excavation during excavation works, earth filling or cutting and is meant mainly for the construction of the jacking and receiving shafts.
There are different types of ERSS systems to be adopted during the construction stage depending on various ground conditions.
Typical Types of ERSS
Sheet Pile Shoring System
Using a crane or an excavator with vibro, sheet piles are driven to the required shape & depth before the excavation of ERSS. Walers & struts are installed to the required levels as per approved PE design.
Cast in situ Caisson – top down construction
Round caisson is excavated to a depth of 0.60M or 1.20m to the required outer diameter. After excavation, steel reinforcements are installed around the excavated sides as per PE design. A steel mould is installed for the internal formwork which is then casted. The process is repeated until the required formation level is reached.
Timber board shoring – shallow shafts
This system is the traditional method for shallow temporary working shafts. Timber boards of 8’x3’ is used to protect the excavated sides as excavation is carried out to the required formation level. Walers & struts are installed in accordance with the PE design.