GS Littlejohn, BSc(Eng), PhD, CEng, FICE, MIStructE, FGS. This paper was first published in GE’s March 1985 edition.
The use of chemicals in grouting evolved logically from cement grouting practice where direct injection of neat cement into fine fissures or small pores was only partially successful. At Thorne in Yorkshire, for example, two shafts started in 1909,came to a standstill at a depth of 150m due to heavy water ingress through porous sandstone which contained fine fissures. With a background of proven experience from Hatfield Colliery in 1911, the Belgian engineer Francois employed silicatisation at Thorne in 1913 and this commercial success established the process in engineering practice. The technique involved the injection of sodium silicate and aluminium sulphate solution, after which neat cement grout was injected with comparable ease.