Formulation of bentonite cement groutfor sealing walls

Abstract

Marine and land environment is deeply affected by NPKcompany phosphogypsum storage in Sfax city. A part ofTaparura project aims to confine this pile of partially ortotally heavy metal pollution by creating a sealing made up of bentonite waterproof cement. This study isabout a methodology formulation of cement bentonitegrout to build the screen. The physical properties of freshand hardened material as well as its mechanical propertieswere determined. First, a synthesis bibliographyintroduces the bentonite and cement properties materialcomposition as well as the methods of formulation andstandardized tests. Second, an experimental study wascarried out to formulate the cement bentonite material.This study has permitted the determination of b/wb, b/cand wt/cratios of the BC grout and the strengthproperties of the projected grout. Moreover, the propertiesof grout in fresh state of bentonite-cement are in a goodcorrelation with the desired conditions for the screenexecution. The vertical permeability obtained is so lowwhich limits greatly the flows through the screen. TheYoung modulus of cement bentonite material is near thesoil modulus which conducts to the same strains in bothsoil and screen thereby reducing micro cracks in screen