Résumé:
Prediction of soil swelling characteristics and accurate quality estimation can be of
great consideration and contribution regarding site stability. Any concerned investigation is
correspondingly an advanced priority for project realization. Related inquiries allow
potential reduction concerning financial and technical charges damage prior to any urban
development. The determination of soil characteristics lead for a best recognition, and
allow for the best choice of foundation type adopted for each site. Thus, in any urban case
study, much gain can be made by team work recording and surveying the related data. In
the considered city of El Kouif, located at Tebessa in Algeria, several buildings have been
built mainly on expansive soils. Observations indicate different severe damages which
were caused mostly in the nearby structures. These damages are characterized by
deflection and failure of walls. Lateral and vertical displacements evidences support the
presence of shear movements and subsidence. The scale up of these movements occurrence
can reach millimetric shifting dimension.
Laboratory analysis was executed on soil study, results and discussion of those
analysis show that the soil study are characterized by a large range of geotechnical
parameters. Geotechnical classification shows that the soils are classified in the high to
very high domain of swelling.
Ground and subsurface risk activity affecting El Kouif city site are also related to the
presence of destructive chemical components such as sulfates. The chemical by
fluorescence, and mineralogical analysis (XRD), emphasizing, at the same time, the high
percentage of sulfate with the clay minerals (smectite). The sulfate occurrence is
illustrated through generally gypsum minerals concentration present in the concerned soil.
Source for these chemical products expansion might be associated to historical event: the
city of El Kouif was the field of phosphates mining area in addition to established
phosphate extraction plant. Thus, determination of soil characteristics and involvement of
chemical components turn out to be the main objectives in this investigation.
