Study of the swelling properties of marl samples of the “Morne Delmas” geological formation using indirect and direct methods. Some effects of waste water on these properties

Kelly Guerrier, Dominique Boisson, Jean-François Thimus, Christian Schroeder

In the proceedings of: GeoRegina 2014: 67th Canadian Geotechnical Conference

Session: Soil Mechanics

ABSTRACT: Several cases of cracks in buildings recorded in the metropolitan area of Port-au-Prince (Haiti) are due to the presence of swelling clays in calcareous marls of the "Morne Delmas" formation which is a geological formation of the Pliocene. In addition, gaps in the sanitation system due to uncontrolled appropriation of land by a growing population have lead to pollution of soil by domestic and industrial sewage which accentuates the problem of swelling. This article presents the mineralogical and geotechnical methods to characterize the swelling of "Morne Delmas" marl and the impact of wastewater on it. RÉSUMÉ Plusieurs cas de fissurations de bâtiments enregistrés dans la région métropolitaine de Port-au-Prince (Haïti) sont dûs à la présence d'argiles gonflantes dans les marnes calcaires de la formation « Morne Delmas » qui est une formation géologique du Pliocène. De plus, les lacunes du système d'assainissement dues à l'occupation non maîtrisées des terrains par une population croissante entraînent une pollution des sols par les eaux usées domestiques et industrielles ce qui accentue le problème de gonflement. Cet article présente les méthodes minéralogiques et géotechniques utilisées pour caractériser le gonflement des marnes de « Morne Delmas » et l'impact des eaux usées sur celui-ci. 1 INTRODUCTION The problem of swelling clayey soils frequently catches the attention of engineers and researchers in geotechnics by the fact that the repair cost of the damaged structures is very high (Vincent et al., 2008). This problem may increase with soil pollution resulting from uncontrolled occupation of spaces. Port-au-Prince, originally designed to accommodate 250,000 people, now has 2 million inhabitants. The consequences were the spontaneous expansion of the city on neighboring land without any prior planning and in poor sanitary conditions. The lack of adequate sanitation in these residential areas forces sewage to borrow a natural flow network such as gullies. These waters, laden with pollutants of all kinds: water washing, organic waste ... seeps into the ground. Figure 1 shows the evolution of the urban sprawl of the population of Port-au-Prince since the founding of the city from 1750 to 1996. Urban spot in 1996 is far more extensive than that of 1750. The drainage system is present (yellow area in the Figure 2) in the area built in 1750, but almost totally absent outside (Holly, 1999). All wastewater of these populations are directly discharged into the ground which is a major source of pollution. Figure 1 : Evolution of urban sprawl of Port-au-Prince between 1750 and 1996 (Holly, 1999)

RÉSUMÉ: of the swelling properties of marl samples of the 'Morne Delmas' geological formation using

Access this article:
Canadian Geotechnical Society members can access to this article, along with all other Canadian Geotechnical Conference proceedings, in the Member Area. Conference proceedings are also available in many libraries.

Cite this article:
Kelly Guerrier; Dominique Boisson; Jean-François Thimus; Christian Schroeder (2014) Study of the swelling properties of marl samples of the “Morne Delmas” geological formation using indirect and direct methods. Some effects of waste water on these properties in GEO2014. Ottawa, Ontario: Canadian Geotechnical Society.

@article{GeoRegina14Paper367,author = Kelly Guerrier; Dominique Boisson; Jean-François Thimus; Christian Schroeder,title = Study of the swelling properties of marl samples of the “Morne Delmas” geological formation using indirect and direct methods. Some effects of waste water on these properties,year = 2014}