SYNOPSIS

In hot and arid regions, the presence of shallow and saline water table leads to the formation of salt-laden flat ground typically known in Arabic as “sabkha”. Sabkha soil planes are generally formed in regions where rate of evaporation is higher than the rate of precipitation (Al-amoudi, 1999; AL-Amoudi, Aiban, & Al-Abdul Wahhab, 1999; Alhumimidi, 2020; Baghabra Al-Amoudi & Abduljauwad, 1995a). This phenomenon is seen in many different parts of south America, USA, northern Africa, and the Arabian Gulf region (Saudi Arabia, Qatar, Kuwait, and United Arab Emirates). In Gulf region, sabkha soils cover approximately 50,000 km2 along the coastline within 50km distance from seashore (Akili, 2006; Alnuaim & El Naggar, 2014a). In general, these sabkha flats are constituted by cemented and uncemented layers of sand and silty material, mixed with lenses of clay and mud. The cementing agents generally found are calcium carbonate and / or digenetic minerals such as gypsum and anhydrite. In addition to the coastal regions, Sabkha is also found away from seashores. The former is termed as coastal sabkha and the one found inlands is termed as continental sabkha. (Al-amoudi, 1999). Construction activities on sabkha soils have encountered serious problems and challenges (Akili, 2006; Alnuaim & El Naggar, 2014b). Hence, characterization and stabilization of sabkha has not only attracted the scientific community but also the geotechnical consultants and government authorities. The most likely problems found in sabkha sediments include excessive settlement and abrupt loss of shear strength on account of dissolution of salts due to precipitation or upsurge of ground water (Akili, 2006; Baghabra AlAmoudi & Abduljauwad, 1995b). Additionally, this ultra-saline environment creates highly corrosive medium for reinforced concrete used in foundations. This paper would present the type and formation of sabkha soils, their geotechnical problems, some case studies, and current practices to improve its geotechnical properties.


BIODATA OF SPEAKER

Dr. Mohd Ahmadullahh Farooqi

Dr Mohd Ahmadullah Farooqi is currently working as Assoc. Prof. in the Department of Building Engineering, College of Architecture and Planning, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia. He has over 22 years of teaching experience, including three years in Australia. He has extensive research experience, and his areas of research focus are: Micro-Macro modelling of geomaterials using Micro CT and Nano CT Scanning techniques, conversion of Micro CT Image dataset to FE models, virtual testing of building materials through X-ray Micro CT images, ground improvement using micropiles, stone columns, underground structures modelling, sustainable foundation systems, transport geotechnics, transportation, and traffic engineering.

He obtained PhD degree in Geotechnical Engineering from the University of Newcastle and worked at the Australian Center for Microscopy and Microanalysis (ACMM), formerly known as Electron Microscope Unit (EMU) at the University of Sydney, Australia, for his work related to Micro CT scanning. Besides that, he has also worked in the Stochastic Modelling of landslide in the University Sains Malaysia (USM), Penang, Malaysia. Dr Farooqi has published several research papers in national and international peer reviewed journals and conferences and contributed book chapters. He has delivered several keynote lectures on the application of Micro CT scanning modality in civil engineering, sustainable smart cities, etc. In the role of a geotechnical consultant, he has also been involved in several consultancy projects related to foundation design, pavement design projects, and slope stability, around India and Malaysia. He has also worked on several funded research projects.

Currently, he has been awarded with a prestigious funded research project on sustainable foundation systems in Sabkha soils, in the Kingdom Saudi Arabia. He has been a life member of various national and international organizations. He has organized several conferences and workshops, served as international academic advisor of universities, member of accreditation committees, and board member as well as head of many academic and administrative committees.”