TITLE:
Design of Foundations Built on a Shallow Depth (Less than 4 m) of Egyptian Macro-Porous Collapsible Soils
AUTHORS:
Tahar Ayadat, Adel Hanna
KEYWORDS:
Collapsible Soils; Design Method; Foundations; Shallow Depth; Settlement
JOURNAL NAME:
Open Journal of Geology,
Vol.3 No.3,
July
11,
2013
ABSTRACT: It is nowadays well reported that
collapsible soils spread in many countries, including United States, Russia,
China, South America (e.g. Brazil), South and North Africa (e.g. Egypt,
Algeria), Middle East (e.g. Saudi Arabia) and many countries in Eastern Europe.
In general, collapsible soils are located in arid and semi-arid regions around
the world. This special type of soil is characterized by abrupt reduction in
strength, excessive and sudden settlement when it becomes wet leading to
failure of the structure. Construction on such a kind of soil is one of the
prominent problems in geotechnical engineering. The main objectives of this study are reporting geological and
geotechnical zonation maps for potentially collapsible soils in inhabited areas
in Egypt. Furthermore, a design
technique for foundations built on a shallow depth of Egyptian macro-porous
collapsible soils (less than 4 m) is developed. The design method includes a
design chart for soil collapse field classification in terms of the most
governing parameters, a method for foundation settlement estimation based on a
correlation between the wetting-induced collapse strain and the applied
pressure, and a design practice to guide practicing engineers to select the
appropriate foundation system to construct on such soil with a great degree of
confidence and safety.