Missouri University of Science and Technology Scholars' Mine International Conference on Case Histories in (1988) - Second International Conference on Geotechnical Engineering Case Histories in Geotechnical Engineering 02 Jun 1988, 10:30 am - 3:00 pm Geotechnical Characterization of Subsoil Deposits at Cairo Mohamed A. El-Sohby University of Al-Azhar, Cairo, Egypt S. Ossama Mazen General Organization for Housing, Building and Planning Research, Cairo, Egypt Follow this and additional works at: https://scholarsmine.mst.edu/icchge Part of the Geotechnical Engineering Commons Recommended Citation El-Sohby, Mohamed A. and Mazen, S. Ossama, "Geotechnical Characterization of Subsoil Deposits at Cairo" (1988). International Conference on Case Histories in Geotechnical Engineering. 17. https://scholarsmine.mst.edu/icchge/2icchge/2icchge-session2/17 This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License. This Article - Conference proceedings is brought to you for free and open access by Scholars' Mine. It has been accepted for inclusion in International Conference on Case Histories in Geotechnical Engineering by an authorized administrator of Scholars' Mine. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. Proceedings: Second International Conference on Case Histories in Geotechnical Engineering, June 1-5, 1988, St. Louis, Mo., Paper No. 2.56 Geotechnical Characterization of Subsoil Deposits at Cairo Mohamed A. EI-Sohby S. Ossama Mazen Professor, Civil Engineering Department, University of Ai-Azhar, Senior Researcher, General Organization for Housing, Building and Madinet Nasr, Cairo, Egypt Planning Research, Dokki, Cairo, Egypt SYNOPSIS: As a result of considering the historical aspects in Cairo subsoil at different stages of its development, soil deposits in the alluvial plain in Cairo area could be identified and classified on their origin into limited number of major types. Their distribution could be prod­ uced on maps on which classes of engineering significance are recognized. The boundaries between map units have been drawn separating areas of equal origin and characteristics. Verification of soil profile from field investigation indicated complete agreement with the previous characteriza­ tion based on theoretical considerations. INTRODUCTIOH land use inefficiencies. Most good building sites have already been exploited and more use Cairo is one of the few great symbolic cities will have to be made of sites with less favour­ with their extended history and current vital­ able conditions. Many-structures will have to ity. In all probabilities, the earliest go underground and installation of services be­ developgent of civilization had took place neath existing building will necessitate tunnel­ near to this strategic site and, as a capital ling. of Egypt, ~emphis of the Pharaoh, in the vicinity of Cairo antedates almost every other As a result, a great volume of routine investig­ human conglomerate larger than a village. The ation has been carried out and still going on by parade of historical monuments preserved in several public bodies, private companies and and around Cairo span a period of more than consultants for different important projects five thousand years and express the entire such as Cairo Underground Metro, and Greater civilization of the country. There is no one Cairo Sewerage Plan. epoch of history which had not left within it numerous and precious traces. Because boring records and reports for each site or project are generally very detailed and no The wonder of Egypt is not only in its history or a little exchange of information has been but also in its site. At the meeting point of experienced, soil deposits in Cairo give the the three big continents· of the ancient world, impression that they are of extreme complexity Europe, Asia and Africa lies Egypt. Here also and countless variety. Therefore duplication of two \'/aterways meets, important in history and effort is likely to be extensive. commerce of the world: The Mediterranean and the Red Sea. The former brings Egypt in direct The primary aim of the present work is to improve contact with the West, while the latter joints that situation by making clear the ground forma­ it with the Far East. And just as Egypt stands tion in Cairo area. This would develop the astride East and West, so, Cairo, its capital knowledge of subsoil conditions, help in recogn­ stands astride Egypt linking, as well as domi­ ising potential soil problems; and guide in good nating, the two subregions - Upper Egypt to planning of site investigation work. Thus the its South and Lower Egypt to its North. Its time and effort donated to field work and labor­ dominance is challenged only by The Nile, the atory testing can be greatly reduced. river t~at bisects both Cairo and the nation but paradoxically unifies as it divides. The implicit goal is to extract a form or a pat­ tern from what appears to be capricious disorde~ Its location is 30° 4' North latitude and 31° However, if order is to be found,more than the 17' cast longitude 20 kilometers to the South traditional methods must be employed to uncover of the point where the Nile divides into the the hidden framework. Rosetta on Dametta branches. To the East, Cairo reaches the Mukattam Hills, announcing Geology and history, envisaged to be of relev­ the Eastern Desert, in the West it crosses the ance of the present work, were used to separate Nile into Giza to the Western Desert which the accidental from the essential and to trace eventually extends to the Libyan Desert. the chains that binds present with past andlinks part with whole. This to uncover the orderly Cairo today, home for more than 10 million patterns and sequences in Cairo's growth and inhabitants, presents, to the geotechnical development that yielded the present soil forma­ engineer, primary problems and enormous chal­ tions and have given rise to fts particular lenge. It is a city with a pressing problem of characteristics. 321 Second International Conference on Case Histories in Geotechnical Engineering Missouri University of Science and Technology http://ICCHGE1984-2013.mst.edu GEOi~ORPHOLOGY GEOLOGICAL ASPECTS Egypt may be divided into four geographical re­ The geological formations at the site of Cairo gions: The Eastern Desert, The West~rn_Desert, have the features of hill-slopes which appear as The Nile River and Delta, and the S1na1 Desert. wall bordering the valley and filled with depos­ Cairo covers portions of the first three regions its These deposits which comprise the valley (see Fig. 1). fili within the area of the bordering E?cene limestone are fluviatile sediments rang1ng from Pliocene to Recent. The geology of Cairo has been studied intensively by many ~esearchers, as far as the older forma­ tion are concerned (Beadnell, 1902, Barron, 190?; Cuvilier, 1924; Hume, 1925; Lawson, 1927; Shukr1, 1953; Attia, 1954; Said and Youssri, 1964; Youssef, 1968· Abu Al-Izz, 1971; Said, 1981). However, the fluviatile sediments of the Nile Valley have been treated lightly. The most thorough treat­ ment of the latter deposits was done by El-Sohby and Mazen (1985). Their study depen~ed on infor­ mation received from boreholes, deta1led recor?s, wells and excavations that penetrate the format1ons. According to El-Sohby and Mazen (19~5), the !luv­ iatile sediments comprises of alluv1um and dlluv­ ium. Alluvium are soil deposits laid down in recent times by flood waters while diluvium are deltaic soil deposits formed at earlier stages of river developments. HISTORICAL ASPECTS Because Cairo is a very old city, historical ele­ ments dictated the city pattern of growth and they are the key to the pattern of formation of deposits in alluvial plain. Therefore, in the following, tht telescopic lense of history is used in studying the Cairo subsoil at different stages of its development. Three main elements are considered in the study; they are: 1) the geographic features of the site; 2) the River Nile and its changes; 3) Man's occupation of the area. Although the history of Cairo spans more than 7000 y~ars,. the more recent history with Fig. 1 Greater Cairo Area Topographic Features & impact upon subsoil and relevance in explain~ng soil conditions can be traced from the foundag The Nile is a perennial stream which flows South AD 641 of Al-Fustat which lies towards the Sou­ to North and divides Egypt into the Eastern and thern boundary of the existing city. Western Deserts. The relatively flat alluvial plain and the gently sloping terraces to the The references consulted for historical informa­ higher desert areas form the Nile Valley. At tion were numerous. However, we relied heavily the site of Cairo the Nile Valley is 10 to 15 on three notable original sources. They are: kilometers wide. 1) the Khittat of Al-Maqrizi; 2) Description de l'Egypt of the French Expedition; and 3) Al­ Throug~ Cairo area, the Nile passes by the high Khittat Al-Tawfiqiah Al-Gadida by Mubarak. Mukattam Plateau of the Eastern Desert. On the Western side, beyond the valley, the cliffs are Gedgraphic Features in the Seventh Century lower and form the Pyramids Plateau. Just down­ stream from Cairo, the valley widens and forms At the site of Cairo, the boundary of the Nile a large delta tributary to tne Mediterranean sea. flood plain is fixed by two sudden escarpments Two branches of the Nile meander through the of the Muqattam Hills on the East and the delta area; the western branch enters· the Medi­ Pyramids plateau on the West. The ridge which terranean Sea at Rosetta and the eastern braoch divides valley from desert on the Eastern side at Damietta. is nearest to the river at the site of Qasr Al­ Shama before it pivots Northeast until it dis­ The general slope of the Nile flood plain is to appears when the valley opens at the site of Al­ the North, Elevations along the river flood • Fustat;·then it becoming increasingly broader to plain range, from 22m at the South· end of Ca1ro the North.