JK,W,EurthSci.,\·01.6.",,47·77 (14 13 A.II./1993A.I).)
Ground Conditions in Al-Madinah Al-Munawarah, Saudi Arabia
MOHAMMAD IBRAHIM MATSAH*
and
DELWARHOSSAINH. , Department of Structural Geology and Remote Sensing,
" < Departm ent of Engineering Geology, Faculty of Earth Sciences,
King A bdu laziz Universit y , Ieddah , Saudi Arabia
AUSTRA C1. TheSaudi Ara bianCityofAI-M ad ina h issituatedinadepos- itionalbasinsurround edbyla vaplateau s and hillswithin thewesternpari of the Ara bia nShield. Within a maximum depthof 45rn,the su b-soil in AI- Madinahconsists of ninesoiltypes(one"fill",six natural co hes ive and two cohesio nle ss) and three ro cktypes. The cohe sive soilsvaryfrom highl y co mpre ssible organicclay andso ftco mp ress ible/s wellinggrey-gree n clay10 hard claywhilethe cohesionlesssoils are of mediumtover yden se rela tive density.Thero ck s va ry from wea klimest on etomassivegabb row,The"fill"
andso me of the othe rsoils occurat the topwhiletherocks occu r eitherat depth orasisolated hilly outcrop s.
Poor or pro blcrn utic ground cond itio ns arc encount ered down to a maximum depthof15m in someareastothe so uth.eastand north-ea st of theProphet's Mosquedueto thepres en ce of weak soilswith highcompres- sibility and/orswellpotent ial.
Prot ective measur es for foundati on con crete and reinforcement are nece ssar ydue to aggressivegro u nd conditions.Ground watercont ro l mea- suresare generall ynot requiredforusual const ructio ns .
l. Introduction
The holy city of AI-Madinah AI-Munawarah is located in Western Saudi Arabia. The recent oil-boom initiated a large volume of development work in it. The site investi- gation reports of so me of the recent major projects of AI-Mad inah like the large-scale expansion o f the Prophet's Holy Mosque and The Ring Roads contain a large volume of geotechn ical data about the AI-M adinah sub- soil which has little be en studied ex- cept for Erol et al. (1981) , Dhowian et al . (1990) (on the swe lling potential of two AI- Madinah clays) , Sabbagh and Abuzaid (1991) (on reduction of swe lling pressure of a
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