Bearing Capacity Map for An-Najaf and Kufa Cities Using GIS

Abstract

An-Najaf province is situated in south-western part of Iraq. It is 70 meters above the sea level in the dry desert environment. The city is considered as one of the most important cities in Iraq, facing a fast population growth and continuous development in constructions such as residential complexes, hotels, bridges and shopping malls. Soil investigation data for An-Najaf Province (An-Najaf and Kufa cities) from 464 boreholes drilled by the Na-tional Centre for Construction Laboratories & Researches (NCCLR)/Babylon laboratory were used in this research. The data were analysed and possessed using Excel program then represented on the Geographical Information System (GIS) program by Inverse Distance Weighted (IDW) tool to create an allowable bearing capacity map for the soil at depths 0 - 2 meters. The allowable bearing capacity is one of the most important soil characteristics to be considered when making a database for An-Najaf city soil. Geographical Information System GIS program enables to create reliable database for any characteristic and it is one of the best programs to produce an accurate map and allow ease in dealing with it. Those maps cover all the studied areas and by using contour lines, approximate values for no-data areas can be obtained. The results show that the allowable bearing capacity range is 5 - 20 Ton/m 2 for both An-Najaf and Kufa cities. Kufa city has the range 5 - 9 Ton/m 2 . An-Najaf city has the range 7 - 18 at the center, 8 - 10 Ton/m 2 at the north eastern part, 7 - 14 Ton/m 2 for the north western part, 6 - 12 Ton/m 2 at the south eastern and 12 - 19 Ton/m 2 at the south western.