The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
the measurement with no or little sample preparation, making 
dense sampling easy as compared with the requirement of large 
volume of samples to perform engineering tests, and the tedious 
and time consuming testing procedures using conventional 
techniques. Hence, it can be of great benefit in avoiding under 
sampling of sites. The approach can be useful in getting an 
estimate of engineering parameters of expansive soils, in early 
stages of construction projects where site information on 
geotechnical behaviour of soils is limited. Therefore, 
spectroscopy can play an important role particularly in 
identifying sites that might need due attention and further 
detailed geotechnical assessment with respect to the presence of 
potentially expansive soils. 
ACKNOWLEDGEMENT 
The authors are greatly indebted to Mr. Bekele Negussie of the 
Ethiopian Roads Authority (ERA) for facilitating field work 
data collection in Addis Ababa. We would also like to 
acknowledge and Mr. Hailu Chekun and all the staff members 
of the Alemgena Soil Testing Centre of ERA for provision of 
laboratory facility and help in determining engineering 
parameters of soils. 
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