Characterization of Paving Blocks for Road Pavement: Case of the Urban High-Intensity Manpower Program in Senegal     

Mababa Diagne 《Geotechnical and Geological Engineering》2012,30(6):1303-1309

A large network of paving blocks has been initiated in some districts of the region of Dakar (Senegal) within the framework of the Urban Program of High Intensity Manpower (PUHIMO). The purpose of this study is to explore the process of production of paving blocks to be used for roads and sidewalks. The study also seeks to investigate the materials used for the formulation of hydraulic concrete for the manufacturing of paving blocks that are H-shaped. The blocks made are 20?×?10?×?6?cm³ of size. The originality of this paper is the complete substitution of crushed basaltic sand by the fines of alumina phosphate that are stored for a long time over large areas. These fines particles of phosphate are generated by the physical processing (crushing, transportation and screening) of the raw alumina phosphate material. This paper deals with how to make good paving blocks out of crushed basaltic sand on the one hand and on the other hand with how to substitute basaltic sand for fines of alumina phosphate as waste for their recycling. The finished products are tested, for their resistance to splitting rupture, for their abrasion and for their water content, to see their compliance with the European standard EN 1338, which defines, according to the results obtained, their use or not in road pavement and in sidewalks. The standard values must be below 23?mm for abrasion, 3.6?MPa for the tensile rupture strength and 6?% for the percentage of total water content. Average abrasion values of 20.71 and 22.67?mm, 5 and 3.46?MPa of splitting rupture strength, 5.26 and 7.73?% of average water content are obtained in paving blocks made respectively out of crushed basaltic sand and out of fines of alumina phosphate. These results obtained testify good physical and mechanical characteristics of the paving locks made out of fines of alumina phosphate compared to the standard, if tolerance values are taken into account.  相似文献   

Multisource Data Integration for Fire Risk Management: The Local Test of a Global Approach     

Diagne  M. Drame  M. Ferrao  C. Marchetti  P. G. Pinto  S. Rivolta  G. 《Geoscience and Remote Sensing Letters, IEEE》2010,7(1):93-97

In this letter, we propose an algorithm to detect the presence of forest fires using data from both geostationary and polar-orbiting satellites. The very frequent acquisitions of the Spinning Enhanced Visible and Infrared Imager radiometer placed onboard the Meteosat Second Generation-9 satellite are used as main source for the algorithm, while the MEdium Resolution Imaging Spectrometer global vegetation index and the Advanced Along-Track Scanning Radiometer measurements are used to enhance the reliability of the detection. The problem is approached in a “global” way, providing the basis for an automated system that is not dependent on the local area properties. In cooperation with the Centre de Suivi Écologique (Dakar, Senegal), the proposed algorithm was implemented in a “Multisource Fire Risk Management System” for the Senegal area, as briefly described in this letter. A field campaign of one week was carried out in order to perform a validation of the system's detections, showing a good agreement with the fire coordinates measured on the ground. Furthermore, a consistency check was performed using data from the Moderate Resolution Imaging Spectroradiometer (MODIS) Rapid Response System, showing that more than 76% of high-confidence MODIS events are detected by the algorithm.   相似文献