Study of the Factors Affecting the Quality and Safety of Deep Excavations in Urban Areas of Casablanca-Settat Province-Morocco

Abstract

Understanding the project environment is essential in managing the works and controlling the risks associated with deep excavations in urban areas. The study was carried out on 33 risks related to the project site (SR) and the company (CR). The projects concerned are located in the Casablanca region. A structured survey questionnaire was sent to 100 project managers, researchers, and construction management experts to attract relevant data, which resulted in a relatively high response rate of 54%. This paper applies the principal component analysis (PCA) method to reduce the original data variables and identify risk factors associated with deep excavations. Spearman rank correlation tests show a good consensus among respondents to corroborate the results further. The PCA results in four principal factors (SR) accounting for 68% of the variance explained. Site geology, geotechnics, and hydrogeology account for 32% of the environmental and social impacts of excavation (17%), natural hazards (10%), and proximity to existing structures (8%). Moreover, four main factors (CR) explain about 72% of all the factors analyzed; non-security of the works (32%), non-quality of project staff (18%), project cost overrun (14%), and non-quality of excavation works (9%). These results are useful for critical thinking in planning excavation projects in urban areas. This study provides the urban development community with valuable information to reassess risk factors and realign project management strategies to ensure the quality and safety of deep excavations.