A research study submitted in partial fulfillment of the requirements for the degree of Master of Engineering (Professional) in Geotechnical and Earth Resources Engineering with specialization in Geotechnical Engineering & Management

Research studies project report (M. Eng.) - Asian Institute of Technology, 2013

Control ground movement around deep excavations is important problem in crowded city to decrease its influence to adjacent buildings. Thus, a study of characteristics of ground movement in deep excavation and its effect on adjacent structures are important to predict degree of magnitude and pattern ground movement as well as damages of adjacent buildings near excavations.Measurement data of 10 braced excavations in urban area of Ho Chi Minh City using concrete diaphragm walwere assessed and generalized. These excavations for high rise building basements were made mainly in medium dense sands at depth between 7.8m and 25.5m. Maximum normalized lateral wall movement (({uF064}Hmax/H) was 0.88%. In braced mode, almost ({uF064}Hmax/H) was equal or lower0.2%, it is similar with observes of Clough and O{u2019}Rourke (1990). Besides, normalized lateral wall movement shows a trend of an increase in wall movement with decrease in system stiffness as defined by Clough et al (1989).An increase modulus value of sand layers by about 3 times original value ( E{u2019}= 3000-6000N for back analysis instead of E{u2019} = 1000-2000N usually) was demanded for a better predict. And workmanship factor in strut installation is important to effect to lateral wall movements.The influence zone of braced excavations using diaphragm wall in sand to adjacent buildings can reach to 2H form diaphragm walls ( H depth of excavation) and limit in 1H if drawdown can be control.