Measuring construction and post-construction deformations of mechanically-stabilized earth walls using terrestrial laser scanning

点击翻译按钮获取中文摘要

TREK Geotechnical Inc. is a geotechnical consulting firm in Winnipeg, Manitoba that specializes in the design of foundations and earth structures. Their current project, the McOrmand-College Drive Interchange in Saskatoon, Saskatchewan uses Mechanically-Stabilized-Earth (MSE) retaining walls for abutments. MSE walls are cost-effective and technically-efficient because it can handle large deformations with minimal structural distress. However, deformations should be within tolerable limits and should be monitored during and after construction of the walls. Common monitoring practices, like settlement plates and total station, do not survey the entire wall, only at few discrete points. There is uncertainty about how much movements in the non-surveyed locations can occur.This research will assess the applicability of Terrestrial Laser Scanning (TLS) in surveying these MSE walls. The TLS is a non-destructive method that can complete its scanning of the entire wall in an hour's time without the need for permanent setup at site. Scanning will be done during and after construction is completed. The data from the scans will be analyzed to determine the horizontal and vertical movements from when the wall was first installed. This data will be compared to data collected from the settlement plates and total station that are surveyed at site. A numerical model will be developed to predict deformations of MSE walls. Calibration of the numerical model and laser scanner data adequacy can aid in future design, construction, and maintenance operations of MSE walls and other geotechnical infrastructure. With the increased efficiency of structure monitoring and knowledge of soil settlement behaviour, this research will help designers and contractors in reducing financial risks of schedule delays, conservatism in design, and safety risks of structure deformation exceeding tolerance limits.