Eliot Sinclair developed a new way to display the information obtained by a Topographical Survey for overhanging retaining walls. The results of these surveys are used for plotting cross sections to develop a repair strategy for a retaining wall.
Description of problem faced/task undertaken
Overhanging features are difficult to capture and represent on two dimensional plans. Traditional terrain modelling applications are often limited in their ability to correctly represent overhanging faces. New techniques were required to allow cross sections or volumes to be calculated. Innovative methodology to survey the retaining wall and generate terrain models had to be developed.
How the problem was solved
Field techniques were adopted to survey every overhang individually and represent the retaining wall in full detail. 3D laser scanning considerably reduces the field work which equates to a savings in staff time and costs to the client.
Processing techniques were devised to generate 3D faces of the retaining wall. Automated macros simplified the process and generated triangulations (DTM) for individual wall parts. These can be profiled as cross sections and further manipulated for volume calculations.
Retaining wall volume calculation was developed based on the data produced by the above procedures. Additional visualisation tools assist with communicating results to clients in a clear effective manner.