A project was underway at the University of Texas at Arlington in order to develop a strategy to monitor and evaluate the crack progression over time, determine the possible factors and assess deformation of distressed CIP cantilever retaining wall. The project has three phases, field observation, FE Modeling and retrofitting options if needed. The first phase involved observation, field monitoring and data analysis of the CIP cantilever retaining wall. This was done by using Trimble SX10 scanning the total station, installing crack meters and stainless-steel discs. The second phase involved modelling by using nonlinear finite element ABAQUS software. The impact parameters that will be taken into accounts are spacing of steel reinforcement, concrete compressive strength, foundation stiffness, backfilling material, wall dimensions, and the drainage system. The third phase will be retrofitting options if needed, based on the results of field monitoring data and ABAQUS finite element simulation. 

The following techniques and tests were performed:

3D Robotic Laser “SX 10” Scanner: This machine will be used to record the movement on a timely basis of the CIP cantilevered retaining wall. It will be achieved through installing control points and back-sights on fixed objects for the instrument setup, and targets on the critical panels.

Ground Penetrating Radar (GPR): A real-time non-destructive testing (NDT) technique that uses high-frequency radio waves, yielding data with very high resolution in a short amount of time. The test was performed to accurately detect and mark the steel reinforcement location.

Concrete Core Test: The standard test method was performed to determine the in-place concrete strength of the retaining wall.

Resistivity imaging (RI): A non-destructive, fast, and cost-effective method of site investigation and soil characterization. The primary objective in performing the test was to obtain qualitative information and to detect the presence of water zones behind the wall panels.

Backfill Soil Testing: Boreholes were drilled in the backfill soil behind the CIP retaining walls. Following that, the soil tests were conducted on the samples obtained to find the mechanical properties of the soil.

Compressometer: Used to measure compressive strain produced by loading forced in the axial direction of cylinder concrete test.