SPIN ESR 4.2: Nonlinear seismology meets structural health monitoring

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Host institution: University of Hamburg (UHH)

Supervisors:

main supervisor:	Céline Hadziioannou (University of Hamburg, D)
co-supervisors:	Andrew Curtis (University of Edinburgh, UK)
	Ernst Niederleithinger (Federal Institute for Materials Research and Testing, BAM, D)

This position is filled

Project description

Many bridges, dams, buildings and other structures in Europe have reached an age where deterioration and limited load capacity become a serious problem. Methods of nondestructive testing (NDT) and structural health monitoring (SHM) are important to assess the status and capacity of structures.
In this PhD project, we transfer knowledge between civil engineering and seismology. Our goal is to evaluate and monitor changes of mechanical properties of materials, which are associated with long-term damage development in civil structures. To do this, we will apply seismic wavefield-based techniques to detect and quantify changes in propagation velocity and scattering properties. We will investigate the optimal way to measure self-healing timescales after reversible damage is induced on a concrete test structure.
In parallel, we will assess the sensitivity of velocity changes and of healing timescales to environmental conditions (temperature, pore fluid content, etc). Through this, we investigate whether it is possible to distiguish these effects from the underlying, long-term changes in internal strength of the structure.
This part of the project will benefit from close interactions with other projects in the SPIN network, as well as with other PhD candidates within SPIN, who will evaluate array sensitivity towards transient changes.

Throughout the investigations described above, we will evaluate which benefits to the monitoring methods can be provided by the use of novel sensors (e.g. rotational, strain/DAS). We will design and perform experiments on concrete test structures at BAM (Federal Institute for Materials Research and Testing, Berlin), in close collaboration with the scientists there. Using an optimized sensor deployment based on the work by a different PhD candidate, the test structure, will be instrumented with complementary sensors and both active and passive measurements will be performed.
The long-term goal of this project is to develop seismic wavefield-based methodologies for detecting a monitoring damage and deterioration of dams, wind turbines, high-rise buildings, and other structures which are constantly under stress.