NextGen Geotechnics

Accurately predicting time-dependent volume change in shrink–swell soils is critical for the design and forensic evaluation of shallow foundations and pavements. This talk presented an improved mechanistic–empirical framework for estimating soil volume change under seasonally varying climatic conditions.

Building on prior models by Lytton et al. (2005), Vann and Houston (2021), and Olaiz et al. (2021), the framework incorporates updated representations of short-term climate variability. Predictions were demonstrated using data from the AASHTO Long-Term Pavement Performance Seasonal Monitoring Program in north Texas and compared against field measurements, showing promising agreement. The framework is adaptable worldwide with appropriate local calibration.

The engineering behaviour of weathered deposits of off-specification fly ash produced through coal combustion for power generation.

The talk addressed reclamation and beneficial use of high organic content and ponded ash as a supplementary cementitious material in concrete, against the backdrop of recent market shortages. Trends in chemical, morphological, and mechanical properties were analysed as a function of storage conditions, with recommendations for field application in construction materials.

The development and field deployment of a bender element shear wave transducer that assesses the in-situ modulus of constructed base and subbase layers through elastic wave velocity measurements.

Dr. Tutumluer discussed instrumentation procedures and the refinement of bender element field sensors across several full-scale pavement test sections:

The session highlighted how these measurements reveal layer modulus evolution during construction, including confinement effects and locked-in residual stress development in aggregate layers.

• Smart Runway airport pavement section, Hill Air Force Base, Utah
• FAA National Airport Pavement Test Facility, New Jersey
• FHWA highway pavement test sections, Virginia

The opening session of the series, on the flow behaviour of biomass particles and what granular mechanics contributes to alternative energy systems.

NextGen Geotechnics focuses on emerging research, innovative methods, and sustainable practices shaping the future of geotechnical and geoenvironmental engineering.