The Traffic Speed Deflectometer (TSD) is a mobile vehicle that measures deflection slopes. Deflection slopes have been utilised in previous studies to backcalculate pavement layers' moduli. However, the nonlinear stress-dependency and cross-anisotropy of unbound granular materials and fine-grained soils were overlooked in those studies. Utilising the Finite Element Method (FEM) based on static analysis in this study to evaluate a three-layered flexible pavement system with specific material properties and layer thicknesses revealed that neglecting the nonlinear stress-dependency of base and subgrade layers underestimated the permanent deformation life of the backcalculated pavement by more than 45%. Neglecting the cross-anisotropy of the base layer with the design anisotropy ratio of 0.5 increased the backcalculated Asphalt Concrete (AC) modulus by more than 21%, increased the estimated permanent deformation life of the pavement by more than 160%, and decreased the backcalculated base modulus by around 28%. Neglecting the cross-anisotropy of the subgrade with the design anisotropy ratio of 0.5 almost increased the estimated permanent deformation life of the pavement by 15%. The results underscore the necessity to consider the nonlinear stress-dependency and cross-anisotropy of unbound granular materials and fine-grained soils in backcalculating pavement layers' moduli from TSD deflection slopes.

Evaluating the mechanical properties of deep soil mixing (DSM) requires destructive borehole coring because they are mainly situated underground. Although surface wave method offers potential for quality assurance, its complexity arises from multi-mode phenomena and the need to re-evaluate inversion results, often necessitating manual interpretation. This paper presents a data-driven surface wave framework to retrieve field DSM profile Vs over time, incorporating a mode-free forward operator and the Monte Carlo Tree Search (MCTS) inversion. Validations using synthetic data affirmed the framework's accuracy and efficiency in tracking subsurface shear wave velocity. In a real-world DSM site, the proposed method successfully captures the mechanical properties evolution across two DSM layers over the curing period, aligning well with site investigations and borehole coring. This pioneering monitoring framework integrates geotechnical engineering with geophysics expertise, underscoring the value of non-destructive seismic methods for measuring subsurface property evolution.

Most earthen historical buildings have been abandoned for decades, exposed to the weathering and the passage of time. In Mexico, the low status of earthen constructions has increased these deterioration processes, resulting into the risk of disappearance of this significant architectural heritage. Historical adobes from monumental buildings in the State of Michoacan were sampled and collected in the localities of La Huacana (H) and Santa Cruz de Morelos (SC). The specimens were characterized in the materials laboratory, assessing their physical-chemical, mechanical and durability properties. An interdisciplinary methodology was designed through institutional cooperation and the application of different test methods. The adobes showed totally different compositions and proportions, and stabilizers like vegetal fibers, nevertheless, the mechanical performance of both samples was very similar, achieving respectable values in the context of historical adobe structures. Several correlations were found through the analyses: the physical properties like the density, the color or the electrical resistivity were related with the mechanical and durability ones; the non-destructive testing (NDT) allowed to calculate the dynamic elasticity modulus and infer the mechanical behavior; the chemical characterization enabled to obtain the elemental and mineralogical composition; and the Atterberg limits gave the soil classification. The research showed the broad diversity of earthen solutions and demonstrated how the granulometry is not a limitation to the adobe production, since the local soils can achieve similar mechanical and durability behaviors. Furthermore, H presented very different composition than the guidelines for earthen construction; nevertheless, the samples showed better durability performance and lower capillarity absorption rates. It is hoped that the results obtained with this research can help the further development of the earthen materials characterization and the decision-making process for the restoration and conservation of historical and vernacular constructions.

Seepage cut-off walls are common seepage mitigation measures in dikes to minimize seawater ingress. These cut-off walls are usually made of cement-bentonite (CB). The quality of this CB wall is critically important. Non-destructive testing would ensure quality control/assessment without damaging the wall's integrity. One such non-destructive technique is the measurement of electrical resistivity. Correlations can be established between electrical resistivity, strength, and permeability of CB mixes. Continuous monitoring of electrical resistivity across the CB wall would enable early detection of its properties instead of waiting for coring of samples after 14, 28, or 91 days of curing, which would introduce discontinuities in the wall. For in situ electrical resistivity measurement, electrodes of finite size are buried in an infinite soil medium, where As, the area of soil mass is much larger than Ae, the area of electrode. This is very different from laboratory measurement, of which As = Ae. Thus, the effect of boundary on these two situations is very different, and the correlation between resistivity and unconfined compressive strength, as well as between resistivity and permeability, established in a laboratory setup may not be suitable for use in in situ measurement condition. Hence, this paper aims to systematically study the impact of boundary on the electrical resistivity of CB mix. Consistent CB mix placed in boxes of different heights and widths (thus different values of As) was designed to study the boundary effect, with area of electrodes (Ae) kept constant. It was found that the electrical resistivity value increases with reducing As/Ae value, and As/Ae has to be greater than 25 to negate the effects of boundary on electrical resistivity. In addition, there is an issue on the direction of resistivity measurement. The in situ resistivity measurements were more conveniently carried out horizontally in an infinite soil medium, while the laboratory cored samples were normally measured in vertical direction. Thus, there is a need to study the anisotropy effect on electrical resistivity value of CB mix.