Transversely isotropic rocks (TIRs) are widespread in geological formations, and understanding their mechanical behavior is crucial for geotechnical and geoengineering applications. This study presents the development of a novel analog material that reproduces the directional mechanical properties of TIRs. The material is composed of quartz sand, mica flakes, and gelatin in adjustable proportions, allowing control over strength and stiffness anisotropy. Uniaxial compressive strength (UCS) and direct shear tests were conducted to evaluate mechanical responses across different anisotropy angles. Results show that the analog material replicates key features of natural TIRs, including directional variations in strength and fracture modes. In UCS tests, the anisotropy angle (beta) governs the transition between tensile and shear failure. In direct shear tests, the orientation angle (alpha) significantly affects shear strength. Higher gelatin concentrations increase cohesion and Young's modulus without changing the internal friction angle, while mica content reduces overall strength and stiffness. Comparisons with published data on sedimentary and metamorphic rocks confirm the mechanical representativeness of the material. Its simplicity, tunability, and reproducibility make it a useful tool for scaled physical modeling of anisotropic rock behavior in the laboratory. This approach supports the experimental investigation of deformation and failure mechanisms in layered rock masses under controlled conditions.

At 4:17 am (1:17 UTC) on Feb. 6, 2023, an earthquake with Mw=7.8 struck near Pazarc & imath;k City in south-central Turkey, followed by a 7.5 Mw event about 9 h later. The subsequent earthquakes can cause severe damage which might not be the case for single earthquakes. In this study, a series of shake table tests on level ground with a sloping base model were conducted to investigate the effects of subsequent liquefactions on two 2 x 2 pile groups with a minor fixity in the caps. Adequate time intervals for complete dissipation of excess pore water pressure in the liquefiable layer were permitted at the end of each shaking. For this purpose, the free field soil and the piles were sufficiently instrumented to measure various parameters during and after the shakings. In this paper, the results of one of the shakings are reported and discussed in detail, and the results of other shakings are compared. The reported results contain time histories of acceleration, displacement, pore water pressure, bending moment, shear force, and lateral pressure on the piles. The ground settlements due to subsequent earthquakes are also measured and reported. The findings reveal that in a level ground liquefiable layer overlying a sloping base, lateral spreading may also occur and affect the piles behaviour especially in subsequent earthquakes. In addition, a practical relationship is proposed from the experimental results to estimate the residual shear strength of the liquefied soil.

This study focuses on the behaviour of buried gas pipelines subjected to surface loading. The study is oriented towards an experimental campaign carried out on small-scale pipelines, with three different wall thicknesses, both in monotonic and cyclic conditions. Pipes have been instrumented with strain gauges and inner displacement sensors, allowing to record deformations, stresses and ovalisation of the pipe, in addition to the load-settlement relationship at the soil surface. Results show that the presence of the pipe affects the global soil response (stiffness and bearing capacity). Analysis of the strain distribution and pipe deformed shape indicate that the pipe response is complex, with no symmetry along the horizontal axis, and a heart-shaped deformation pattern. The pipe rigidity affects the local behaviour at the pipe level (displacement pattern, evolution of stresses during cyclic loading and increasing lateral support). Classical pipeline design theory has been assessed based on the experimental observations, invalidating several underlying hypotheses.

Cyclic loading features in many applications. Questions important for design include: Does the monotonic capacity increase or decrease following cyclic loading? How does foundation rotation, stiffness and damping evolve? This is investigated here for suction caissons in sand, looking to applications as foundations for offshore wind turbines where changing stiffness, capacity and accumulated rotation can be critical, and soil damping is being looked at more closely. The problem is investigated experimentally through a series of single gravity monopod caisson tests in saturated sand subjected to unidirectional or multidirectional cyclic loading with between 360,000 and 106 cycles applied in each test. Results from the unidirectional tests are consistent with previous experimental studies, whilst also demonstrating the expected changes in damping ratio during cyclic loading for a monopod caisson in sand. The multidirectional tests reveal more significant and potentially important findings, particularly on the very significant increases in unloading stiffness and damping ratio associated with load direction changes.

Testing of small-scale physical models of masonry structures can be useful both to study Soil Structure Interaction problems and to provide large enough datasets to statistically validate the global level assumptions of masonry numerical models. This paper proposes the use of a sand -based Binder Jet 3D printer to manufacture 1:10 scaled physical models of masonry walls, that can be used within a centrifuge. As such printers can only print one material, mortar is emulated by controlling the micro -geometry of the printed material at the position of the joints (i.e., by printing joints). Walls were printed and tested in compression and cyclic shear under fixed -fixed conditions and constant compressive load. Different notch geometries were tried. The tested specimens were found to behave similarly in compression and shear to full scale masonry walls. A numerical model using a concrete damage plasticity model was built in Abaqus. It captured the cyclic response of the masonry walls with a reasonable accuracy. Therefore, such small-scale models can be used to expand centrifuge modeling in structural engineering.

A series of physical model tests and cyclic triaxial tests were performed on a dry sand to investigate the effects of excavating an adjacent pit on the settlement behaviour of a footing under cyclic loading. The excavation is simulated by moving a retaining wall between loading cycles in the physical model tests. The excavation induced stress disturbance on soil elements is modelled by reducing cell pressure between loading cycles in triaxial tests. The results indicate that nearby excavation leads to reduction in lateral stress in ground and therefore increases the settlement of footing in the subsequent loading cycles. However, there is no clear relationship between the settlement increment and the magnitude of wall movement, when the lateral movement of the wall is within the range of 0.1% to 0.37% of the wall height. The lateral excavation does not have great impact on the influence zone of the footings under cyclic loading. An empirical model is proposed to estimate the cyclic loading-induced strain accumulation of sand with the consideration of lateral unloading effects between loading cycles. After being validated using cyclic triaxial tests results, the proposed model is employed to predict cyclic loading-induced settlement of the footing before and after the excavation.