The structural integrity of buried pipelines is threatened by the effects of Permanent Ground Deformation (PGD), resulting from seismic-induced landslides and lateral spreading due to liquefaction, requiring accurate analysis of the system performance. Analytical fragility functions allow us to estimate the likelihood of seismic damage along the pipeline, supporting design engineers and network operators in prioritizing resource allocation for mitigative or remedial measures in spatially distributed lifeline systems. To efficiently and accurately evaluate the seismic fragility of a buried operating steel pipeline under longitudinal PGD, this study develops a new analytical model, accounting for the asymmetric pipeline behavior in tension and compression under varying operational loads. This validated model is further implemented within a fragility function calculation framework based on the Monte Carlo Simulation (MCS), allowing us to efficiently assess the probability of the pipeline exceeding the performance limit states, conditioned to the PGD demand. The evaluated fragility surfaces showed that the probability of the pipeline exceeding the performance criteria increases for larger soil displacements and lengths, as well as cover depths, because of the greater mobilized soil reaction counteracting the pipeline deformation. The performed Global Sensitivity Analysis (GSA) highlighted the influence of the PGD and soil-pipeline interaction parameters, as well as the effect of the service loads on structural performance, requiring proper consideration in pipeline system modeling and design. Overall, the proposed analytical fragility function calculation framework provides a useful methodology for effectively assessing the performance of operating pipelines under longitudinal PGD, quantifying the effect of the uncertain parameters impacting system response.

This study investigates the ground and structural response of adjacent raft foundations induced by largescale surcharge by ore in soft soil areas through a 130g centrifuge modeling test with an innovative layered loading device. The prototype of the test is a coastal iron ore yard with a natural foundation of deep soft soil. Therefore, it is necessary to adopt some measures to reduce the influence of the large-scale surcharge on the adjacent raft foundation, such as installing stone columns for foundation treatment. Under an acceleration of 130 g, the model conducts similar simulations of iron ore, stone columns, and raft foundation structures. The tested soil mass has dimensions of 900 mm x 700 mm x 300 mm (length x width x depth), which is remodeled from the soil extracted from the drilling holes. The test conditions are consistent with the actual engineering conditions and the effects of four-level loading conditions on the composite foundation of stone columns, unreinforced zone, and raft foundations are studied. An automatic layer-by-layer loading device was innovatively developed to simulate the loading process of actual engineering more realistically. The composite foundation of stone columns had a large settlement after the loading, forming an obvious settlement trough and causing the surface of the unreinforced zone to rise. The 12 m surcharge loading causes a horizontal displacement of 13.19 cm and a vertical settlement of 1.37 m in the raft foundation. The stone columns located on both sides of the unreinforced zone suffered significant shear damage at the sand-mud interface. Due to the reinforcement effect of stone columns, the sand layer below the top of the stone columns moves less. Meanwhile, the horizontal earth pressure in the raft foundation zone increases slowly. The stone columns will form new drainage channels and accelerate the dissipation of excess pore pressure. (c) 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

Various geological disasters, such as landslides and ground movements, occur annually in Srimulyo Village, Malang District, with varying levels of damage. Ground movements can affect structures built above, causing sinking, cracking, and collapse. Research into landslides and ground movements triggered by vibrations is generally conducted using the microtremor method, which has proven effective. This study uses the microtremor method to map the soil condition that is potentially prone to movement or landslides based on the observed soil vulnerability index. Data was collected using a TDL 303s Digital Portable Seismograph instrument; the measurement points were established in the form of a grid distributed across the research area, with a recording duration of approximately 45 minutes at each point. The analysis technique utilizes the Horizontal Vertical Spectrum Ratio (HVSR) based on the Fast Fourier Transform (FFT) principle. The study's results found that the research location's seismic vulnerability index varies between 6.5 and 16.5. Areas with high seismic vulnerability index values, specifically those with Kg>11.5, are scattered on the west, south, and southeast sides of the research location. Based on field observations, these areas are dominated by relatively thick sediment layers, leading to lower dominant frequency values and higher amplification values; consequently, the seismic vulnerability index in the southern region is also high.

Kerb is an integral part of the roadway that provides structural support and facilitates drainage. When constructed over expansive soils, they face additional tensile stresses due to swelling and shrinkage caused by seasonal moisture variations. Tree roots can also exert additional tensile stresses that need to be absorbed by the kerb. Due to the relatively low deformation tolerance of concrete, premature failures are common. This study, a rigorous laboratory investigation, evaluates the effect of adding tyre-derived aggregate (TDA) and recycled polypropylene fibre on tensile strength, deformation tolerance, flexural toughness and impact resistance of concrete for potential use in road kerb construction. The effect of replacing natural coarse aggregates with recycled concrete aggregates has also been investigated. It has shown that TDA can improve deflection tolerance and polypropylene fibres can help resist larger tensile stresses. 5 % rubber with 0.66 % polypropylene fibres could be used as effective solutions in areas prone to expansive soil movement and tree root migrations.