The application of the FBG sensors is considered for two geotechnical problems, namely, pile jacking and a ‘retaining wall’ adjacent to a tunnel (acting as a protective wall to prevent an adjacent structure from tunnelling induced ground movement). The precision and reliability of the FBG sensors are demonstrated using verification tests. The effect of thermal expansion/contraction of the materials (including both the fibre and structures) is considered and assessed. This paper gives an overview of recently developed installation and calibration procedures for FBG sensors within buried centrifuge model structures. FBG sensors have several advantages for centrifuge testing, in particular their small size and minimal self-weight. This paper presents a novel application of fibre Bragg grating (FBG) sensors for strain measurement within geotechnical centrifuge tests. One challenge for geotechnical centrifuge testing of soil-structure interaction problems is the reliable measurement of induced structural strains/forces. Data from the instrumented walls and piles are used to explain the dominant mechanisms at play and investigate how the load is redistributed within the piles. Compared to the ‘no-wall’ case, the ‘deep’ protective wall is shown to significantly reduce uneven pile settlements, structural distortions, and load transfer (through the building) between piles the ‘shallow’ wall is shown to have little benefit. Two protective walls with different embedded depths are considered: a ‘shallow’ wall with its toe at the tunnel axis depth and a ‘deep’ wall with its toe below the tunnel invert. In this paper, results from four hybrid geotechnical centrifuge tests (where data are coupled between the centrifuge and numerical models) are used to quantify the effect of protective walls on reducing the impact of tunnelling on an adjacent framed building with four piles. In practice, to protect structures from tunnelling-induced damage, a stiff protective wall can be constructed between the tunnel and the adjacent piled structure. Tunnel excavation in urban areas causes ground movements that could damage existing nearby piled structures. These data provide additional insights to complement and extend current understanding of the complex soil-pile interactions taking place. Numerical analysis results are used to explore the effect of tunnelling on pile settlements and the development of radial stresses around piles, as well as the stress paths at the soil-pile interface. Despite some discrepancies between numerical and experimental results, in particular related to limitations of the adopted soil-pile interface model, results from the numerical simulations are shown to broadly agree with the centrifuge test data. An advanced hypoplastic constitutive model was adopted for the soil and, to enable appropriate comparison of numerical and experimental results, the conditions within the centrifuge tests were replicated numerically. This paper extends the experimental data set with a finite element numerical analysis of the problem, providing additional insights into the complex interactions. Recent hybrid centrifuge tests using the Coupled Centrifuge-Numerical Modelling (CCNM) approach have provided high-quality experimental data of soil-piled structure interactions in dry sand, demonstrating the role of structure stiffness on head load transfer among piles and the subsequent impact on pile shaft resistance with tunnel volume loss. Geotechnical centrifuge modelling has been widely used as a tool to study problems related to tunnelling activities and its interaction with existing infrastructure systems. All new weapons and armor come with their counterparts.Tunnel excavation in urban areas causes ground movements that could damage existing nearby piled structures. Additionally, there are 4 new armor sets-the Rubicon Hardplate, HVM Carbon Fibre, Atomic Medusa, and Shotlite Dragonfly series. In addition, the pack included 20 new weapons for the Rubicon, Critical Mass, Smokestack, HIKS, Teknoboom, Rancor, Ronson, and Shotlite industries. The expansion pack included 2 new classes of weapons- lasers and disc throwers. The first Expansion Pack for SAS: Zombie Assault 4 was released for Flash on Decemand for mobile in version 1.4.
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