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As the worlds first floating wind farm, one of the main technical challenges in the design phase of Hywind Scotland was the uncertainty related to wake interaction effects between the floating wind turbines. In this paper, we address this challenge by presenting an analysis of full‐scale measurements from the Hywind Scotland wind farm. Measurements of the floaters' roll, pitch and yaw motions are presented, both in the form of statistical data and response spectra. The floater responses of a turbine in free wind and a turbine in wake are compared, and the influence of different atmospheric stabilities on the floater motions is investigated. Despite the large distance between the turbines of 9 rotor diameters, wake effects in the measured floater motions are observed at the downstream turbine. Furthermore, both the wake responses and the free wind responses show a clear dependency on atmospheric stability. However, overall motions are small for all wind speeds, showing that the design performs satisfactorily in both free wind and wake conditions.

To explore the load-bearing performance and the failure patterns of the lining structures, a full-scale loading test on the three-ring staggered assembled shield tunnel segments is carried out through a hydraulic loading system. In the experimental study, the segments’ internal force, convergence deformation, and displacement, and the bolts’ internal force, are analyzed. According to the experimental results, the relationship between internal force and deformation is obtained to determine the residual bearing capacity of the shield tunnel at each stage. Three stages are specified for the evolution of the segment’s maximum bending moment during the loading process, in which, the elastic stage is the main and longest stage, in which the bending moment of the segment increases the most. There are two stages for convergence deformation development and segment misalignment development. At the end of loading, the segment’s maximum positive and negative convergence values reach 61.22 and −57.69 mm, respectively. Besides, the maximum segment misalignment is 3.67 mm, which occurs in the direction of 90°. The segment cracks when its maximum convergence value reaches 25.03 mm. Moreover, there are signs of fracturing on the waist joint of the segment when its maximum convergence value reaches 32.73 mm. The concrete at the waist joint starts fracturing in pieces when the segment’s maximum convergence value reaches 38.93 mm, which is defined as the type of shear failure. Finally, the bearing capacity of shield tunnels during segment failure period can be evaluated by using the corresponding relationship between deformation and internal force.

The hippocampus is a key brain region for memory and cognitive functions, which consists of distinct subregions with different developmental trajectories throughout adolescence. However, trajectories of hippocampal subfield change in young adulthood remain uncharacterized, as is their potential relationship with cortical brain aging and cognitive ability during this time. We conducted two magnetic resonance imaging (MRI) follow‐ups of a prenatal birth cohort in young adulthood and studied the effects of chronological age and cortical brain age on the volume of hippocampal subfields in the early 20s (n = 109; 51% men) and late 20s (n = 251; 53% men) and how these age‐related volumetric changes might relate to full‐scale IQ (FSIQ). We showed that CA1 and CA4DG subfields continue to grow in the third decade of life and that this growth can be observed both at the level of chronological age as well as estimated cortical brain age at both MRI timepoints. Moreover, in men, a larger size of these age‐related subfields was associated with higher FSIQ, and the deviations between cortical brain age and chronological age mediated the relationships between right CA1 and FSIQ, as well as right CA4DG and FSIQ. These findings reveal that coordinated patterns of advanced cortical brain aging and hippocampal maturation may confer a cognitive advantage in young adulthood. Hippocampal subfields continue to develop in young adulthood, and in young adult men, the deviations between one's global cortical brain age and chronological age mediate the relationship between the size of CA1 and CA4DG and full‐scale IQ. These findings suggest that faster brain maturation early on is beneficial.

Geotechnical engineering projects involving retaining walls require the calculation of lateral earth pressures behind these walls. This paper assesses several analytical solutions available in the literature for the calculation of at-rest, active, and passive lateral earth pressures behind rigid retaining walls. The calculated lateral earth pressures from these analytical solutions are compared with the measured values from small-scale tests, full-scale tests, and/or numerical simulations available in the literature. Small-scale tests showed similar normalized at-rest, active and passive lateral earth pressures as compared with full-scale tests/numerical simulations. The comparisons show that the calculated lateral thrust using the method by Jaky (J Soc Hung Archit Eng 78:355–358, 1944) and Janssen (Verein Deutscher Ingenieure, 39: 1045-1049, 1895) with a low wall-soil interface friction angle well matched the measured at-rest lateral thrust in the field tests and those by Coulomb (Essai sur une application des règles de maximis et minimis a quelques problèmes de statique, relatifs a l’architecture, Academie Royale Des Sciences, Paris, 1776) and Zhou et al. (Rock Soil Mech 35:245–250, 2014) agreed better with the measured passive lateral thrusts in the small-scale tests and full-scale numerical simulations than those by other methods. The calculated lateral thrusts using the methods by Coulomb (Essai sur une application des règles de maximis et minimis a quelques problèmes de statique, relatifs a l’architecture, Academie Royale Des Sciences, Paris, 1776), and Handy (J Geotech Eng 111:302–318, 1985) and Paik and Salgado (Geotechnique 53:643–653, 2003) with appropriate wall-soil interface friction angles matched the active thrusts in both small-scale and full-scale tests reasonably well.

Strong excitation effect on the outer windshield structure induced by unsteady airflow around the connection between carriages has been normally detected in full-scale tests, which leads to violent vibration of the outer windshields due to strong nonlinear fluid–structure interaction (FSI) between the flow field and the structure. Previous studies normally treat the outer windshield structure as rigid bodies, and the coupling effect between unsteady flow and elastic structure has not been considered. The purpose of this study is to establish a two-way iterative FSI model based on a full-scale test, obtain the flow field characteristics around the outer windshields through FSI simulation, and analyze their vibration mechanism and characteristics. The results show that the iterative computing of two-way coupling has good applicability for the analysis of the vibration of the outer windshields of a high-speed train (HST). The relative deviation of the surface pressure of the outer windshield between the test and simulation is 4.3%, and the relative deviation of the main frequency of pressure change is 1.9%. Under the action of aerodynamic loading, two opposite U-section rubber capsules produce dislocation deformation movement, which produces bending deformation, and the deformation vibration frequency is close to the first-order natural frequency of the structure. Then, under the coupling action of aerodynamic, elastic, and inertial forces, the vibration mode close to the high-order natural frequency of the outer windshield structure is excited, and the displacement phase of the outer windshield presents prominent periodicity. This study can provide a reference for the study of aeroelastic problems of the external structure of HSTs.

Accelerated epigenetic aging has been associated with changes in cognition. However, due to the lack of neuroimaging epigenetics studies, it is still unclear whether accelerated epigenetic. Aging in young adulthood might underlie the relationship between altered brain dynamics and cognitive functioning. We conducted neuroimaging epigenetics follow‐up of the European Longitudinal Study of Pregnancy and Childhood (ELSPAC) prenatal birth cohort in young adulthood and tested the possible mediatory role of accelerated epigenetic aging in the relationship between dynamic functional connectivity (DFC) and worse cognition. A total of 240 young adults (51% men; 28–30 years, all of European ancestry) participated in the neuroimaging epigenetics follow‐up. Buccal swabs were collected to assess DNA methylation and calculate epigenetic aging using Horvath's epigenetic clock. Full‐scale IQ was assessed using the Wechsler adult intelligence scale (WAIS). Resting‐state functional magnetic resonance imaging (rs‐fMRI) was acquired using a 3T Siemens Prisma MRI scanner, and DFC was assessed using mixture factor analysis, revealing information about the coverage of different DFC states. In women (but not men), lower coverage of DFC state 4 and thus lower frequency of epochs with high connectivity within the default mode network and between default mode, fronto‐parietal, and visual networks was associated with lower full‐scale IQ (AdjR2 = 0.05, std. beta = 0.245, p = 0.008). This relationship was mediated by accelerated epigenetic aging (ab = 7.660, SE = 4.829, 95% CI [0.473, 19.264]). In women, accelerated epigenetic aging in young adulthood mediates the relationship between altered brain dynamics and cognitive functioning. Prevention of cognitive decline should target women already in young adulthood. Neuroimaging epigenetics follow‐up of a prenatal birth cohort reveals that in women, accelerated epigenetic aging in young adulthood might alter brain dynamics leading to worse cognition.

To reduce the maintenance requirements during the service life of highway bridges and enhance the cracking resistance of concrete slabs in the hogging moment zone of continuous composite girders, this paper proposes an innovative girder-to-pier joint for composite bridges with integral piers. Compared to the existing ones, this new joint has structural differences. The middle part of the embedded web is hollowed out to facilitate the construction, and the upper and bottom flanges of the steel girder within this joint are widened. Moreover, cast-in-place ultra-high-performance concrete (UHPC) is applied instead of normal concrete (NC) only on the top surface of the pier. A full-scale test was carried out for this new joint to evaluate the load–displacement relationship, load–strain relationship, crack initiation, and crack propagation. Compared with the numerical simulation results of the reference engineering, the test results demonstrated that the proposed joint exhibited excellent flexural performance and cracking resistance. This paper also proposes a calculation method for the elastic flexural capacity of the girder-to-pier joint incorporating the tensile strength of UHPC, and the calculated result was in good agreement with the experimental result.

When subjected to external loads from the ground and nearby construction, tunnel segmental lining joints are prone to damaging deformation. This can result in water leakage into tunnels, posing great safety risks. With this issue in mind, we conducted a series of full-scale tests to study the effects of external loads on the waterproofing performance of longitudinal joints. A customized rig for testing segmental joints was developed to assess the effect of loading magnitude, eccentricity, and loading-unloading-reloading cycles on waterproofing performance. Additionally, the relationship between joint force, sealing gasket deformation, and waterproofing pressure was investigated. The results indicate that: (1) the sealing gasket’s compression rapidly decreases as external loads increase, which weakens the waterproofing capacity of the joint; (2) the watertightness limit dramatically decreases as the bending moment increases; (3) a loading-unloading-reloading cycle leads to degradation of the joint’ s waterproofing performance. The findings of this study provide a reference for subsequent waterproofing design of segmental tunnel joints, helping ensure the safety of tunnels throughout their operational lifespans.

A comprehensive laboratory testing program, field-testing program, numerical analysis, and life-cycle cost analysis were conducted to evaluate the beneficial effects of incorporating shrinkage-reducing admixture (SRA), polymeric microfibers (PMFs), and optimized aggregate gradation (OAG) into internally cured concrete (ICC) mixtures for rigid pavement applications. Results from the laboratory program indicate that all the ICC mixtures outperformed the standard concrete (SC) mixture. All the ICC mixtures showed a decrease in drying shrinkage compared to the SC mixture. Based on the laboratory program, three ICC mixtures and one SC mixture were selected for the full-scale test and subjected to a heavy vehicle simulator for accelerated fatigue testing. Extensive testing and analysis have shown that ICC mixtures incorporating SRA, PMFs, and OAG can be beneficially used in pavement applications to achieve increased pavement life. Keywords: critical stress analysis; full-scale test slabs; internally cured concrete (ICC); optimized aggregate gradation (OAG); polymeric microfibers (PMFs); shrinkage-reducing admixture (SRA).

A new type of Filament Wound Profiles (FWPs) have been applied to strengthen the deformed stagger-jointed segmental tunnel linings, and a full-scale test was carried out on the ultimate bearing capacity of the linings that are strengthened by the new FWPs. The failure phenomena and the main experimental results were obtained, including the load-displacement curve, strain and bond failure. The internal forces of the FWPs in the strengthened lining were calculated and discussed. The failure chain and weak sections of the strengthened lining were discussed. The overall strengthening benefits were summarized. The results show that: (1) The FWPs were in the state of compression bending or tension bending, and bore part of the axial force and bending moment in the strengthened lining. (2) The initial failure of the strengthened linings was caused by the bond failure between the FWPs and the concrete linings at 0°. (3) The filament wound profiles strengthening method can effectively improve the ultimate bearing capacity and stiffness of the stagger-jointed shield tunnel linings.