SUMMARYThe seismic performance of the Bolu Viaduct in the Duzce, Turkey, earthquake of November 1999 was studied via a non-linear, time-history analysis of a multi-degree of freedom model. The viaduct had a seismic isolation system consisting of yielding-steel energy dissipation units and sliding pot bearings. The Duzce earthquake caused a surface rupture across the viaduct, which resulted in excessive superstructure movement and widespread failure of the seismic isolation system. The e ect of the rupture was modeled by a static, di erential ground displacement in the fault-parallel direction across the rupture. The ground motions used in the analysis contain common near-fault features including a directivity pulse in the fault-normal direction and a ing step in the fault-parallel direction. The analysis used a ÿnite element package capable of modeling the mechanical behavior of the seismic isolation system and focused on the structural response of a 10-span module of the viaduct. This analysis showed that the displacement of the superstructure relative to the piers exceeded the capacity of the bearings at an early stage of the earthquake, causing damage to the bearings as well as to the energy dissipation units. The analysis also indicated that shear keys, both longitudinal and transverse, played a critical role in preventing collapse of the deck spans. Published in 2004 by John Wiley & Sons, Ltd.

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Abstract. We present a satellite-derived global dust climatological record over the last two decades, including the monthly mean visible dust optical depth (DAOD) and vertical distribution of dust extinction coefficient at a 2º (latitude) × 5º (longitude) spatial resolution derived from CALIOP and MODIS. Dust is distinguished from non-dust aerosols based on particle shape information (e.g., lidar depolarization ratio) for CALIOP, and on dust size and absorption information (e.g., fine-mode fraction, Angstrom exponent, and single-scattering albedo) for MODIS, respectively. On multi-year average basis, the global (60° S–60° N) and annual mean DAOD is 0.029 and 0.063 derived from CALIOP and MODIS retrievals, respectively. In most dust active regions, CALIOP DAOD generally correlates well with the MODIS DAOD, with CALIOP DAOD being significantly smaller. CALIOP DAOD is 18 %, 34 %, 54 % and 31 % smaller than MODIS DAOD over Sahara Deserts, the tropical Atlantic Ocean, the Caribbean Sea, and the Arabian Sea, respectively. Over East Asia and the northwestern Pacific Ocean (NWP), however, the two datasets show weak correlation. Despite these discrepancies, CALIOP and MODIS show similar seasonal and interannual variations in regional DAOD. For dust aerosol over NWP, both CALIOP and MODIS show a declining trend of DAOD at a rate of about 2 % yr−1. This decreasing trend is consistent with the observed declining trend of DAOD in the southern Gobi Desert at a rate of −3 % yr−1 and −5 % yr−1 according to CALIOP and MODIS, respectively. The decreasing trend of DAOD in the southern Gobi Desert is in turn found to be significantly correlated with an increasing trend of vegetation and a decreasing trend of surface wind speed in the area.

Scour was responsible for most of the US bridges that collapsed during the past 40 years. Due to erosion and refilling of riverbed deposits under strong current, the maximum scour depth is difficult to measure with existing technologies during a flood event. In this study, a new methodology is proposed to embed permanent magnets in a natural rock and integrate the so-called smart rock into the process of bridge scour for real-time monitoring. Once properly designed, the smart rock can continually fall into the bottom of a gradually growing scour hole during a flood event and thus register the maximum scour depth. Emphasis in this study is placed on the working principle of smart rocks, the maximum measurement distance with a magnetometer, and various calibration and validation tests. It was demonstrated that the magnetic field intensity is a function of measurement distance and magnet orientation and, once calibrated, can be strongly correlated with the increase in scour depth over time.

Gender identity is a core component of human experience, critical to account for in broad health, development, psychosocial research, and clinical practice. Yet, the psychometric characterization of gender has been impeded due to challenges in modeling the myriad gender self-descriptors, statistical power limitations related to multigroup analyses, and equity-related concerns regarding the accessibility of complex gender terminology. Therefore, this initiative employed an iterative multi-community-driven process to develop the Gender Self-Report (GSR), a multidimensional gender characterization tool, accessible to youth and adults, nonautistic and autistic people, and gender-diverse and cisgender individuals. In Study 1, the GSR was administered to 1,654 individuals, sampled through seven diversified recruitments to be representative across age (10–77 years), gender and sexuality diversity (∼33% each gender diverse, cisgender sexual minority, cisgender heterosexual), and autism status (>33% autistic). A random half-split subsample was subjected to exploratory factor analytics, followed by confirmatory analytics in the full sample. Two stable factors emerged: Nonbinary Gender Diversity and Female–Male Continuum (FMC). FMC was transformed to Binary Gender Diversity based on designated sex at birth to reduce collinearity with designated sex at birth. Differential item functioning by age and autism status was employed to reduce item–response bias. Factors were internally reliable. Study 2 demonstrated the construct, convergent, and ecological validity of GSR factors. Of the 30 hypothesized validation comparisons, 26 were confirmed. The GSR provides a community-developed gender advocacy tool with 30 self-report items that avoid complex gender-related “insider” language and characterize diverse populations across continuous multidimensional binary and nonbinary gender traits.

Article history: Available online xxx Keywords: Bridge Reliability assessment Multiple hazards Load Resistance a b s t r a c t The strength limit state of American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications is developed based on the failure probabilities of the combination of non-extreme loads.The proposed design limit state equation (DLSE) has been fully calibrated for dead load and live load by using the reliability-based approach. On the other hand, most of DLSEs in other limit states, including the extreme events Ⅰ and Ⅱ, have not been developed and calibrated though taking certain probability-based concepts into account. This paper presents an assessment procedure of highway bridge reliabilities under the limit state of extreme event Ⅰ, i. e., the combination of dead load, live load and earthquake load. A force-based approach and a displacement-based approach are proposed and implemented on a set of nine simplified bridge models. Results show that the displacement-based approach comes up with more convergent and accurate reliabilities for selected models, which can be applied to other hazards. © 2015 Periodical Offices of Chang'an University. Production and hosting by Elsevier B.V. on behalf of Owner. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).