Structural Performance of Bridges in the Tohoku-Oki Earthquake

2013 ◽  
Vol 29 (1_suppl) ◽  
pp. 315-338 ◽  
Author(s):  
Kazuhiko Kawashima ◽  
Ian Buckle

Including minor nonstructural damage, over 1,500 highway bridges and numerous rail bridges were damaged during the Tohoku-oki earthquake of 11 March 2011. The causes of this damage can be broadly classified in two categories: ground shaking, including ground failure (liquefaction); and tsunami inundation. Damage included span unseating, column shear and flexural failures, approach fill erosion, liquefaction induced settlement, and failed steel and elastomeric bearings. Since many bridges in the north Miyagi-ken and south Iwate-ken suffered extensive damage during the 1978 Miyagi-ken-oki earthquake, bridge performance during the 2011 earthquake is of particular interest. Advances in design and retrofit may be assessed by looking at the performance of bridges designed to post-1990 codes and those retrofitted since the Kobe earthquake in 1995. In both categories, bridge damage due to ground shaking was minor, thus validating the provisions in the post-1990 codes and the Japan bridge retrofit program. Damage that did occur due to ground shaking was mainly to bridges not yet retrofitted or only partly so. Tsunami-related damage included complete loss of span and erosion of backfills. However, many bridges survived, despite being totally submerged, and their performance gives insight into the potential design of tsunami-resistant bridges.

2020 ◽  
Vol 14 (4) ◽  
pp. 405-412
Author(s):  
Endra Gunawan ◽  
Takuya Nishimura ◽  
Susilo Susilo ◽  
Sri Widiyantoro ◽  
Nanang T. Puspito ◽  
...  

AbstractOn 6 December 2016 at 22:03 UTC, a devastating magnitude 6-class strike-slip earthquake occurred along an unidentified and unmapped fault in Pidie Jaya, northern Sumatra. We analysed the possible fault using continuous Global Positioning System (GPS) observation available in the region. In our investigation, we searched for the fault source parameters of the north- and south-dipping left-lateral faults and the west- and east-dipping right-lateral faults. We identified that the fault responsible for the earthquake was located offshore, with a southwest-northeast direction. We also computed the Coulomb failure stress and compared the result with the distribution of the aftershocks. In this study, we demonstrated that the result of the geological field survey conducted soon after the mainshock was attributed to the secondary effects of ground shaking and near-surface deformation, and not surface faulting. The newly identified offshore fault proposed by this study calls for further investigation of the corresponding submarine morphological attributes in this particular region.


Apidologie ◽  
2019 ◽  
Vol 51 (2) ◽  
pp. 180-200 ◽  
Author(s):  
Sara Rodney ◽  
Vincent J. Kramer

AbstractRecent concerns regarding potential effects of pesticides on pollinators have prompted regulatory agencies to estimate dietary ingestion rates for honey bees (Apis mellifera). The task is difficult because of the complex caste and food storage systems in honey bee colonies. Considerable data on the nutrition and energetics of honey bees have recently been collated. These data were used to parameterize a probabilistic model estimating nectar requirements of nectar foragers. Median estimates were more than 6× lower than the recommended median value from the North American government agencies, of 292 mg nectar/bee/day. The distribution of estimates had much greater variability than those of the agencies. The differences are due primarily to the disparate assumptions regarding how much time nectar foragers spend flying and foraging. Risk assessors considering honey bee dietary exposure should take account of current and emerging data providing insight into nectar forager dietary requirements, foraging activity, and feeding behavior.


2020 ◽  
Vol 18 ◽  
pp. 1-19
Author(s):  
Adrià Ramos ◽  
Berta Lopez-Mir ◽  
Elisabeth P. Wilson ◽  
Pablo Granado ◽  
Josep Anton Muñoz

The Llert syncline is located in the South-central Pyrenees, between the eastern termination of the EW-trending Cotiella Basin and the north-western limb of the NS-trending Turbón-Serrado fold system. The Cotiella Basin is an inverted upper Coniacian-lower Santonian salt-floored post-rift extensional basin developed along the northern Iberian rift system. The Turbón-Serrado fold system consists of upper Santonian – Maastrichtian contractional salt-cored anticlines developed along an inverted transfer zone of the Pyrenean rift system. Based on field research, this paper presents a 3D reconstruction of the Llert syncline in order to further constrain the transition between these oblique salt-related structures. Our results suggest that the evolution of the Llert syncline was mainly controlled by tectonic shortening related to the tectonic inversion of the Cotiella Basin synchronously to the growth of the Turbón-Serrado detachment anticline, and by the pre-compressional structural framework of the Pyrenean rift system. Our contribution provides new insight into the geometric and kinematic relationships of structures developed during the inversion of passive margins involving salt.


2017 ◽  
Vol 57 (3) ◽  
Author(s):  
Lili Zách

ABSTRACTIn the aftermath of the Great War, the birth of new independent small states in East-Central Europe was closely followed in Irish nationalist circles due to the possibility of Partition in Ireland. Newspaper editorials, journal articles and diplomatic accounts illustrate that post-war Ireland had an open attitude toward the settlement of borders on the Continent as the dissolution of the Austro-Hungarian Empire was similarly controversial. This paper aims to investigate how contemporary Irish commentators perceived the question of boundary settlements in Central Europe in order to provide an insight into the transformation of political space in both Ireland and Central Europe. After providing a brief background to the Irish boundary question, this paper touches upon the most important points in historiography with regard to border settlements in the post-World War I era.. It also discusses Irish Partition history in detail, concentrating on the North-Eastern Boundary Bureau (NEBB) and the Boundary Commission, and the importance of Central European precedents in their work. Moreover, this paper also proposes to provide an insight into the Irish interest in the minority problem in European borderland regions after 1925 in order to illustrate the outward-looking attitude to Irish nationalists, even in relation to borders and minorities.


Author(s):  
Lee M. Liberty ◽  
Zachery M. Lifton ◽  
T. Dylan Mikesell

Abstract We report on the tectonic framework, seismicity, and aftershock monitoring efforts related to the 31 March 2020 Mw 6.5 Stanley, Idaho, earthquake. The earthquake sequence has produced both strike-slip and dip-slip motion, with minimal surface displacement or damage. The earthquake occurred at the northern limits of the Sawtooth normal fault. This fault separates the Centennial tectonic belt, a zone of active seismicity within the Basin and Range Province, from the Idaho batholith to the west and Challis volcanic belt to the north and east. We show evidence for a potential kinematic link between the northeast-dipping Sawtooth fault and the southwest-dipping Lost River fault. These opposing faults have recorded four of the five M≥6 Idaho earthquakes from the past 76 yr, including 1983 Mw 6.9 Borah Peak and the 1944 M 6.1 and 1945 M 6.0 Seafoam earthquakes. Geological and geophysical data point to possible fault boundary segments driven by pre-existing geologic structures. We suggest that the limits of both the Sawtooth and Lost River faults extend north beyond their mapped extent, are influenced by the relic trans-Challis fault system, and that seismicity within this region will likely continue for the coming years. Ongoing seismic monitoring efforts will lead to an improved understanding of ground shaking potential and active fault characteristics.


Author(s):  
Chadi Mallat ◽  
Alistair Corbett ◽  
Glyn Harris ◽  
Marc Lefranc

It is reputed in the Oil & Gas industry that marine growth is overestimated in the North Sea. Can we quantify this overestimation to better tackle the challenges marine growth incurs? This paper provides insight into the intrinsic and diverse nature of marine growth. It documents the biofouling development and the factors that affect it globally. Focus is made on fixed steel platforms in the North Sea approaching the end of their economic lives. A methodology to quantify the weight of marine growth is proposed and illustrated. 28 years after its installation, the weight of marine growth accumulated on Valhall 2/4G jacket located in Southern North Sea is evaluated based on the proposed method. It is confirmed that the current regulations overestimate the weight of marine growth in the North Sea.


2021 ◽  
Author(s):  
Elgonda LaGrange

Abstract Nearly all oil and gas operators and engineering companies in the offshore sector today are engaged in programs to advance concepts for low-manned and/or normally unattended production installations (NUIs). When it comes to the design of these facilities, topsides rotating equipment and electrical, instrumentation, control, and telecommunications (EICT) packages represent key areas of interest for decision-makers, owing to the significant impact they can have on required manning levels. Over the past decade, the author's company has worked closely with major Operators in the U.S. and the North Sea to look at how existing technologies can be applied in these areas to safely facilitate de-manning of both brownfields and greenfields. This paper provides insight into these efforts. It also presents projected manpower and cost savings from de-manning, using data derived from both studies and real-world projects.


2021 ◽  
pp. 136943322110480
Author(s):  
Yan Wang ◽  
Dong-Hui Yang ◽  
Yu-Zheng Zhou ◽  
Ting-Hua Yi

The cables of long-span cable-stayed bridges are subjected to substantial tension during long-term service and are more susceptible to corrosion and fatigue failure than concrete structures. Most existing structural health monitoring (SHM) systems do not have monitoring equipment to directly measure cable length, and long-term monitoring of the change in cables is less involved. The displacement response of a bridge is induced by the combination of dynamic effects (wind and highways) and quasi-static effects (temperature). In this paper, the dynamic responses were eliminated by averaging the displacement data for 10 min, and the relationship between temperature and displacement was studied. Based on the monitoring data, the distribution of the thermal field for the bridge was studied and the time variability of the tower displacement was investigated. The correlation was analyzed to study the relationship between the temperature and the tower displacements, the north tower–south tower distance and the tower–girder distances. A strong linear relationship between the temperature and quasi-static responses of the displacements was observed. The thermal expansion coefficient of the effective length of cables was proposed as a quantitative index for long-term cable monitoring. The error in the cable effective length is proposed as the warning index for performance warning research. The results show that the proposed performance warning method can monitor cables and perform warnings when the cable is damaged.


2021 ◽  
Vol 36 (1) ◽  
pp. 155-164
Author(s):  
Richard Barnes

Abstract On 30 September 2020, the United Kingdom and Norway signed the Framework Agreement on Fisheries that will provide the basis for future cooperation in the sustainable management of their fisheries. The Agreement is the first such agreement adopted by the UK following its decision to the leave the European Union. This note provides some background to the Agreement and examines its key features. Whilst the content of the Agreement appears to be rather basic, this is broadly consistent with other framework agreements, and it does provide some insight into the direction and focus of fisheries management in the North Sea, and how cooperation may develop between coastal States and the European Union.


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