Long-term field study of a deep-corrugated metal box type culvert

1994 ◽  
Vol 31 (2) ◽  
pp. 175-180 ◽  
Author(s):  
Shad M. Sargand ◽  
Glenn A. Hazen ◽  
Teruhisa Masada ◽  
John O. Hurd
Keyword(s):  
Field Performance ◽  
Reference Points ◽  
Load Test ◽  
Static Load Test ◽  
Static Loads ◽  
Long Term Study ◽  
Corrugated Metal ◽  
Over Time ◽  
Term Field

A deep-corrugated metal box culvert structure was instrumented with strain gages and tape extensometer reference points in the field. Performance was monitored during backfilling and, paving and under static loads shortly after completion of installation. Beyond the initial study, deflection readings were taken periodically for 3 years. Also, the static load test was conducted during the second and third years to examine changes in structural responses over time. The results of the study showed that the culvert deflection stabilized within the 3 year period. The overall deflection recorded during the construction phases was about 2 cm, and the additional deflection of about 0.8 cm took place during the long-term study period. The deflection, moment, and thrust responses of the culvert under static loads improved over time. This was considered to be because of backfill soil densification under repeated traffic loads. Key words : long-term field performance, culvert, box type, deep corrugation, deflection, live loads.

Predicting the Long-Term Field Performance of Coating Systems on Steel Using a Rapid Electrochemical Test: The Damage Tolerance Test

CORROSION ◽  
2012 ◽  
Vol 68 (3) ◽  
pp. 035007-1-035007-13 ◽  
Author(s):  
S.R. Taylor ◽  
F. Contu ◽  
L.M. Calle ◽  
J.P. Curran ◽  
W. Li
Keyword(s):  
Damage Tolerance ◽  
Field Performance ◽  
Tolerance Test ◽  
Electrochemical Test ◽  
Term Field

scholarly journals Monitoring of agrophysical properties of the active layer of drained long-frozen peat deposits in Western Siberia

2020 ◽  
Vol 164 ◽  
pp. 07016
Author(s):  
Vasily Novokhatin ◽  
Nadezhda Osipova
Keyword(s):  
Western Siberia ◽  
Soil Reclamation ◽  
Hydromorphic Soils ◽  
Investment Projects ◽  
Long Term Study ◽  
Peat Deposits ◽  
Changes Over Time ◽  
Reclaimed Soils ◽  
Over Time

In this study, the authors considered the dynamics of the main agrophysical properties of hydromorphic geosystems in Western Siberia. In the process of evolution, as well as in the conditions of technogenic impact, the soils of natural-territorial complexes, their properties are subject to significant changes. New hydromorphic geosystems are formed, the soils of which are characterized by changed agrophysical properties. Modern technologies for developing investment projects for soil reclamation of hydromorphic geosystems should be based on agrophysical characteristics of reclaimed soils, on the basis of which it is possible to create the necessary parameters of drainage systems and, as a result, provide optimal soil regimes for agricultural crops for a long period. The difficulty is that these soil characteristics are variable over time. Until recently, agrophysical characteristics of soils obtained in other regions of the country were used in the development of reclamation projects for hydromorphic soils in Western Siberia. The attempt to borrow them has led to the fact that large areas of drained soil have become completely unsuitable and to restore their project productivity, a number of agro-reclamation activities and the attraction of large financial resources are currently required. In this regard, there is a need for a comprehensive, long-term study of the main properties of hydromorphic soils used for agricultural purposes, and especially their changes over time under the influence of anthropogenic load.

scholarly journals Pingo Growth and collapse, Tuktoyaktuk Peninsula Area, Western Arctic Coast, Canada: a long-term field study

2002 ◽  
Vol 52 (3) ◽  
pp. 271-323 ◽  
Author(s):  
J. Ross Mackay
Keyword(s):  
Freezing Point ◽  
Growth Data ◽  
Long Term Study ◽  
Western Arctic ◽  
Mound Growth ◽  
Arctic Coast ◽  
Spring Flow ◽  
Potential Use ◽  
Term Field

Abstract Growth data from precise surveys have been obtained for 11 pingos for periods ranging from 20 to 26 years. Most of the 1350 pingos, perhaps one quarter of the world's total, have grown up in the bottoms of drained lakes underlain by sands. Permafrost aggradation on the drained lake bottoms has resulted in pore water expulsion, solute rejection below the freezing front, a freezing point depression, and groundwater flow at below 0° C to one or more residual ponds, the sites of pingo growth. Sub-pingo water lenses underlie many growing pingos.The pure ice which grows by downward freezing in a sub-pingo water lens may be composed of seasonal growth bands which, like tree rings, are of potential use in the study of past climates. Growing pingos underlain by sub-pingo water lenses can often be identified by features such as peripheral pingo rupture, spring flow, frost mound growth, normal faulting, and oscillations in pingo height. Such features, and others, are associated with hydrofracturing and water loss from a sub-pingo water lens. Some of the data derived from the long-term study of pingo growth are relevant to the identification of collapse features, interpreted as paleo pingos, in areas now without permafrost.

Long-term study of root biomass in a biodiversity experiment reveals shifts in diversity effects over time

Oikos ◽  
2014 ◽  
Vol 123 (12) ◽  
pp. 1528-1536 ◽  
Author(s):  
Janneke M. Ravenek ◽  
Holger Bessler ◽  
Christof Engels ◽  
Michael Scherer-Lorenzen ◽  
Arthur Gessler ◽  
...  
Keyword(s):  
Root Biomass ◽  
Term Study ◽  
Long Term Study ◽  
Diversity Effects ◽  
Over Time

scholarly journals Spread parameters of the borer Xylotrechus Arvicola (Olivier) (Coleoptera: Cerambycidae) in a ‘Tempranillo’ vineyard in La Rioja (Spain): A long-term study

2020 ◽  
Vol 35 (2) ◽  
pp. 148-166 ◽  
Author(s):  
Rafael Ocete ◽  
Ignacio Armendáriz ◽  
Carlos A. Ocete ◽  
Lara Maistrello ◽  
José M. Valle ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Bimodal Distribution ◽  
Linear Increase ◽  
Term Study ◽  
Progressive Decline ◽  
Long Term Study ◽  
Spread Parameters ◽  
La Rioja ◽  
Over Time

Xylotrechus arvicola (Olivier) (Coleoptera: Cerambycidae) is a polyphagous xylophagous beetle that is becoming a pest of increasing importance for vineyards in Spain, also because of the wood fungi developing in the galleries excavated by its larvae, which cause a progressive decline of the affected grapevines, until death. Between 1993 and 2015, a survey of the infestation caused by X. arvicola and the symptoms caused by pathogenic wood fungi was performed in a ‘Tempranillo’ variety vineyard in La Rioja region (Spain). Maps showing the overtime spread of the borer and the diffusion of symptoms of grapevine decline and Eutypa dieback were obtained. Results indicated that the borer colonization began in the centre of the plot, followed by the first symptoms caused by the wood fungi a few years later. The statistical analysis showed that the evolution of infestation is characterized by a linear increase of new holes whereas the pattern of their allocation in the vines follows a bimodal distribution which, to some extent, can be simulated by a Poisson’s model. Based on these observations, a methodology to estimate the state of the infestation over time is proposed. The procedure - based on a linear regression of the average number of holes per vine over a set of years - can be applied in a relatively simple way and provides the probability for a grapevine to have a certain number of exit holes in a definite year with a mean error of around 5%.

scholarly journals Energy Efficient Wireless Sink Node for Monitoring of Snow Environment

2021 ◽  
Vol 12 (2) ◽  
pp. 1775-1785
Author(s):  
Rajesh Kumar Garg, Et. al.
Keyword(s):  
Energy Efficient ◽  
Snow Depth ◽  
Field Performance ◽  
Cost Effective ◽  
Field Evaluation ◽  
Sink Node ◽  
Depth Sensor ◽  
Power Module ◽  
Term Field

Conventionally, sink node is considered to have large hardware and energy resources; however, many times sink node is working in same conditions as source nodes, especially when deployed for monitoring of the snow environment. In this paper, an effort has been made to practically realize a sink node which is energy efficient and cost effective for monitoring applications. To save energy, the Main Power Module is designed to provide controlled powers to sensors and sub-modules. The paper discusses design aspects of the sink node and its long-term field evaluation with environmental sensors, especially the Snow Depth Sensor of MaxBotix. Field performance of Snow Depth Sensor has been enhanced by Euclidean Minimum Distance filter which improved the correlation of data to 0.997. The proposed design helps to achieve energy consumption of 42.72mWh which is significantly lower than the previous work. The reliable working of the sink node in the long-term field evaluation indicates that snow environment can be monitored at less expense of energy by employing proposed sensors and the specially designed sink node.

scholarly journals ANALISIS KEKUATAN STRUKTUR KERETA BARANG “FLAT WAGON” = STRENGTH ANALYSIS OF FLAT WAGON STRUCTURES

2014 ◽  
Vol 14 (1) ◽  
pp. 19
Author(s):  
Anwar . ◽  
Ade Ruhimat
Keyword(s):  
Maximum Stress ◽  
Base Material ◽  
Load Test ◽  
Strength Analysis ◽  
Vertical Load ◽  
Static Load Test ◽  
Static Loads ◽  
Compression Load ◽  
National Regulation ◽  
As Stress

This paper describes strength analysis for the flat wagon. The analysis is conducted by experiment methods using testing the flat wagon prototype with static loads such as vertical load, compression load, twist load, jacking load, and combination of them.The result of test such as stress and camber is analyzed against the design requirement and national regulation to assess the reliability of the flat wagon structure.The result of test shows that the critical area under compression load and vertical load occurs at the “end center sill” and the “central center sill”, respectively. Maximum stress of the flat wagons structure is 271.32 N/mm2 equal to 76.4% of yield stress of base material. It occurs at combination of vertical and compression loads. It indicates that the flat wagon structure is feasible to be operated with maximum capacity of 40 tons.Keywords : flat wagon, static load test, compression load, stress analysis.Abstrak Makalah ini membahas analisis kekuatan struktur gerbong kereta barang tipe gerbong datar (flat wagon). Analisis dilakukan dengan menguji prototipe struktur flat wagon secara eksperimental dengan jenis beban statis yang terdiri dari beban vertikal, kompresi, twist, jacking, dan kombinasi.Hasil pengujian berupa besaran tegangan dan camber, dianalisis terhadap persyaratan desain dan peraturan menteri untuk menilai kelayakan dari struktur flat wagon.Dari hasil pengujian diperoleh titik kritis akibat beban kompresi adalah di lokasi ”end center sill”, sedangkan akibat beban vertikal, adalah di lokasi ”central center sill”. Tegangan terbesar yang terjadi akibat pengujian yaitu sebesar 271.32 N/mm2 atau setara dengan 76.4% dari tegangan yield material dasarnya, terjadi pada kondisi beban kombinasi antara beban vertikal dan beban kompresi.Dari analisis dan verifikasi hasil uji terhadap persyaratan desain dan peraturan menteri, disimpulkan bahwa struktur flat wagon mampu dan layak digunakan dengan kapasitas daya angkut maksimum 40 ton.Kata Kunci : gerbong datar, uji beban statis, beban kompresi, analisis tegangan.

scholarly journals Simulation and design of collector array units within large systems

2019 ◽  
Author(s):  
Simon Furbo ◽  
Weiqiang Kong ◽  
Jianhua Fan
Keyword(s):  
Performance Prediction ◽  
Field Performance ◽  
Operating Conditions ◽  
Test Information ◽  
Large Systems ◽  
Term Field

Investigation of measured long-term field performance in relation to standardized collector test information and tools/models for annual performance prediction at different operating conditions and field designs.

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