Degradation of permafrost beneath a road embankment enhanced by heat advected in groundwater1This article is one of a series of papers published in this CJES Special Issue on the theme of Fundamental and applied research on permafrost in Canada.

2012 ◽  
Vol 49 (8) ◽  
pp. 953-962 ◽  
Author(s):  
Isabelle de Grandpré ◽  
Daniel Fortier ◽  
Eva Stephani
Keyword(s):  
Groundwater Flow ◽  
Soil Layer ◽  
Permafrost Degradation ◽  
Soil Consolidation ◽  
Monitoring Wells ◽  
The Road ◽  
Road Pavement ◽  
Advective Heat Transfer ◽  
Road Data ◽  
Northwestern North America

For the past few decades, northwestern North America has been affected by climate warming, leading to permafrost degradation and instability of the ground. This is problematic for all infrastructure built on permafrost, especially roads and runways. Thaw settlement and soil consolidation promote embankment subsidence and the development of cracks, potholes, and depressions in road pavement. In this study, we investigate highway stability in permafrost terrain at an experimentally built road embankment near Beaver Creek, Yukon. A network of 25 groundwater monitoring wells was installed along the sides of the road to estimate groundwater flow and its thermal impact on the permafrost beneath the road. Data on topography, water-table elevation, ground temperature, and stratigraphy of the soil were collected at the site. The geotechnical properties of each soil layer were determined by laboratory analysis and used to calibrate a two-dimensional groundwater flow model. Field observations showed that water was progressively losing heat as it flowed under the road embankment. Our results suggest that advective heat transfer related to groundwater flow accelerated permafrost degradation under the road embankment.

scholarly journals STUDI PERBANDINGAN MENGENAI PERHITUNGAN BESARAN REGANGAN DI LAPISAN SUBGRADE AKIBAT BEBAN RODA KENDARAAN UNTUK JALAN RAYA KELAS I

2020 ◽  
Vol 3 (4) ◽  
pp. 1077
Author(s):  
Leonardo Lijuwardi ◽  
Gregorius Sandjaja Sentosa
Keyword(s):  
Flexible Pavement ◽  
Layer System ◽  
The Road ◽  
Strain Calculation ◽  
Road Pavement ◽  
Large Contact Area ◽  
Vehicle Loads ◽  
Pavement Layers ◽  
Road Data ◽  
Pavement Thickness

ABSTRACTMulti-layer systems theory is one of the concepts used in finding out the amount of strain and stress that occurs in the road pavement system due to vehicle loads. The purpose and goal of this study is to analyze the amount of strain that occurs on the pavement systems in Indonesia, especially in the subgrade position. The type of multi-layer system theory used to calculate the amount of strain includes the theory of one layer systems, two-layer systems and three-layer systems with data analyzed in the form of pavement thickness and type of pavement material.Based on this study, the value of strain obtained by the theory of one-layer system in some of the road data reviewed are 533.8658 microstrains, 361.3456 microstrains, 1577.987601 microstrains, 618,012 microstrains and 140.3075 microstrains. For research with two-layers systems, the results obtained are 1116.2920 microstrains, 544.322 microstrains, 1448.0839 microstrains, 734.1844 microstrains and 738.7226 microstrains. For research with three-layers system, results obtained are 72.20275278; 70.80346908; 192.9638366; 123.1150377dan 391.8845636 microstrains. The results with the calculation of one-layer system are very large because the modulus values of the subgrade layers are not reviewed and only pavement thickness is reviewed. As for calculations with the theory of two-layer systems, the results obtained are far greater than one-layer systems, due to the limitations of the graph to find the value of the ratio between thickness and large contact area. Calculation with the theory of three-layers system is a strain calculation which has a much smaller value compared to the theory of one-layer system and two- layer system. This is because this theory divides the calculated pavement layers into three layers, which is in accordance with the flexible pavement system which divides the pavement layers into three layers, so this calculation is the most ideal calculation because it approaches its original condition.ABSTRAKTeori sistem lapis banyak merupakan salah satu konsep yang digunakan dalam mencari tahu besaran regangan dan tegangan yang terjadi pada sistem perkerasan jalan raya akibat beban kendaraan. Maksud dan tujuan dari penelitian ini adalah untuk menganalisis mengenai besaran regangan yang terjadi pada jalan raya di Indonesia pada lapisan tanah dasar khususnya di posisi permukaan tanah dasar. Adapun jenis teori sistem lapis banyak yang digunakan untuk menghitung besaran regangan tersebut antara lain teori one-layer systems, two-layers systems dan three-layers systems dengan data yang dianalisis berupa tebal perkerasan dan jenis material perkerasan jalan.Berdasarkan penelitian ini, adapun nilai dari regangan yang diperoleh dengan teori one-layer system di beberapa data jalan yang ditinjau, antara lain 533.8658 mikrostrain, 361.3456 mikrostrain, 1577.987601 mikrostrain, 618.012 mikrostrain dan 140.3075 mikrostrain. Untuk penelitian dengan two-layers system diperoleh hasil yaitu 1116.2920 mikrostrain, 544.322 mikrostrain, 1448.0839 mikrostrain, 734.1844 mikrostrain dan 738.7226 mikrostrain. Untuk penelitian dengan three-layers system diperoleh hasil antara lain 72.20275278; 70.80346908; 192.9638366; 123.1150377 dan 391.8845636 mikrostrain. Hasil dengan perhitungan one-layer system sangat besar dikarenakan nilai modulus lapisan dari subgrade tidak ditinjau dan hanya meninjau tebal perkerasan. Adapun untuk perhitungan dengan teori two-layers system, hasil yang diperoleh jauh lebih besar daripada one-layer system, yang disebabkan keterbatasan dari grafik untuk mencari nilai perbandingan antara ketebalan dan luas kontak yang besar. Perhitungan dengan teori three-layers system merupakan perhitungan regangan yang memiliki nilai jauh lebih kecil dibandingkan dengan teori one-layer system dan two-layer systems. Hal ini dikarenakan teori ini membagi lapisan perkerasan yang dihitung menjadi tiga buah lapisan, yang sesuai dengan sistem perkerasan lentur yang membagi lapisan perkerasan menjadi tiga buah lapisan, sehingga perhitungan ini merupakan perhitungan yang paling ideal karena mendekati kondisi aslinya.

Mechanical effects and paradoxical phenomena in the thermoelastic stress of the road pavement structures

2018 ◽  
pp. 128-145
Author(s):  
Volodynyr Mozghovyi ◽  
◽  
Viktor Gaidaichuk ◽  
Yurii Zaiets ◽  
Liudmyla Shevchuk ◽  
...  
Keyword(s):  
Thermoelastic Stress ◽  
The Road ◽  
Mechanical Effects ◽  
Road Pavement ◽  
Pavement Structures

scholarly journals The use of cement concrete pavements for roads, depending on climatic conditions

2019 ◽  
Vol 13 (3) ◽  
pp. 235-240
Author(s):  
Iryna Solonenko
Keyword(s):  
European Union ◽  
Statistical Models ◽  
Road Network ◽  
The European Union ◽  
Rational Selection ◽  
Cement Concrete ◽  
The Road ◽  
Road Pavement ◽  
Operational Characteristics ◽  
Selection Of

The development of road network infrastructure is an important component of the economic development of the European Union. Updating of the road network contributes to the integration of the economies of countries into a coherent whole. The road network provides the free movement of citizens, the movement of goods and the effective implementation of various services. The increase in the length of the road network leads to an increase in the financial and material costs necessary to ensure its maintenance and repair. One of the ways to reduce costs is by strengthening the physic-mechanical and operational characteristics of the pavement due to the widespread use of cement concrete. The quality of the pavement of cement concrete depends largely on the rational selection of its composition. This allows a significant increase in the durability of road pavement. The purpose of the research was: the development of recommendations for the rational selection of the composition of the road pavement material of cement concrete, aimed at upgrading longevity, and taking into account its frost resistance grade. According to the goal, the following tasks were developed: the analyses of the climatic zones in which the road network of the European Union is located; the development of a research plan, a selection of the response function and influence factors; the study of physico-mechanical and operational characteristics of the researched material of road pavement; on the basis of the obtained data, the calculation of the complex of experimental-statistical models, which describe the physico-mechanical and operational characteristics of the road pavement material; on the basis of experimental statistical models, a method was proposed for selecting the rational compositions of the cement concrete pavement road material depending on the conditions of its application. The results presented in the article can be used in engineering and scientific practice for the selection of road pavement from cement concrete for highways.

scholarly journals The Evaluation of Experimental Variables for Sustainable Virtual Road Safety Audits

2021 ◽  
Vol 13 (11) ◽  
pp. 5899
Author(s):  
Yeonsoo Jun ◽  
Juneyoung Park ◽  
Chunho Yeom
Keyword(s):  
Road Safety ◽  
Traffic Light ◽  
Scenario Development ◽  
Driving Simulators ◽  
Traffic Condition ◽  
The Road ◽  
Road Pavement ◽  
Net Promoter ◽  
Road Safety Audits ◽  
Road Marking

This paper evaluates experimental variables for virtual road safety audits (VRSAs) through practical experiments to promote sustainable road safety. VRSAs perform road safety audits using driving simulators (DSs), and all objects in the road environment cannot be experimental variables because of realistic constraints. Therefore, the study evaluates the likelihood of recommendation of VRSA experimental variables by comparing DSs experiments and field reviews to secure sustainable road safety conditions. The net promoter score results evaluated “Tunnel”, “Bridge”, “Underpass”, “Footbridge”, “Traffic island”, “Sign”, “Lane”, “Road marking”, “Traffic light”, “Median barrier”, “Road furniture”, and “Traffic condition” as recommended variables. On the contrary, the “Road pavement”, “Drainage”, “Lighting”, “Vehicle”, “Pedestrian”, “Bicycle”, “Accident”, and “Hazard event” variables were not recommended. The study can be used for decision making in VRSA scenario development as an initial effort to evaluate its experimental variables.

scholarly journals The Limestone as a Materials Combination of Base Course on the Road Pavement

2021 ◽  
Vol 1125 (1) ◽  
pp. 012019
Author(s):  
Yosef Cahyo Setianto Poernomo ◽  
Sigit Winarto ◽  
Zendy Bima Mahardana ◽  
Dwifi Aprillia Karisma ◽  
Rekso Ajiono
Keyword(s):  
The Road ◽  
Road Pavement ◽  
Base Course ◽  
On The Road

Use of soils and recycled industrial products treated with water glass in the road pavement base courses

2021 ◽  
Vol 2021 ◽  
pp. 86-93
Author(s):  
Anatolii Mudrychenko ◽  
◽  
Andrii Hrinchuk ◽  
Ivan Balashov ◽  
Sergey Illyasch ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Sodium Silicate ◽  
Water Glass ◽  
Water Solution ◽  
Road Construction ◽  
The Road ◽  
Road Pavement ◽  
Stone Materials ◽  
Pavement Base ◽  
Local Materials

Introduction. Growing volumes of road construction increase the need to expand and rationally use of raw materials. The need for stone materials can be solved through the wide spread using of local materials, recycled products of industry in the pavement base courses and decreasing the use of natural construction materials by replacing them with alternatives, including soils, slag materials that are metallurgical industry wastes. Experience of ferrous metallurgy slag usage has been accumulated in the road industry of Ukraine. Their usage makes it possible to extend the construction season, increases the strength and reliability of road structures due to their physical and mechanical properties, significantly reduces the road pavement energy consumption, simplifying the technology of works and the estimated cost of road construction. It was determined that the layers of pavement made from blast furnace slag have a high bearing capacity. Slag structures in 5–10 years of hardening are not inferior to, and in 10–20 years surpass cement structures on durability and deformation resistance. However, there is an urgent need to provide strength and open road traffic on the already built road section in a shortest possible term, so there is a need to accelerate the activation of the slow-setting binder. Therefore water glass (water solution of sodium silicate) is used.Purpose. The purpose of the work is to study the feasibility of using the soils and recycled industry products treated with water glass in the road pavement base courses.Materials and methods. Experimental tests of soils and blast furnace slags treated with water glass with different content of water solution of sodium silicate were performed.Results. The feasibility of using the asphalt concrete mixtures on the basis of soils and recycled products of industry treated with water glass in the pavement base courses is determined. Recommendations regarding technological parameters of preparation, transportation, laying and compaction of such mixes are given.Conclusions. Performed studies have shown that the physical and mechanical parameters of soils and blast furnace slags treated with water glass meet the requirements of current regulations of Ukraine. The advantages of use are noted, namely: the possibility of replacement of traditional stone materials by the local materials and recycled products of industry, reducing the transport component in the cost of construction. The obtained results indicate the feasibility of using the soils and recycled products of industry treated with water glass in the road construction.Keywords: soils, recycled products of industry, graded blast furnace slag, water solution of sodium silicate, water glass

scholarly journals Biogeochemical Regimes in Shallow Aquifers Reflect the Metabolic Coupling of the Elements Nitrogen, Sulfur, and Carbon

2018 ◽  
Vol 85 (5) ◽  
Author(s):  
Carl-Eric Wegner ◽  
Michael Gaspar ◽  
Patricia Geesink ◽  
Martina Herrmann ◽  
Manja Marz ◽  
...  
Keyword(s):  
Land Use ◽  
Organic Matter ◽  
Groundwater Flow ◽  
Inorganic Nitrogen ◽  
Sulfur Metabolism ◽  
Ammonium Oxidation ◽  
Metabolic Potential ◽  
Differentiation Potential ◽  
Near Surface ◽  
Monitoring Wells

ABSTRACTNear-surface groundwaters are prone to receive (in)organic matter input from their recharge areas and are known to harbor autotrophic microbial communities linked to nitrogen and sulfur metabolism. Here, we use multi-omic profiling to gain holistic insights into the turnover of inorganic nitrogen compounds, carbon fixation processes, and organic matter processing in groundwater. We sampled microbial biomass from two superimposed aquifers via monitoring wells that follow groundwater flow from its recharge area through differences in hydrogeochemical settings and land use. Functional profiling revealed that groundwater microbiomes are mainly driven by nitrogen (nitrification, denitrification, and ammonium oxidation [anammox]) and to a lesser extent sulfur cycling (sulfur oxidation and sulfate reduction), depending on local hydrochemical differences. Surprisingly, the differentiation potential of the groundwater microbiome surpasses that of hydrochemistry for individual monitoring wells. Being dominated by a few phyla (Bacteroidetes,Proteobacteria,Planctomycetes, andThaumarchaeota), the taxonomic profiling of groundwater metagenomes and metatranscriptomes revealed pronounced differences between merely present microbiome members and those actively participating in community gene expression and biogeochemical cycling. Unexpectedly, we observed a constitutive expression of carbohydrate-active enzymes encoded by different microbiome members, along with the groundwater flow path. The turnover of organic carbon apparently complements for lithoautotrophic carbon assimilation pathways mainly used by the groundwater microbiome depending on the availability of oxygen and inorganic electron donors, like ammonium.IMPORTANCEGroundwater is a key resource for drinking water production and irrigation. The interplay between geological setting, hydrochemistry, carbon storage, and groundwater microbiome ecosystem functioning is crucial for our understanding of these important ecosystem services. We targeted the encoded and expressed metabolic potential of groundwater microbiomes along an aquifer transect that diversifies in terms of hydrochemistry and land use. Our results showed that the groundwater microbiome has a higher spatial differentiation potential than does hydrochemistry.

scholarly journals Traffic Analysis and Pavement Technology as a Tool for Urban Noise Control

2015 ◽  
Vol 61 (4) ◽  
pp. 107-126 ◽  
Author(s):  
K. J. Kowalski ◽  
A. J. Brzeziński ◽  
J. B. Król ◽  
P. Radziszewski ◽  
Ł. Szymański
Keyword(s):  
Urban Space ◽  
Urban Traffic ◽  
Vehicle Speed ◽  
Noise Emission ◽  
Noise Barriers ◽  
Technical Improvement ◽  
Protection Measures ◽  
The Road ◽  
Road Pavement ◽  
Acoustic Conditions

Traffic related noise is currently considered as an environmental pollution. Paper presents results of multidirectional study attempting to serve urban traffic without the need to erect noise barriers interfering urban space. Initial concept of the road expansion included construction of 1000 m of noise barriers dividing city space. Improvement in the acoustic conditions after construction completion is possible due to the applied noise protection measures: vehicle speed limit, smooth of traffic flow, use of road pavement of reduced noise emission and the technical improvement of the tramway.

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