bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bending-induced local buckling during offshore installation of multi-layered FRP pipelines
Authors: Pavlou D , Adasooriya N D 
Published: November 2021

Abstract
In the last two decades FRP pipelines have attracted the attention of the oil industry because of their high strength, excellent fatigue performance and low specific weight. On the other hand, the final cost of installation of FRP pipelines is comparable to the cost of carbon steel ones. Therefore, their implementation in offshore applications seems to be advantageous. During offshore installation, the curvatures of the pipes during the S-lay or J-lay installation processes cause high bending stresses and risk for bending-induced local buckling. Since the pipe wall is multi-layered and the laminae are anisotropic, the calculation of critical bending moments is difficult. In the present work, an analytical solution of critical bending moments for bending-induced local buckling is provided. The proposed method uses the classical lamination theory of multi-layered anisotropic materials and Flügge’s assumption for local buckling analysis of pipelines. Results for E-Glass fiber reinforced polymeric pipelines are provided and discussed.
Fatigue life analysis of wheel-rail contacts at railway turnouts using finite element modelling approach.
Authors: Jelila Y D , Lemu H G , Pamuła W , Sirata G G. 
Published: November 2021

Abstract
The article deals with wheel-rail contact analysis at railway turnout using a finite element modelling approach. The focus is understanding the wheel-rail contact problems and finding the means of reducing these problems at railway turnouts. The main aim of the work reported in this article is to analyse fatigue life and simulate the wheel-rail contact problems for a repeated wheel loading cycle by considering the effect of normal and tangential contact force impact under different vehicle loading conditions. The study investigates the impact of tangential contact force generated due to different-angled shapes of the turnout and aims to reveal how it affects the life of contacting surfaces. The obtained results show that the maximum von-Mises equivalent alternating stress, maximal fatigue sensitivity, and maximum hysteresis loop stresses were observed under tangential contact force. These maximum stresses and hysteresis loops are responsible for rolling contact fatigue damage, and excessive deformation of the wheel-rail contact surface. At a constant rotational velocity, the tangential contact force has a significant impact on the fatigue life cycle and wheel-rail material subjected to fatigue damage at lower cycles compared to the normal contact force. The finite element modelling analysis result indicated that the contact damages and structural integrity of the wheel-rail contact surface are highly dependent on contact force type and can be affected by the track geometry parameters.
Solutions for monitoring the technical condition of metal structures and pipelines located at an altitude
Authors: Pshenin V V , Borisov A V , Menshikov S O 
Published: November 2021

Abstract
Periodic monitoring of the technical condition of metal constructions and pipelines at an altitude is an important part of their safe operation. For this purpose, as a rule, drones or methods of industrial climbing are used. In this research we propose a method of robotic inspection of such structures, which will substantially reduce the costs of maintenance work at an altitude and increase their level of safety. The main scientific interest is the creation of a universal kinematics adjusted to different obstacles not only on the pipelines but also on the metal constructions. In the course of the works there was conducted a fundamentally different experience in the mounting of supporting structures and metal constructions. The received knowledge was systematized in an album of the obstacles, on the basis of which the kinematics of the robotic device was modified.
A simple machine learning based framework for processing the inline inspection data of subsea pipelines
Authors: Liu Z , Dahl S S , Larsen E S , Yang Z 
Published: November 2021

Abstract
This paper presents a simple machine learning based framework for diagnosing the inline inspection data (ILI) of subsea pipelines. ILI data are obtained by intelligent pigging devices operating along subsea pipelines. The wall thickness (WT) and standoff distance (SO) are collected by the sensors installed on the pigging, which are normally in the format of 2D arrays. There are many uncertainties for the ILI data collected from the offshore survey. An attempt was made to apply the machine learning method to diagnose the uncertainties. A convolutional neural network (CNN) is used, the ILI data are discretized and processed in 64x64 grid size. Fabricated training datasets were made for training the machine learning model since the ground truth information (actual corroded wall thickness) is hardly known in this case. The trained model was successfully. It is demonstrated that certain corrosion patterns have been recognized by the trained model. Comparisons were performed between the new method and traditional methods with case studies on real ILI data. The validity of the methodology was discussed.
Experimental investigation on the mechanical and chemical properties of lightweight aggregate concrete with CO2 curing
Authors: Wang Z , Dehestani S , Kakay S , Sha Y 
Published: November 2021

Abstract
In the cement and concrete industry, enormous amounts of Carbon Dioxide (CO2) are emitted during their production processes. Carbon dioxide emission significantly contributes to the global climate change, which has been one of the biggest challenges of our times. Some novel solutions have been proposed for CO2 capture and storage, as well as reducing CO2 emission in concrete production. Carbonation curing is an effective alternative for conventional water curing for concrete. It can store CO2 in the hardened concrete and meanwhile improve early mechanical properties of concrete. Partial replacement of cement with fly ash shows environmental benefits, such as reducing greenhouse gas emissions and industrial waste destined for landfills. There has been some previous research studying on the effect of carbonation curing on normal Portland concrete in the past decade. Nevertheless, few studies have focused on the CO2 curing for lightweight aggregate concrete (LWAC). In this paper, the influence of early carbonation curing on LWAC is studied. LWAC specimens with two different water-to-cement ratios are cast and cured for a series of experimental investigations. The mechanical and chemical properties including the 1-day compressive strength, 28-day compressive strength, flexural strength, CO2 uptake, heat development, and pH level are investigated. Specimens with ordinary Portland cement are also tested as references in terms of compressive strength and CO2 uptake.
Use of digital technology to follow the consequences of a warming Arctic climate
Authors: Hætta Myrmel L B , Gudmestad O T 
Published: November 2021

Abstract
The rapid warming climate is causing the Arctic ice to retreat and the permafrost to melt. These visible manifestations of the ongoing climate change are few of many environmental and societal changes that take place in the Arctic. The acceleration of digitalization and implementation of digital technology bring new opportunities to follow the consequences of the warmer arctic climate, but also introduces new challenges in this region as the dependency on the digital technology increases. This paper focuses on the cyber ecosystem and discusses digital technology available for monitoring the consequences of a warming Arctic and its impact on Critical Infrastructure (CI) in Norway, such as communication networks, electric power transfer systems, water and wastewater, transportation infrastructure, oil and gas infrastructure. The need for reliable satellite communications is emphasized.
Problems of development and economic evaluation of production of natural hydrocarbons on the offshore of the Arctic Seas
Authors: Bogatkina Y , Eremin N , Sardanashvili O 
Published: November 2021

Abstract
The purpose of this article is to substantiate taxation models that have contributed to an increase in the efficiency of offshore oil and gas fields that are at the stage of mature development in the harsh Arctic conditions. The development of Arctic fields under the current tax regime is on the verge of profitability. As an experiment, an economic assessment of the main economic indicators of the option for the development of the Prirazlomnoye field was carried out, taking into account various tax mechanisms used to assess the effectiveness of the development of offshore oil and gas fields. The calculation results showed that the application of the tax regime in force in Russia makes the development of the Prirazlomnoye field efficient, but with a relatively low profitability for the license holder. As an alternative, the tax mechanisms laid down in the production sharing agreements in China and Russia were used, which showed a high economic effect with a low level of risk. It can be concluded that the use of taxation models, which are similar in nature to a production sharing agreement, significantly increases the efficiency of the Prirazlomnoye field development, and can bring greater financial benefits to the license holder in comparison with the current tax regime in the Russian Federation.
Computer technologies to determine offshore facilities suitable for the climatic conditions
Authors: Shatrovskii I , Zolotukhin A 
Published: November 2021

Abstract
This article provides an overview of computer technologies and an analysis of their application possibilities to determine the quantitative and qualitative composition of the facilities for the development of offshore oil and gas fields for given climatic conditions. The first question covered in the article is how to form a data set including the information about offshore fields development conditions. The author gives examples of using the Python programming language, NumPy, Tesseract and OpenCV libraries for that purpose. For each designated variable, a test program code was done to obtain the required value. Another question, which is given in the article, is how to analyze the obtained results and determine which offshore facilities are best suited for certain climatic conditions. For this purpose, a deep neural network of forwarding propagation was created with the help of Keras, TensorFlow and Scikit-learn Python libraries. The network performance was tested on a sample of a small size, the results were analyzed, and future research tasks were defined.
Transformation of the energy sector in the Arctic in the context of sustainable development of the region
Authors: Fedorova V A , Kadzhaeva E T , Vovkodav K V 
Published: November 2021

Abstract
The Arctic is the northernmost region of our planet, including the outskirts of the continents of Eurasia and North America, as well as the corresponding islands and archipelagos, the Arctic Ocean and parts of the Atlantic and Pacific oceans. Despite the still existing discrepancy in the concept of the boundaries of the Arctic region, all researchers agree in one opinion: this region is most sensitive to the climate change, and the consequences may be irreversible. As a part of the commitments on sustainable development undertaken by Russia and taking into account the importance and special status of the Arctic region, it seems necessary to consider the possibility of transforming the energy sector of the Arctic as one of the main sources of emissions of pollutants and CO2 in the region. The combination of energy sources proposed in the article - natural gas and renewable energy sources - is the cleanest and most environmentally friendly, and a hybrid energy system based on this alliance is the most sustainable and allows to use advantages of proposed energy sources, hedging each other's limitations. Proposed hybrid system could contribute to the development of the region and the well-being of its population and the environment.
Deep learning based restoration of lost sections in Micro-CT core plugs
Authors: Arsenyev-Obraztsov S S , Plusch G O 
Published: November 2021

Abstract
Lack of petrophysical information is critical for reservoirs development composed of poorly consolidated rocks or for zones bearing wells with core damaged by improper coring operations. The restoration complexity of the digital-core lost sections is associated with the need to consider an enormous amount of data from the existing core image and the necessity to include lithological expert knowledge. That makes deep learning methods a natural choice for solving such problems. We proposed, examined, and compared several deep learning methods convenient for analyzing micro-computed tomography digital core data. It was done under the most simplistic problem statement when the destroyed part (a set of slices) is completely lost. Here, we present the results of comparison interpolation/extrapolation procedures under proposed quality metrics. We discover that the variational autoencoder method can be trained to extract some petrophysical parameters from the digital core plug in an unsupervised manner.
Performance of sodium lignosulfonate as thickening additive in compositions for matrix acidizing of bottom hole zone
Authors: Sentemov A A 
Published: November 2021

Abstract
The work considers one of the promising directions for optimizing matrix acidizing using sodium lignosulfonate as a thickening agent. The mechanism of the interaction of acid solutions containing lignosulfonate with carbonate reservoirs is described. The use of sodium lignosulfonate in acid solutions solves several problems. Slowing the reaction rate allows the acid solution penetrate deeper into the formation, with maintaining the HCl concentration. The increased viscosity of the compositions increases the sweep efficiency of the bottomhole zone in the process of matrix acidizing. These two aspects increase the efficiency of matrix acidizing and the permeability of the bottomhole zone. In the course of this work, the chemical reaction rate of sodium lignosulfonate and hydrochloric acid solutions with carbonate core samples were evaluated. Sodium lignosulfonate in an acid solution reduces the dissolution rate of carbonate samples. It is assumed that slowing down the reaction rate allows the acid solution to form long high permeability channels which increases the efficiency of acidizing.
The effect of volatile organic acids and CO2 on the corrosion rate of carbon steel from a Top-of-Line-Corrosion (TLC) perspective
Authors: Gjertsen S B , Palencsar A , Seiersten M , Hemmingsen T H 
Published: November 2021

Abstract
Models for predicting top-of-line corrosion (TLC) rates on carbon steels are important tools for cost-effectively designing and operating natural gas transportation pipelines. The work presented in this paper is aimed to investigate how the corrosion rates on carbon steel is affected by acids typically present in the transported pipeline fluids. This investigation may contribute to the development of improved models. In a series of experiments, the corrosion rate differences for pure CO2 (carbonic acid) corrosion and pure organic acid corrosion (acetic acid and formic acid) on X65 carbon steel were investigated at starting pH values; 4.5, 5.3, or 6.3. The experiments were conducted in deaerated low-salinity aqueous solutions at atmospheric pressure and temperature of 65 °C. The corrosion rates were evaluated from linear polarization resistance data as well as mass loss and released iron concentration. A correlation between lower pH values and increased corrosion rates was found for the organic acid experiments. However, the pH was not the most critical factor for the rates of carbon steel corrosion in these experiments. The experimental results showed that the type of acid species involved and the concentration of the undissociated acid in the solution influenced the corrosion rates considerably.
Failure prediction of reservoir pressure maintenance system at the Prirazlomnoye Arctic Offshore field
Authors: Kurchatov I M 
Published: November 2021

Abstract
Failures of reservoir pressure maintenance system at offshore facilities cause production losses and a significant increase in OPEX. Predicting failures of a water injection pump or its parts can highly improve the overall performance by promptly adjusting operating parameters to prevent failure occurrence or by scheduling maintenance to reduce unplanned repairs and to minimize downtime. This is particularly relevant for Arctic offshore projects, characterized by considerable logistical challenges and substantial environmental safety risks. The paper presents a data-analytic approach for failure prediction for the water injection pump operated at the ice-resistant GBS Prirazlomnaya. The study used pump failure history and field sensor data to predict the technical condition and identify a failed component in advance. An ARIMA model implemented in the R software environment was developed for the analysis. The results demonstrate that the approach works appropriately based on the generalized risk assessment and feedback from subject matter experts.
Effect of mechanical activation on the properties of Portland cement
Authors: Ravaszová S , Dvořák K 
Published: November 2021

Abstract

The paper deals with the mechanical activation of cement by grinding in a high-speed mill, and compares the parameters found with the commonly used grinding method in cement production, which uses grinding of cement by means of a ball mill. The aim is to verify the influence of the aging time of the ground material on the preservation of the mechanical activation effect and on the properties of the final product at different stages of hydration. It evaluates the physical-mechanical properties, the compressive and tensile strength after 1, 2, 7, 14 and 28 days, as well as the course of the hydration process. The evaluated results suggest the existence of mechanical activation, but this effect is very difficult to achieve and depends on many other factors.
Shotcrete using ternary binder made from coal combustion products: from lab tests to an application
Authors: Šmilauer Vít , Sovják Radoslav , Pešková Šárka , Šulc Rostislav , Škvára František , Šídlová Martina , Snop Roman , Rüžička Pavel 
Published: November 2021

Abstract
The paper presents a ternary binder development and its utilization in shotcrete. The binder is made from fluidized bed combustion (FBC) fly ash, siliceous fly ash, and Ca(OH)2 addition, now available under the name Sorfix. XRD and TGA identified ettringite and C-S-H as two main hydration products. In addition, thermodynamic modeling verified robustness in terms of space-filling capabilities when varying input oxide composition.
Since alkali-free accelerators produce mostly ettringite in Portland-based systems, a fraction of Portland cement was advantageously replaced with the ternary binder, forming early ettringite as well. Extensive testing led to 45% replacement of Portland cement, following J2 curve for early strength gain used commonly in shotcrete tunnel linings. The shotcrete was successfully tested in a mock-up experiment in a 2 m3 Prague served for the full-scale application, utilizing over 1000 tons of Sorfix and saving over 700 tons of CO2
Light autoclaved foam concrete with foam glass-based aggregate
Authors: Bibora P , Prachar V , Svitak O , Zavrelova R. 
Published: November 2021

Abstract
The presented research aims to develop new optimized composition of novel lightweight concrete with a very low bulk density. Low bulk density of developed lightweight concrete is achieved by using a combination of non-traditional lightweight artificial fillers, dispersed fibre reinforcement and pre-generated technical foam. The methodology of lightweight concrete test specimen production, based on technologies commonly applied for the production of lightweight concrete, foam concrete or autoclaved aerated concrete was also designed and verified. Not only the physical and mechanical parameters, but also the thermal insulation properties were verified on the produced test specimens of the developed lightweight concrete.
Impact performance of rubber reinforced concrete with waste steel fibres
Authors: Drdlova M , Bibora P , Prachar V 
Published: November 2021

Abstract
This study introduces cementitious composite with rubber granulate and waste steel fibres as a new material for construction industry with an enhanced energy absorption capability and impact toughness. Detailed research on physico-mechanical properties of high-performance concrete with waste steel fibres and partial replacement of the aggregates by rubber granulate was performed, with emphasis on impact energy absorption potential. Different aggregate replacement ratios (0–30% wt.) and fibre amount (0–3% wt.) were investigated. The influence of rubber sizes, rubber content and steel fibre content on the mechanical parameters of the rubberized concrete at both quasistatic and dynamic loads was evaluated and discussed. With increasing amount of rubber granulate, the concrete suffered from reduction of its mechanical parameters – compressive and flexural strength, however the energy dissipation capability showed rising trend. This study demonstrated the potential of rubberized concrete with waste steel fibres for use in structures with higher impact resistance requirements.
Lime-based mortars with various binder composition: characterization and freeze-thaw resistance assessment
Authors: Janotova D , Slizkova Z 
Published: November 2021

Abstract
The study focused on lime mortars with different lime binder types regarding the frost attack effects on their microstructure and mechanical characteristics. The performances of studied mortars in hardened state was significantly influenced by the amount of mixing water and by curing conditions. Inhomogeneous microstructure was observed inside the 360 days old specimens with dimensions 40 × 40 × 160 mm in the case of all lime mortars types. The different state of the binder hardening with respect to various distances from the specimen surface and the different behaviour of matured outer part and immature inner part of lime mortar specimens influenced performed tests and reflected in all results. After 10 and 20 freeze cycles, respectively, the compressive strength of all lime mortar specimens with the hydraulic binder component increased, indicating a beneficial effect of the water on the hydration previously unreacted hydraulic binders. On the other hand, the flexural strength of the frost-aged specimens decreased significantly, indicating the drastic procedure of the test performed concerning lime mortars characteristics, especially when the pure air lime binder was used. Improvement of the testing procedure especially for lime mortars, which are characterized by slow hardening, was recommended.
The effect of consolidation treatment on selected mechanical properties of sandstone
Authors: Gajdos E , Sperl M , Slizkova Z , Drdlova M 
Published: November 2021

Abstract
An investigation was made into selected mechanical properties of sandstone of Božanov mining site in Czechia using both natural specimens of the sandstone and specimens impregnated with consolidants – liquid products aimed at improving strength and durability of degraded stones. Experiments in three-point bending of notched and cracked specimens made it possible to determine (i) the quasi-static notch toughness as well as the fracture toughness of specimens when they were subjected to static loading, and (ii) the impact fracture toughness and total energy of fracture when specimens were subjected to impact loading. The results of the tests are presented and are discussed with a view to the effects of consolidants.