Alteration Features of Stones Applied in Underground Metro Stations

2010 ◽  
Vol 636-637 ◽  
pp. 1292-1299 ◽  
Author(s):  
Carlos Alves ◽  
Carlos Figueiredo ◽  
Paula Figueiredo ◽  
António Maurício ◽  
Luís Aires-Barros
Keyword(s):  
Field Study ◽  
Visual Inspection ◽  
Rock Type ◽  
Surface Irregularity ◽  
Non Invasive ◽  
Stone Materials ◽  
Complete Study ◽  
Stone Characteristics ◽  
Non Destructive ◽  
Selection Of

Several types of stones (igneous, sedimentary and metamorphic) are found applied in pavements, stairs and walls of the underground stations of the Lisbon Metropolitan System, Portugal. A field study based solely on non-destructive and non invasive visual inspection of these stations is presented, aiming to identify different transformations of applied stones and discuss its relation with the stone characteristics. This field study has pointed to relevant issues regarding durability of stone materials namely when used in pavements and stairs. The most striking aspect is the frequently marked variable behaviour of stones from a given rock type under the same use conditions, with heterogeneities and discontinuities that seem to cause irregularity from the early stages and further increase with time, having more accentuated consequences (in terms of intensity of surface irregularity) in some types of limestones. The observations collected could be relevant for the discussion of characteristics relevant for the quality control of these materials (namely at the quarry level), including the selection of stones for future substitutions. There is, therefore, the need for a more complete study comprising detailed petrographic studies and laboratory tests both from the applied stones and from the supplying quarries.

scholarly journals Diagnosis of the pathologies of a bridge, section: Champotón Bridge

2020 ◽  
pp. 20-28
Author(s):  
Francisco Javier Barrera-Lao ◽  
Román Alejandro Canul-Turriza ◽  
Andrea del Rosario Cruz-Y-Cruz ◽  
Julio Antonio Gutiérrez-González
Keyword(s):  
Field Study ◽  
Visual Inspection ◽  
Short Term ◽  
Photographic Record ◽  
Design Materials ◽  
Quantitative Descriptive ◽  
Object Of Study ◽  
Non Destructive

Objective: The present work seeks to expose the current pathological samples in the Champotón bridge, using its own methodology. Methods: It consists of an initial determination on the investigations in the structure and finishes. A non-destructive study of the property was carried out, through an eminently field study, in a qualitative, quantitative, descriptive and longitudinal way, first carrying out a visual inspection, preparing a photographic record, determining a diagnosis that would allow us to information on the object of study, an analysis of the deteriorations found, make a catalog of bridge factories to know the types of design materials, an own evaluation and finally, the most appropriate maintenance plans and proposed criteria were updated with their symbols correspondent. Conclusions. When carrying out a detailed visual inspection of the existing pathologies of the bridge, it is concluded that it requires constant routine maintenance and the pathologies found demand a short-term preventive rehabilitation, in order to prevent further progress and generate probable damages.

scholarly journals USING NON-DESTRUCTIVE TESTS FOR EVALUATING FLYOVER FOOTBRIDGE: CASE STUDY

2020 ◽  
Vol 1 (01) ◽  
pp. 23-39
Author(s):  
ALI SHUBBAR ◽  
Zainab Al-khafaji ◽  
Mohammed Nasr ◽  
Mayadah Falah
Keyword(s):  
Visual Inspection ◽  
Concrete Surface ◽  
Structural Components ◽  
Rebound Hammer ◽  
Rc Structures ◽  
Structural Part ◽  
Cell Test ◽  
Non Destructive ◽  
Selection Of

The concrete structures deterioration in the last few decades required effective methods for evaluating and maintaining the structure condition. Currently, assessing the performance and safety of reinforced concrete (RC) structures relies on routine-based visual inspection (VI). However, there are another non-destructive test (NDT) technique that can provide a more accurate assessment of the structures. Thus, in this study, a footbridge located in Liverpool, UK is chosen as a case study and has NDT techniques used for assessment. The main objective of this research is to determine the condition of structural bridge components and investigate its level of defect and deterioration using non-destructive tests. The methodologies involved are visual inspection, and NDT techniques include the rebound hammer, cover meter, Moisture Content & Depth of Carbonation Testing, Chloride Testing and Half Cell Test. The framework, when implemented with the best selection of NDT techniques, helps in determining the level of defect and deterioration of the structural bridge components and next recommendation regarding the condition of the bridge. The involved bridge structural components include column, deck, wall and staircase. Findings from the visual inspection show that there were many defects and deteriorations found at the structural bridge components, which includes crack, spalling, and delamination and rusting. Further, NDT techniques that were carried out at the selected bridge structural part shows that some of the components exhibited a moderate risk of corrosion and acceptable concrete surface quality. In general, further maintenance is needed specifically to some critical structural components of the bridge.

scholarly journals Raman spectroscopy enables phenotyping and assessment of nutrition values of plants: a review

Plant Methods ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
William Z. Payne ◽  
Dmitry Kurouski
Keyword(s):  
Raman Spectroscopy ◽  
Abiotic Stresses ◽  
Molecular Techniques ◽  
Plant Diseases ◽  
Label Free ◽  
Breeding Programs ◽  
Non Invasive ◽  
Nutrition Value ◽  
Non Destructive ◽  
Selection Of

AbstractOur civilization has to enhance food production to feed world’s expected population of 9.7 billion by 2050. These food demands can be met by implementation of innovative technologies in agriculture. This transformative agricultural concept, also known as digital farming, aims to maximize the crop yield without an increase in the field footprint while simultaneously minimizing environmental impact of farming. There is a growing body of evidence that Raman spectroscopy, a non-invasive, non-destructive, and laser-based analytical approach, can be used to: (i) detect plant diseases, (ii) abiotic stresses, and (iii) enable label-free phenotyping and digital selection of plants in breeding programs. In this review, we critically discuss the most recent reports on the use of Raman spectroscopy for confirmatory identification of plant species and their varieties, as well as Raman-based analysis of the nutrition value of seeds. We show that high selectivity and specificity of Raman makes this technique ideal for optical surveillance of fields, which can be used to improve agriculture around the world. We also discuss potential advances in synergetic use of RS and already established imaging and molecular techniques. This combinatorial approach can be used to reduce associated time and cost, as well as enhance the accuracy of diagnostics of biotic and abiotic stresses.

scholarly journals Field study on non-invasive and non-destructive condition assessment for asbestos cement pipelines by time-domain fluid transient analysis

2016 ◽  
Vol 15 (1) ◽  
pp. 113-124 ◽  
Author(s):  
Jinzhe Gong ◽  
Martin Lambert ◽  
Aaron Zecchin ◽  
Angus Simpson ◽  
Nicole Arbon ◽  
...  
Keyword(s):  
Field Study ◽  
Time Domain ◽  
Transient Analysis ◽  
Condition Assessment ◽  
Non Invasive ◽  
Fluid Transient ◽  
Asbestos Cement ◽  
Non Destructive

In search of the camp of the IV Scythian legion near ancient Artaxata: research at Pokr Vedi 2015–2018

2020 ◽  
pp. 409-432
Author(s):  
Oskar Kubrak ◽  
Paulina Kubrak ◽  
Mkrtich H. Zardaryan
Keyword(s):  
Electrical Resistivity ◽  
Aerial Photography ◽  
Magnetic Measurements ◽  
Roman Army ◽  
Field Surveys ◽  
Non Invasive ◽  
Southern Border ◽  
Building Activities ◽  
Geophysical Measurements ◽  
Selection Of

During the last years of Emperor Trajan’s reign, the Legio IV Scythica was stationed in the capital of Armenia at that time, Artaxata. It had made its way there within the scope of the Roman campaign against the Parthians. Its presence was immortalised on stamped rooftiles, bricks and a monumental inscription discovered by the southern border of the present-day village of Pokr Vedi. The inscription carved into limestone confirms the building activities of the Roman army. Similar inscriptions were frequently placed on the gates and most important buildings in legionary camps. Polish and Armenian archaeologists undertook a joint search for the supposed camp of the Fourth Scythian Legion in the vicinity of the present-day village of Pokr Vedi, where the above-mentioned construction inscription had been found. The field surveys conducted within the framework of the Pokr Vedi Project were mainly of a non-invasive character. The following were applied: surface prospection, aerial photography, interviews with the inhabitants, scanning of part of the terrain and geophysical measurements done using two methods: electrical resistivity and magnetic measurements. The accumulated data enabled the selection of sites in which survey trenches were located

scholarly journals Non-Invasive Testing of Physical Systems Using Topological Sensitivity

2021 ◽  
Vol 11 (3) ◽  
pp. 1341
Author(s):  
María Higuera ◽  
José M. Perales ◽  
María-Luisa Rapún ◽  
José M. Vega
Keyword(s):  
Lamb Waves ◽  
General Purpose ◽  
Mathematical Tool ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Topological Sensitivity ◽  
Physical Systems ◽  
Non Invasive ◽  
Active Infrared Thermography ◽  
Non Destructive

A review of available results on non-destructive testing of physical systems, using the concept of topological sensitivity, is presented. This mathematical tool estimates the sensitivity of a set of measurements in some given sensors, distributed along the system, to defects/flaws that produce a degradation of the system. Such degradation manifests itself on the properties of the system. The good performance of this general purpose post-processing method is reviewed and illustrated in some applications involving non-destructive testing. These applications include structural health monitoring, considering both elastodynamic ultrasonic guided Lamb waves and active infrared thermography. Related methods can also be used in other fields, such as diagnosis/prognosis of engineering devices, which is also considered.

scholarly journals Prevalence and Photobiology of Photosynthetic Dinoflagellate Endosymbionts in the Nudibranch Berghia stephanieae

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2200
Author(s):  
Ruben X. G. Silva ◽  
Paulo Cartaxana ◽  
Ricardo Calado
Keyword(s):  
Food Deprivation ◽  
Photosynthetic Efficiency ◽  
Rapid Decrease ◽  
Complete Loss ◽  
Symbiotic Association ◽  
Non Invasive ◽  
Sea Slugs ◽  
Non Destructive ◽  
Over Time

Berghia stephanieae is a stenophagous sea slug that preys upon glass anemones, such as Exaiptasia diaphana. Glass anemones host photosynthetic dinoflagellate endosymbionts that sea slugs ingest when consuming E. diaphana. However, the prevalence of these photosynthetic dinoflagellate endosymbionts in sea slugs appears to be short-lived, particularly if B.stephanieae is deprived of prey that host these microalgae (e.g., during bleaching events impacting glass anemones). In the present study, we investigated this scenario, along with food deprivation, and validated the use of a non-invasive and non-destructive approach employing chlorophyll fluorescence as a proxy to monitor the persistence of the association between sea slugs and endosymbiotic photosynthetic dinoflagellates acquired through the consumption of glass anemones. Berghia stephanieae deprived of a trophic source hosting photosynthetic dinoflagellate endosymbionts (e.g., through food deprivation or by feeding on bleached E. diaphana) showed a rapid decrease in minimum fluorescence (Fo) and photosynthetic efficiency (Fv/Fm) when compared to sea slugs fed with symbiotic anemones. A complete loss of endosymbionts was observed within 8 days, confirming that no true symbiotic association was established. The present work opens a new window of opportunity to rapidly monitor in vivo and over time the prevalence of associations between sea slugs and photosynthetic dinoflagellate endosymbionts, particularly during bleaching events that prevent sea slugs from incorporating new microalgae through trophic interactions.

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