In Situ Advanced Diagnostics and Inspection by Non-destructive Techniques and UAV as Input to Numerical Model and Structural Analysis - Case Study

2019 ◽  
pp. 359-371
Author(s):  
Vlatka Rajčić ◽  
Mislav Stepinac ◽  
Jure Barbalić
Keyword(s):  
Structural Analysis ◽  
Numerical Model ◽  
Non Destructive ◽  
Non Destructive Techniques

scholarly journals Effects of Infills in the Seismic Performance of an RC Factory Building in Pakistan

Buildings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 276
Author(s):  
Nisar Ali Khan ◽  
Giorgio Monti ◽  
Camillo Nuti ◽  
Marco Vailati
Keyword(s):  
Numerical Model ◽  
Construction Materials ◽  
Building Codes ◽  
Construction Technique ◽  
Infill Walls ◽  
Mortar Strength ◽  
Materials Used ◽  
Seismic Response Of Buildings

Infilled reinforced concrete (IRC) frames are a very common construction typology, not only in developing countries such as Pakistan but also in southern Europe and Western countries, due to their ease of construction and less technical skills required for the construction. Their performance during past earthquakes has been in some cases satisfactory and in other cases inadequate. Significant effort has been made among researchers to improve such performance, but few have highlighted the influence of construction materials used in the infill walls. In some building codes, infills are still considered as non-structural elements, both in the design of new buildings and, sometimes, in the assessment of existing buildings. This is mainly due to some difficulties in modeling their mechanical behavior and also the large variety of typologies, which are difficult to categorize. Some building codes, for example, Eurocode, already address the influence of infill walls in design, but there is still a lack of homogeneity among different codes. For example, the Pakistan building code (PBC) does not address infills, despite being a common construction technique in the country. Past earthquake survey records show that construction materials and infill types significantly affect the seismic response of buildings, thus highlighting the importance of investigating such parameters. This is the object of this work, where a numerical model for infill walls is introduced, which aims at predicting their failure mode, as a function of some essential parameters, such as the friction coefficient between mortar and brick surface and mortar strength, usually disregarded in previous models. A comprehensive case study is presented of a three-story IRC frame located in the city of Mirpur, Pakistan, hit by an earthquake of magnitude 5.9 on 24 September 2019. The results obtained from the numerical model show good agreement with the damage patterns observed in situ, thus highlighting the importance of correctly modeling the infill walls when seismically designing or assessing Pakistani buildings that make use of this technology.

Non-Destructive Tests and Bending Tests on Chestnut Structural Timber

2013 ◽  
Vol 778 ◽  
pp. 167-174 ◽  
Author(s):  
Beatrice Faggiano ◽  
Maria Rosaria Grippa ◽  
Bruno Calderoni
Keyword(s):  
Research Study ◽  
Timber Structures ◽  
Structural Elements ◽  
Bending Tests ◽  
Experimental Activity ◽  
Collapse Mechanisms ◽  
Regression Approach ◽  
Non Destructive ◽  
Non Destructive Techniques

In the context of a more wide research study for in situ mechanical identification of ancient timber structures by non-destructive techniques, the paper illustrates the experimental activity developed on structural elements made of old chestnut timber, 4x4x76 cm size: 24 squared specimens were extracted by six elements in actual dimensions, already used in a previous tests campaign. Non-destructive (ND: hygrometric, sclerometric and resistographic) and destructive (D: bending) tests were performed, the latter according to UNI EN 408 (2004) standard, in order to assess the mechanical properties and the collapse mechanisms of chestnut timber. Data gathered are presented in detail and, NDT-DT correlations, obtained through a linear regression approach, are provided to predict wood density, strength and modulus of elasticity of the tested members.

scholarly journals Conservation through knowledge: the case study of Parma Botanic Garden

2021 ◽  
Vol 1203 (2) ◽  
pp. 022047
Author(s):  
Lia Ferrari
Keyword(s):  
18Th Century ◽  
Existing Buildings ◽  
Botanic Garden ◽  
Complex Process ◽  
Critical Interpretation ◽  
Object Material ◽  
The University ◽  
Non Destructive

Abstract In the restoration field it is well known that the preservation of cultural heritage stands on a deep comprehension of the architectural object, material expression of a complex system made of cultural, technological, historical, social and economic issues. The knowledge of such meaningful structures requires the identification of both typological features and peculiar characteristics, within an interactive dialogue between contributions from different disciplines. Thus, the study of existing buildings is a complex process that needs to be planned: that means conceived, organized and realized with a critical method. The paper aims to show an example of this approach by presenting the knowledge path followed for the analysis of the Botanic Garden in Parma, Italy. This green area is located in the south of the city and hosts several buildings including the school of botany and the elegant greenhouse, built at the end of the 18th century. Recently, the restoration of the architectural complex has been proposed, aiming at its valorisation. The design process was supported by the studies and the analysis of the existing buildings carried out by the research group in Restoration of the University of Parma. In the specific, the constructive phases have been investigated through historical archive researches whereas the current structural systems have been studied through the geometric survey. Moreover, in-situ inspections allowed to define materials, deepening the knowledge of structural elements and their state of conservation. Finally, the survey of the crack pattern and decay allows to highlight vulnerabilities and mechanisms of collapse. In this way, it has been possible to understand the architectural structure thanks to the comparison between all data collected. On the other hand, in order to respect the historical construction, these analyses are required to reach a satisfying level of detail with the minimum action on the material construction, preferring non-destructive investigations. This approach entails assumptions and uncertainties that could be managed thanks to a critical interpretation of the results. Thus, the case study of Parma Botanic Garden shows the importance of planning the knowledge path with awareness in order to progressively deepen the comprehension with an interactive dialogue between the architectural object and the restoration issue.

scholarly journals Instructional Media in the XV Century (A Case Study of Widodaren, Gerba, and Pasrujambe Inscriptions)

2020 ◽  
Vol 40 (1) ◽  
pp. 121-142
Author(s):  
Raka Rakai Hino
Keyword(s):  
Structural Analysis ◽  
Literature Review ◽  
Learning Process ◽  
Teaching And Learning ◽  
Qualitative Method ◽  
Moral Values ◽  
Tool Support ◽  
Instructional Media

This study was aimed at analyzing and interpreting the instructional media existing in the classical period of the Hindu - Buddhist kingdoms. The object of the study was inscriptions found on the Semeru Slope, inclduing Widodaren, Pasrujambe, and Gerba. This study employed a qualitative method with an archeological-historical framework. The data was collected through a literature review and in-situ research of the inscriptions. The collected data was analyzed using a structural analysis in the forms of transliteration of the contents and meaning written at the inscriptions. The study found that there is evidence of the use of instructional media in teaching process. This finding is also supported by the Nāgarakṛtâgama and Bujaņga Manik manuscripts which narrate educational and moral values as one of the characteristics of instructional media. In addition, the instructional media serve as a tool support the teaching and learning process at that time.

scholarly journals Research on the Organic Binders in Archaeological Wall Paintings

2021 ◽  
Vol 11 (19) ◽  
pp. 9179
Author(s):  
Antonella Casoli
Keyword(s):  
Chemical Composition ◽  
Organic Material ◽  
Wall Painting ◽  
Wall Paintings ◽  
Chromatographic Techniques ◽  
Invasive Techniques ◽  
Non Destructive ◽  
Potential Tool ◽  
Non Destructive Techniques

Wall painting realized using organic binders is the oldest form of parietal painting and precedes the birth of the affresco by about 20,000 years. This paper reports the results obtained from the main studies in the field of archaeological wall paintings. The attention was paid to the study of organic binders used for the application of the color, as well as on the instrumental techniques chosen to obtain such information. Different techniques can be used for the study of organic material in archeological paintings: non-destructive techniques, which can be applied directly in situ without sampling, and laboratory micro-invasive techniques for a more in-depth characterization. Among these, the chromatographic techniques represent a potential tool to acquire as much information as possible about chemical composition of binders.

scholarly journals Sonic and Impact Test for Structural Assessment of Historical Masonry

2019 ◽  
Vol 9 (23) ◽  
pp. 5148 ◽  
Author(s):  
Alessandro Grazzini
Keyword(s):  
Impact Test ◽  
Structural Parameters ◽  
Historical Masonry ◽  
2016 Amatrice Earthquake ◽  
The Impact ◽  
Santa Maria ◽  
Non Destructive ◽  
Non Destructive Techniques

Diagnostics is a very important tool of knowledge in the field of historical buildings. In particular, non-destructive techniques allow to deepen the study of the mechanical characteristics of the historical walls without compromising the artistic value of the monumental building. A case study of the use of sonic and impact tests was described, performed using the same instrumented hammer, for the characterization of the masonry walls at the Sanctuary of Santa Maria delle Grazie at Varoni, one of the churches damaged in the 2016 Amatrice earthquake. Sonic tests showed the presence of a discontinous masonry texture, as well as confirming the ineffectiveness of the strengthening work made by injections of lime mortar. The impact test allowed us to obtain the elastic modulus of the omogeneous stones of the masonry. The results obtained from the non-destructive techniques were confirmed by the flat jacks test carried out on the building, confirming the great potential of the non-destructive diagnostics suitable for analyzing important structural parameters without affecting the preservation of historical masonry structures.

Health Monitoring of Medieval Masonry Towers by an Acoustic Emission Approach

2019 ◽  
Vol 817 ◽  
pp. 586-593
Author(s):  
Giuseppe Lacidogna ◽  
Gianni Niccolini ◽  
Alberto Carpinteri
Keyword(s):  
Acoustic Emission ◽  
Health Monitoring ◽  
Masonry Wall ◽  
Masonry Buildings ◽  
Earthquake Occurrence ◽  
Structural Element ◽  
Natural Time ◽  
Non Destructive

Non-destructive tests were performed to assess cracking evolution in two medieval masonry buildings, Sineo and Asinelli towers rising respectively in the Cities of Alba and Bologna, in Italy. As regards the case study of Alba, in situ compressive flat-jack tests on small-sized elements of the tower were conducted in conjunction with acoustic emission (AE) monitoring. At the same time, crack patterns taking place in large volumes of the tower were likewise monitored through the AE technique.As for the case study of Bologna, a masonry wall of the Asinelli tower was monitored during a period of intense seismic activity. The observed correlation between the AE activity in the monitored structural element and local earthquakes points out a significant dependence of deterioration processes in the tower on the action of nearby earthquakes.In both cases, the trends of two evolutionary parameters, the b-value and the natural time (NT) variance κ1, were derived from the AE time series to identify the approach of the monitored structures to a critical state in relation to the earthquake occurrence.

scholarly journals Integrated Investigation of Built Heritage Monuments: The Case Study of Paphos Harbour Castle, Cyprus

Heritage ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 1-14
Author(s):  
Vasiliki Lysandrou ◽  
Athos Agapiou ◽  
Manolis Ioannides ◽  
Nikolaos Kantiranis ◽  
Eleftherios Charalambous ◽  
...  
Keyword(s):  
Image Processing ◽  
Construction Materials ◽  
Masonry Walls ◽  
Built Heritage ◽  
Processing Techniques ◽  
Small Parts ◽  
Non Destructive ◽  
Non Destructive Techniques ◽  
Destructive Methods

The state of preservation of built heritage monuments is often evaluated by means of several destructive techniques, which are mainly focused on the analysis of small parts of the monuments’ construction materials. The necessary sampling for the accomplishment of these destructive analyses is usually restricted to confined parts of a monument, since monuments are usually under protective legislation, and therefore only indicative of larger areas. Current research attempts to enhance the results of provided by destructive methods, using non-destructive image processing techniques. Towards this end, the potential use of image processing based on rectified images is examined, along with material sampling and laboratory analyses as part of a multi-disciplinary methodology for the investigation of Paphos (Cyprus) Harbour Castle. This approach has been adopted in order to map the degradation patterns observed on the monument’s masonry walls, minimizing destructive methods and attempting to visualize the results of the monument as a whole. The combination of both analytical and non-destructive techniques resulted in the acquisition of large amounts of information, permitting the evaluation of applied non-destructive techniques for the study of the deterioration present on a monument’s external surfaces. This approach led to the assessment of the overall state of preservation of the masonry walls of the structure in an extended scale covering all external façades in a semi-automatic way.

scholarly journals Decay detection in an ancient column with combined close-range photogrammetry (CRP) and ultrasonic tomography.

2021 ◽  
Author(s):  
Giuseppe Casula ◽  
Silvana Fais ◽  
Francesco Cuccuru ◽  
Maria Giovanna Bianchi ◽  
Paola Ligas ◽  
...  
Keyword(s):  
High Resolution ◽  
Diagnostic Process ◽  
Ultrasonic Tomography ◽  
Invasive Approach ◽  
Non Invasive ◽  
Close Range Photogrammetry ◽  
Close Range ◽  
Non Destructive ◽  
Non Destructive Techniques

<p>The diagnosis of the conservation state of monumental structures from constraints to the spatial distribution of their physical properties on shallow and inner materials represents one of the key objectives in the application of non-invasive techniques. <em>In situ</em>, CRP and 3D ultrasonic tomography can provide an effective coverage of stone materials in space and time. The intrinsic characteristics of the materials that make up a monumental structure and affect the two properties (i.e., reflectivity, longitudinal velocity) through the above methods substantially differ. Consequently, the content of their information is mainly complementary rather than redundant.</p><p>In this study we present the integrated application of different non-destructive techniques i.e., Close Range Photogrammetry (CRP), and low frequency (24 KHz) ultrasonic tomography complemented by petrographycal analysis based essentially on Optical Microscopy (OM). This integrated methodology has been applied to a Carrara marble column of the <em>Basilica of San Saturnino</em>, in Byzantine-Proto-Romanesque style, which is part of the Paleo Christian complex of the V-VI century. This complex also includes the adjacent Christian necropolis in the square of <em>San Cosimo</em> in the city of Cagliari, Sardinia, Italy. The column under study is made of bare material dating back probably to the first century A.D., it was subjected to various traumas due to disassembly and transport to the site, including damage caused by the close blast of a WWII fragmentation bomb.</p><p>High resolution 3D modelling of the studied artifact was computed starting from the integration of proximal sensing techniques such as CRP based on Structure from Motion (SfM), with which information about the geometrical anomalies and reflectivity of the investigated marble column surface was obtained. On the other hand, the inner parts of the studied body were successfully inspected in a non-invasive way by computing the velocity pattern of the ultrasonic signal through the investigated materials using 3D ultrasonic tomography. This technique gives information on the elastic properties of the material related with mechanical properties and a number of factors, such as presence of fractures, voids, and flaws. Extracting information on such factors from the elastic wave velocity using 3D tomography provides a non-invasive approach to analyse the property changes of the inner material of the ancient column. The integrated application of <em>in situ</em> CRP and ultrasonic techniques provides a full 3D high resolution model of the investigated artifact. This model enhanced by the knowledge of the petrographic characteristics of the materials, improves the diagnostic process and affords reliable information on the state of conservation of the materials used in the construction processes of the studied monumental structure. The integrated use of the non-destructive techniques described above also provides suitable data for a possible restoration and future preservation.</p><p><strong> </strong></p><p><strong>Acknowledgments: </strong>This work was partially supported by FIR (Fondi integrativi per la Ricerca) funded by the University of Cagliari (Italy). The authors would also like to thank the Ministero dei Beni e delle Attività Culturali. Polo Museale della Sardegna and Arch. Alessandro Sitzia for their kind permission to work on the <em>San Saturnino Basilica</em>.</p>

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