{"id":{"repo_id":"greece","oai_identifier":"oai:10442/1192"},"canonical_url":"https://search.dev.ndltd.org/etd/greece/oai:10442/1192","repository":{"repo_id":"greece","name":"Greek National Archive of PhD Theses","base_url":"https://phdtheses.ekt.gr/eadd_oai/request"},"display":{"title":"ΕΠΙΔΡΑΣΗ ΤΗΣ ΠΑΡΟΥΣΙΑΣ ΡΩΓΜΩΝ ΣΤΗΝ ΚΑΤΑΝΟΜΗ ΤΗΣ ΕΝΤΑΣΕΩΣ ΣΕ ΘΛΙΒΟΜΕΝΑ ΣΩΜΑΤΑ. ΕΦΑΡΜΟΓΕΣ ΣΤΗΝ ΠΕΡΙΟΧΗ ΤΗΣ ΒΡΑΧΟΜΗΧΑΝΙΚΗΣ","abstract":"THE CALCULATION OF THE STRESSES DEVELOPED ALONG THE CRACK FLANKS DUE TO COMPRESSION AND SHEARING IN THE FIRST TOPIC OF THIS THESIS . A CORRELATION MODEL HAS BEEN INTRODUCED IN ORDER TO CORRECT THE INCOMPATIBLE IN-PLANE DISPLACEMENTS, WHICH ARE PRODUCED BY THE SHEAR STRESSES. THE RESULT OF THIS CORRECTION IS, THE DEVELOPMENT OF AN ADDITIONAL COMPRESSION ALONG THE CRACK LIPS. THE EFFECT OF THESE STRESSES IS THE DEVELOPMENT OF A POSITIVE (TENSILE) KI-SIF AT THE CRACK TIPS.THIS SMALL, POSITIVE KI-SIF INSIDE AN OVERALL COMPRESSIVE STRESS FIELD IS CAUSING THE DEVIATION OF THE CRACK PROPAGATION UNDER COMPRESSION. IN THIS WAY THE PROPAGATED CRACK IN FOLLOWING A PATH TOWARDS THE COMPRESSIVE STRESS. THIS ASSUMPTION IS TESTED WITH EXPERIMENTS IN PLATES MADE BY PMMA, WITH SLITS AND CRACKS. IN ORDER TO EXAMINE THE TYPE OF THE STRESS FIELD AT THE TIPS OF THE PROPAGATED CRACKS, THE METHOD OF CAUSTICS HAS BEEN USED. THE METHOD WAS PREVIOUSLY TESTED IN A SERIES OF EXPERIMENTS ON MODELS WITH CRACKS AND SLITS UNDER COMPRESSION. THE EXPERIMENTAL RESULTS WERE IN AGREEMENT WITH THE ASSUMPTIONS MADE IN THE THEORETICAL PART OF THE DISSERTATION.","abstract_html":"THE CALCULATION OF THE STRESSES DEVELOPED ALONG THE CRACK FLANKS DUE TO COMPRESSION AND SHEARING IN THE FIRST TOPIC OF THIS THESIS . A CORRELATION MODEL HAS BEEN INTRODUCED IN ORDER TO CORRECT THE INCOMPATIBLE IN-PLANE DISPLACEMENTS, WHICH ARE PRODUCED BY THE SHEAR STRESSES. THE RESULT OF THIS CORRECTION IS, THE DEVELOPMENT OF AN ADDITIONAL COMPRESSION ALONG THE CRACK LIPS. THE EFFECT OF THESE STRESSES IS THE DEVELOPMENT OF A POSITIVE (TENSILE) KI-SIF AT THE CRACK TIPS.THIS SMALL, POSITIVE KI-SIF INSIDE AN OVERALL COMPRESSIVE STRESS FIELD IS CAUSING THE DEVIATION OF THE CRACK PROPAGATION UNDER COMPRESSION. IN THIS WAY THE PROPAGATED CRACK IN FOLLOWING A PATH TOWARDS THE COMPRESSIVE STRESS. THIS ASSUMPTION IS TESTED WITH EXPERIMENTS IN PLATES MADE BY PMMA, WITH SLITS AND CRACKS. IN ORDER TO EXAMINE THE TYPE OF THE STRESS FIELD AT THE TIPS OF THE PROPAGATED CRACKS, THE METHOD OF CAUSTICS HAS BEEN USED. THE METHOD WAS PREVIOUSLY TESTED IN A SERIES OF EXPERIMENTS ON MODELS WITH CRACKS AND SLITS UNDER COMPRESSION. THE EXPERIMENTAL RESULTS WERE IN AGREEMENT WITH THE ASSUMPTIONS MADE IN THE THEORETICAL PART OF THE DISSERTATION.","abstract_has_math":false,"creators":["Σακελλαρίου, Μιχαήλ"],"institution":"National Technical University of Athens (NTUA)","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1989,"date_issued":"1989","date_published":"1989","updated_at":"2026-07-24T02:24:46Z","subjects":["Brazilian test","Caustics","Compression","CRACK DEFORMATION","Crack propagation","FRACTURE INITIATION","Fracture mechanics","Friction","Shear","STICK-SLIP, BOUNDARY ELEMENT METHOD","ΒΡΑΖΙΛΙΑΝΗ ΔΟΚΙΜΗ","Διάδοση ρωγμής","Διάτμηση","ΕΝΑΡΞΗ ΘΡΑΥΣΗΣ","Θλίψη","Καυστικές","Μέθοδος συνοριακών στοιχείων","Μηχανική θραύσεων","ΠΑΡΑΜΟΡΦΩΣΗ ΡΩΓΜΗΣ","Τριβή","Επιστήμες Μηχανικού και Τεχνολογία","Μηχανική Υλικών","Engineering and Technology","Materials Engineering"],"languages":["gre"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["10.12681/eadd/1192"],"render_values":[{"text":"10.12681/eadd/1192","href":"https://doi.org/10.12681/eadd/1192","code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10442/hedi/1192","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Σακελλαρίου, Μιχαήλ"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["1989"]},{"key":"dc:publisher","label":"Institution","values":["National Technical University of Athens (NTUA)","Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ)"]},{"key":"dc:type","label":"Dc Type","values":["PhD Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Brazilian test","Caustics","Compression","CRACK DEFORMATION","Crack propagation","FRACTURE INITIATION","Fracture mechanics","Friction","Shear","STICK-SLIP, BOUNDARY ELEMENT METHOD","ΒΡΑΖΙΛΙΑΝΗ ΔΟΚΙΜΗ","Διάδοση ρωγμής","Διάτμηση","ΕΝΑΡΞΗ ΘΡΑΥΣΗΣ","Θλίψη","Καυστικές","Μέθοδος συνοριακών στοιχείων","Μηχανική θραύσεων","ΠΑΡΑΜΟΡΦΩΣΗ ΡΩΓΜΗΣ","Τριβή","Επιστήμες Μηχανικού και Τεχνολογία","Μηχανική Υλικών","Engineering and Technology","Materials Engineering"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["gre"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["10.12681/eadd/1192","http://hdl.handle.net/10442/hedi/1192"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["THE CALCULATION OF THE STRESSES DEVELOPED ALONG THE CRACK FLANKS DUE TO COMPRESSION AND SHEARING IN THE FIRST TOPIC OF THIS THESIS . A CORRELATION MODEL HAS BEEN INTRODUCED IN ORDER TO CORRECT THE INCOMPATIBLE IN-PLANE DISPLACEMENTS, WHICH ARE PRODUCED BY THE SHEAR STRESSES. THE RESULT OF THIS CORRECTION IS, THE DEVELOPMENT OF AN ADDITIONAL COMPRESSION ALONG THE CRACK LIPS. THE EFFECT OF THESE STRESSES IS THE DEVELOPMENT OF A POSITIVE (TENSILE) KI-SIF AT THE CRACK TIPS.THIS SMALL, POSITIVE KI-SIF INSIDE AN OVERALL COMPRESSIVE STRESS FIELD IS CAUSING THE DEVIATION OF THE CRACK PROPAGATION UNDER COMPRESSION. IN THIS WAY THE PROPAGATED CRACK IN FOLLOWING A PATH TOWARDS THE COMPRESSIVE STRESS. THIS ASSUMPTION IS TESTED WITH EXPERIMENTS IN PLATES MADE BY PMMA, WITH SLITS AND CRACKS. IN ORDER TO EXAMINE THE TYPE OF THE STRESS FIELD AT THE TIPS OF THE PROPAGATED CRACKS, THE METHOD OF CAUSTICS HAS BEEN USED. THE METHOD WAS PREVIOUSLY TESTED IN A SERIES OF EXPERIMENTS ON MODELS WITH CRACKS AND SLITS UNDER COMPRESSION. THE EXPERIMENTAL RESULTS WERE IN AGREEMENT WITH THE ASSUMPTIONS MADE IN THE THEORETICAL PART OF THE DISSERTATION.","Ο ΥΠΟΛΟΓΙΣΜΟΣ ΤΩΝ ΤΑΣΕΩΝ ΟΙ ΟΠΟΙΕΣ ΑΝΑΠΤΥΣΣΟΝΤΑΙ ΣΤΑ ΣΥΝΟΡΑ ΡΩΓΜΗΣ ΛΟΓΩ ΘΛΙΨΕΩΣΚΑΙ ΔΙΑΤΜΙΣΕΩΣ ΑΠΟΤΕΛΕΙ ΤΟ ΠΡΩΤΟ ΑΝΤΙΚΕΙΜΕΝΟ ΤΗΣ ΔΙΑΤΡΙΒΗΣ. ΕΙΣΑΓΕΤΑΙ ΕΝΑ ΜΟΝΤΕΛΟ ΔΙΟΡΘΩΣΗΣ ΓΙΑ ΤΗΝ ΑΝΑΙΡΕΣΗ ΤΩΝ ΜΗ-ΣΥΜΒΙΒΑΣΤΩΝ ΣΥΝΕΠΙΠΕΔΩΝ ΠΑΡΑΜΟΡΦΩΣΕΩΝ ΟΙ ΟΠΟΙΕΣ ΟΦΕΙΛΟΝΤΑΙ ΣΤΙΣ ΔΙΑΤΜΗΤΙΚΕΣ ΤΑΣΕΙΣ. ΤΟ ΑΠΟΤΕΛΕΣΜΑ ΑΥΤΗΣ ΤΗΣ ΔΙΟΡΘΩΣΗΣ ΕΙΝΑΙ Η ΑΝΑΠΤΥΞΗ ΠΡΟΣΘΕΤΗΣ ΘΛΙΨΗΣ ΣΤΑ ΧΕΙΛΗ ΤΗΣ ΡΩΓΜΗΣ. ΑΠΟΤΕΛΕΣΜΑ ΑΥΤΩΝ ΤΩΝ ΤΑΣΕΩΝ ΕΙΝΑΙ Η ΑΝΑΠΤΥΞΗ ΘΕΤΙΚΟΥ (ΕΦΕΛΚΥΣΜΟΥ) ΚΙ-SIF ΣΤΑ ΑΚΡΑ ΤΗΣ ΡΩΓΜΗΣ. Η ΠΑΡΟΥΣΙΑΘΕΤΙΚΟΥ ΚΙ ΕΝΤΟΣ ΘΛΙΠΤΙΚΟΥ ΤΑΣΙΚΟΥ ΠΕΔΙΟΥ ΠΡΟΚΑΛΕΙ ΤΗΝ ΑΠΟΚΛΙΣΗ ΤΗΣ ΡΩΓΜΗΣ ΚΑΤΑ ΤΗΝ ΔΙΑΔΟΣΗ ΚΑΙ ΘΛΙΠΤΙΚΗ ΤΑΣΗ. ΓΙΑ ΤΟΝ ΕΛΕΓΧΟ ΑΥΤΗΣ ΤΗΣ ΠΑΡΑΔΟΧΗΣ ΕΓΙΝΑΝ ΔΟΚΙΜΕΣ ΣΕ ΠΛΑΚΕΣ, ΜΕ ΕΓΚΟΠΕΣ ΚΑΙ ΡΩΓΜΕΣ, ΑΠΟ PMMA. ΓΙΑ ΤΗΝ ΕΞΕΤΑΣΗ ΤΟΥ ΤΥΠΟΥ ΤΟΥ ΤΑΣΙΚΟΥ ΠΕΔΙΟΥ ΣΤΑ ΑΚΡΑ ΤΗΣ ΔΙΑΔΙΔΟΜΕΝΗΣ ΡΩΓΜΗΣ, ΧΡΗΣΙΜΟΠΟΙΗΘΗΚΕ Η ΜΕΘΟΔΟΣ ΤΩΝ ΚΑΥΣΤΙΚΩΝ. ΠΡΟΗΓΟΥΜΕΝΩΣ ΕΓΙΝΕ ΕΛΕΓΧΟΣ ΤΟΥ ΤΑΣΙΚΟΥ ΠΕΔΙΟΥ ΣΤΑ ΑΚΡΑ ΣΤΑΣΙΜΩΝ ΕΓΚΟΠΩΝ ΚΑΙ ΡΩΓΜΩΝ ΥΠΟ ΘΛΙΨΗ ΚΑΙ ΔΙΑΤΜΙΣΗ. ΤΑ ΠΕΙΡΑΜΑΤΙΚΑ ΑΠΟΤΕΛΕΣΜΑΤΑ, ΗΣΑΝ ΣΕ ΣΥΜΦΩΝΙΑ ΜΕ ΤΙΣ ΠΑΡΑΔΟΧΕΣ ΠΟΥ ΕΓΙΝΑΝ ΣΤΟ ΘΕΩΡΗΤΙΚΟ ΜΕΡΟΣ ΤΗΣ ΔΙΑΤΡΙΒΗΣ."]},{"key":"dc:title","label":"Title","values":["ΕΠΙΔΡΑΣΗ ΤΗΣ ΠΑΡΟΥΣΙΑΣ ΡΩΓΜΩΝ ΣΤΗΝ ΚΑΤΑΝΟΜΗ ΤΗΣ ΕΝΤΑΣΕΩΣ ΣΕ ΘΛΙΒΟΜΕΝΑ ΣΩΜΑΤΑ. ΕΦΑΡΜΟΓΕΣ ΣΤΗΝ ΠΕΡΙΟΧΗ ΤΗΣ ΒΡΑΧΟΜΗΧΑΝΙΚΗΣ","INFLUENCE OF THE PRESENCE OF CRACKS IN THE STRESS FIELD OF COMPRESSED BODIES. APPLICATIONS IN ROCK MECHANICS"]}]}],"canonical_facts":{"dc:creator":["Σακελλαρίου, Μιχαήλ"],"dc:date":["1989"],"dc:description":["THE CALCULATION OF THE STRESSES DEVELOPED ALONG THE CRACK FLANKS DUE TO COMPRESSION AND SHEARING IN THE FIRST TOPIC OF THIS THESIS . A CORRELATION MODEL HAS BEEN INTRODUCED IN ORDER TO CORRECT THE INCOMPATIBLE IN-PLANE DISPLACEMENTS, WHICH ARE PRODUCED BY THE SHEAR STRESSES. THE RESULT OF THIS CORRECTION IS, THE DEVELOPMENT OF AN ADDITIONAL COMPRESSION ALONG THE CRACK LIPS. THE EFFECT OF THESE STRESSES IS THE DEVELOPMENT OF A POSITIVE (TENSILE) KI-SIF AT THE CRACK TIPS.THIS SMALL, POSITIVE KI-SIF INSIDE AN OVERALL COMPRESSIVE STRESS FIELD IS CAUSING THE DEVIATION OF THE CRACK PROPAGATION UNDER COMPRESSION. IN THIS WAY THE PROPAGATED CRACK IN FOLLOWING A PATH TOWARDS THE COMPRESSIVE STRESS. THIS ASSUMPTION IS TESTED WITH EXPERIMENTS IN PLATES MADE BY PMMA, WITH SLITS AND CRACKS. IN ORDER TO EXAMINE THE TYPE OF THE STRESS FIELD AT THE TIPS OF THE PROPAGATED CRACKS, THE METHOD OF CAUSTICS HAS BEEN USED. THE METHOD WAS PREVIOUSLY TESTED IN A SERIES OF EXPERIMENTS ON MODELS WITH CRACKS AND SLITS UNDER COMPRESSION. THE EXPERIMENTAL RESULTS WERE IN AGREEMENT WITH THE ASSUMPTIONS MADE IN THE THEORETICAL PART OF THE DISSERTATION.","Ο ΥΠΟΛΟΓΙΣΜΟΣ ΤΩΝ ΤΑΣΕΩΝ ΟΙ ΟΠΟΙΕΣ ΑΝΑΠΤΥΣΣΟΝΤΑΙ ΣΤΑ ΣΥΝΟΡΑ ΡΩΓΜΗΣ ΛΟΓΩ ΘΛΙΨΕΩΣΚΑΙ ΔΙΑΤΜΙΣΕΩΣ ΑΠΟΤΕΛΕΙ ΤΟ ΠΡΩΤΟ ΑΝΤΙΚΕΙΜΕΝΟ ΤΗΣ ΔΙΑΤΡΙΒΗΣ. ΕΙΣΑΓΕΤΑΙ ΕΝΑ ΜΟΝΤΕΛΟ ΔΙΟΡΘΩΣΗΣ ΓΙΑ ΤΗΝ ΑΝΑΙΡΕΣΗ ΤΩΝ ΜΗ-ΣΥΜΒΙΒΑΣΤΩΝ ΣΥΝΕΠΙΠΕΔΩΝ ΠΑΡΑΜΟΡΦΩΣΕΩΝ ΟΙ ΟΠΟΙΕΣ ΟΦΕΙΛΟΝΤΑΙ ΣΤΙΣ ΔΙΑΤΜΗΤΙΚΕΣ ΤΑΣΕΙΣ. ΤΟ ΑΠΟΤΕΛΕΣΜΑ ΑΥΤΗΣ ΤΗΣ ΔΙΟΡΘΩΣΗΣ ΕΙΝΑΙ Η ΑΝΑΠΤΥΞΗ ΠΡΟΣΘΕΤΗΣ ΘΛΙΨΗΣ ΣΤΑ ΧΕΙΛΗ ΤΗΣ ΡΩΓΜΗΣ. ΑΠΟΤΕΛΕΣΜΑ ΑΥΤΩΝ ΤΩΝ ΤΑΣΕΩΝ ΕΙΝΑΙ Η ΑΝΑΠΤΥΞΗ ΘΕΤΙΚΟΥ (ΕΦΕΛΚΥΣΜΟΥ) ΚΙ-SIF ΣΤΑ ΑΚΡΑ ΤΗΣ ΡΩΓΜΗΣ. Η ΠΑΡΟΥΣΙΑΘΕΤΙΚΟΥ ΚΙ ΕΝΤΟΣ ΘΛΙΠΤΙΚΟΥ ΤΑΣΙΚΟΥ ΠΕΔΙΟΥ ΠΡΟΚΑΛΕΙ ΤΗΝ ΑΠΟΚΛΙΣΗ ΤΗΣ ΡΩΓΜΗΣ ΚΑΤΑ ΤΗΝ ΔΙΑΔΟΣΗ ΚΑΙ ΘΛΙΠΤΙΚΗ ΤΑΣΗ. ΓΙΑ ΤΟΝ ΕΛΕΓΧΟ ΑΥΤΗΣ ΤΗΣ ΠΑΡΑΔΟΧΗΣ ΕΓΙΝΑΝ ΔΟΚΙΜΕΣ ΣΕ ΠΛΑΚΕΣ, ΜΕ ΕΓΚΟΠΕΣ ΚΑΙ ΡΩΓΜΕΣ, ΑΠΟ PMMA. ΓΙΑ ΤΗΝ ΕΞΕΤΑΣΗ ΤΟΥ ΤΥΠΟΥ ΤΟΥ ΤΑΣΙΚΟΥ ΠΕΔΙΟΥ ΣΤΑ ΑΚΡΑ ΤΗΣ ΔΙΑΔΙΔΟΜΕΝΗΣ ΡΩΓΜΗΣ, ΧΡΗΣΙΜΟΠΟΙΗΘΗΚΕ Η ΜΕΘΟΔΟΣ ΤΩΝ ΚΑΥΣΤΙΚΩΝ. ΠΡΟΗΓΟΥΜΕΝΩΣ ΕΓΙΝΕ ΕΛΕΓΧΟΣ ΤΟΥ ΤΑΣΙΚΟΥ ΠΕΔΙΟΥ ΣΤΑ ΑΚΡΑ ΣΤΑΣΙΜΩΝ ΕΓΚΟΠΩΝ ΚΑΙ ΡΩΓΜΩΝ ΥΠΟ ΘΛΙΨΗ ΚΑΙ ΔΙΑΤΜΙΣΗ. ΤΑ ΠΕΙΡΑΜΑΤΙΚΑ ΑΠΟΤΕΛΕΣΜΑΤΑ, ΗΣΑΝ ΣΕ ΣΥΜΦΩΝΙΑ ΜΕ ΤΙΣ ΠΑΡΑΔΟΧΕΣ ΠΟΥ ΕΓΙΝΑΝ ΣΤΟ ΘΕΩΡΗΤΙΚΟ ΜΕΡΟΣ ΤΗΣ ΔΙΑΤΡΙΒΗΣ."],"dc:identifier":["10.12681/eadd/1192","http://hdl.handle.net/10442/hedi/1192"],"dc:language":["gre"],"dc:publisher":["National Technical University of Athens (NTUA)","Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ)"],"dc:subject":["Brazilian test","Caustics","Compression","CRACK DEFORMATION","Crack propagation","FRACTURE INITIATION","Fracture mechanics","Friction","Shear","STICK-SLIP, BOUNDARY ELEMENT METHOD","ΒΡΑΖΙΛΙΑΝΗ ΔΟΚΙΜΗ","Διάδοση ρωγμής","Διάτμηση","ΕΝΑΡΞΗ ΘΡΑΥΣΗΣ","Θλίψη","Καυστικές","Μέθοδος συνοριακών στοιχείων","Μηχανική θραύσεων","ΠΑΡΑΜΟΡΦΩΣΗ ΡΩΓΜΗΣ","Τριβή","Επιστήμες Μηχανικού και Τεχνολογία","Μηχανική Υλικών","Engineering and Technology","Materials Engineering"],"dc:title":["ΕΠΙΔΡΑΣΗ ΤΗΣ ΠΑΡΟΥΣΙΑΣ ΡΩΓΜΩΝ ΣΤΗΝ ΚΑΤΑΝΟΜΗ ΤΗΣ ΕΝΤΑΣΕΩΣ ΣΕ ΘΛΙΒΟΜΕΝΑ ΣΩΜΑΤΑ. ΕΦΑΡΜΟΓΕΣ ΣΤΗΝ ΠΕΡΙΟΧΗ ΤΗΣ ΒΡΑΧΟΜΗΧΑΝΙΚΗΣ","INFLUENCE OF THE PRESENCE OF CRACKS IN THE STRESS FIELD OF COMPRESSED BODIES. APPLICATIONS IN ROCK MECHANICS"],"dc:type":["PhD Thesis"]},"updated_at":"2026-07-24T02:24:46Z"}