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Σχεδιασμóς αστικών δικτύων αποχέτευσης (Design of Urban Sewer Networks)

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Το βιβλίο καλύπτει θέματα σχεδιασμού και λειτουργικού ελέγχου των δικτύων αποχέτευσης. Περιλαμβάνει στοιχεία από την ελληνική τεχνολογική εμπειρία στα αποχετευτικά έργα (μεθοδολογίες και προδιαγραφές) με παράλληλη αναφορά σε στοιχεία της διεθνούς βιβλιογραφίας. Δίνει έμφαση στις επιστημονικές αρχές που αιτιολογούν τις προδιαγραφές και τις μεθοδολογίες. Επίσης, ενσωματώνει και ορισμένα πρωτότυπα στοιχεία. Αποτελείται από οκτώ κεφάλαια. Στο πρώτο δίνονται οι βασικές έννοιες και οι ορισμοί μαζί με ένα σύντομο ιστορικό και μια γενική περιγραφή των μελετών αποχέτευσης. Στο δεύτερο κεφάλαιο αναφέρονται οι μέθοδοι εκτίμησης των παροχών ακαθάρτων, με παράθεση χρήσιμων δεδομένων, ελληνικών και διεθνών. Στο τρίτο κεφάλαιο δίνεται η τυπική μεθοδολογία εκτίμησης των παροχών ομβρίων, με ιδιαίτερη αναφορά στις ελληνικές συνθήκες (παράθεση τυπικών όμβριων καμπυλών, κτλ.). Το τέταρτο κεφάλαιο καλύπτει τους υδραυλικούς υπολογισμούς που είναι απαραίτητοι για το σχεδιασμό, τον έλεγχο επάρκειας και την εκτίμηση των χαρακτηριστικών ροής των αγωγών αποχέτευσης. Έμφαση δίνεται στην αντιμετώπιση ορισμένων μη τυπικών καταστάσεων λειτουργίας των αγωγών (πχ. πολύ μεγάλες ή πολύ μικρές κλίσεις και ταχύτητες), οι οποίες μπορεί να προκαλέσουν σοβαρά προβλήματα στη λειτουργία των δικτύων. Στο πέμπτο κεφάλαιο παρουσιάζονται οι πιο σύγχρονες αντιλήψεις και υπολογιστικές μέθοδοι των αποχετευτικών δικτύων που βασίζονται στην συνολική προσομοίωση της λειτουργίας τους (υδρολογική και υδραυλική). Το έκτο κεφάλαιο καλύπτει ορισμένα ποιοτικά θέματα τα οποία συναρτώνται με το σχεδιασμό και τον έλεγχο της λειτουργίας των δικτύων, όπως είναι η παραγωγή και απελευθέρωση υδροθείου στους αγωγούς και οι συνέπειές της. Στο έβδομο κεφάλαιο περιλαμβάνονται τεχνολογικά θέματα, όπως η επιλογή υλικών για τους προκατασκευασμένους σωλήνες, ο τρόπος κατασκευής των χυτών επί τόπου αγωγών και η αντιδιαβρωτική προστασία των αγωγών λυμάτων. Τέλος, στο όγδοο κεφάλαιο δίνονται πληροφορίες για κάποια εναλλακτικά συστήματα αποχέτευσης. Μερικές από τις πρωτότυπες αναλύσεις που περιλαμβάνονται στο βιβλίο είναι: (α) η στατιστική θεμελίωση και μοντελοποίηση της διακύμανσης των παροχών ακαθάρτων, (β) η κατάρτιση αλγορίθμων αριθμητικής επίλυσης διάφορων υδραυλικών προβλημάτων, (γ) η εξαγωγή αναλυτικών σχέσεων που μπορούν να αντικαταστήσουν διάφορα εμπειρικά νομογραφήματα ή πίνακες της βιβλιογραφίας (π.χ. εξίσωση μεταβολής της τραχύτητας συναρτήσει του αδιαστατοποιημένου βάθους ροής σε κυκλικούς αγωγούς, αντίστοιχη εξίσωση για τον άμεσο προσεγγιστικό υπολογισμό του κρίσιμου βάθους σε κυκλικούς αγωγούς, εξίσωση εκτίμησης του συντελεστή τοπικών απωλειών σε συμβολές αποχετευτικών αγωγών), και (δ) η συστηματοποίηση και μεταφορά στο σύστημα μονάδων SI διάφορων εμπειρικών εξισώσεων της βιβλιογραφίας (π.χ. εξισώσεις εκτίμησης χρόνων συρροής ομβρίων, εξισώσεις παραγωγής υδροθείου, κ.ά.).
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... Spatial interpolation of rainfall intensity data is conducted using Spline technique and the areal reduction factor are implemented in order to obtain the final rainfall pattern of the study area. In Figure 4, we present the precipitation map derived from the observations of the in situ meteorological stations of 50 years return period for the study area, as a result of our analysis [51,52]. ...
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