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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Quantitative Design Decision Method: Performance-Based Design Utilizing A Risk Analysis Framework

Hurd, Melinda E. January 2012 (has links)
The model building and fire codes in Canada permit prescriptive-based design and performance-based design approaches. Within this regulatory framework, prescriptive-based designs are attributed objective and functional statements to qualify the level of fire protection and life safety required. Performance-based designs, or alternative solutions to prescriptive-based designs, must be demonstrated to achieve at least an equivalent level of performance as the prescriptive requirement based on evaluation of each associated objective and functional statement. Due to the qualitative performance descriptions available, the current system for developing and reviewing alternative solutions is vulnerable to the acceptance of over-designed or under-designed life safety and fire protection measures in buildings. The objective of this thesis is to establish a method to compare the performance of alternative solutions with prescriptive design requirements on a quantitative basis. This thesis generates eight objectives for a fire risk analysis tool to address the challenges identified in the building regulatory industry. Based on review of existing techniques, a new fire risk analysis framework is developed. The Quantitative Design Decision (QDD) method, integrates risk analysis with quantitative decision assessment techniques to facilitate application-specific quantification of performance objectives and to aid evaluation of performance-based designs. The method utilizes an iterative three-stage structure. To demonstrate the application of the QDD method, a case-study simulation has been conducted. The case-study provides an evaluation of alternative designs to the prescriptive requirements for explosion-relief ventilation in rooms housing flammable vapour producing operations. The case study supports the conclusion that QDD achieves the eight objectives set out in this thesis. For validation, the QDD method must be applied to a wider variety of practical design challenges and it is recommended that the results be considered in conjunction with live fire test data to verify key aspects of the performance decisions generated. Future work should include evaluation of Delphi technique application in the Design Decision Stage of the QDD method. It is proposed that the method developed can be extended for use as a general performance-based design tool.
42

Risk attitudes and safety culture in the English fire and rescue services

Wood, Geoffrey Tempest January 2017 (has links)
In the ten year period between 2004 and 2013 the UK lost 13 operational, and one non-operational, firefighters at fires, a relatively large number in relation to previous losses. These fatalities occurred during a period in which fire fatalities of members of the public were at an all‐time low but fire and rescue services (FRS) and their staff were being accused in the media of becoming risk averse. This research was focussed on investigating the risk attitudes and safety culture in the English fire and rescue services. The research question asked how the safety culture manifests itself in the English fire and rescue service and what are its implications? A mixed approach to the research was adopted utilising both quantitative and qualitative methods. The research strategy was inductive using a multiple case study. A safety culture questionnaire was designed and then piloted in one FRS with the responses being subjected to a factor analysis the results of which indicated there were four dimensions: management, procedures, competence, and work pressures. The final version of the questionnaire was then distributed across five FRSs from which 845 were returned, of which 823 were used in a series of statistical analyses. Two independent variables were used in the analysis; the first consisted of the individual FRSs, the second consisted of three groups based on Schein’s three generic subcultures of executive, designer and operator. These were aligned with principal officers (PO), senior officers (SO), and Watch based (WB) staff respectively. The analysis of the completed questionnaires indicated that the WB group had a negative attitude towards their FRS safety culture, while the SO and PO groups had a more positive attitude with the PO the most positive. All three groups were significantly different to each other. In conducting the qualitative part of the mixed methods the researcher rode with three Watches at a station in each of three FRSs to observe the behaviour of WB staff and attending SOs at incidents and during their daily activities. During the course of the fieldwork nineteen members across all of the participating FRSs were interviewed, and twenty‐four focus groups were conducted. What was clear was that the competence based training system was not popular with WB staff who believed it to be too bureaucratic, whilst SOs and POs believed that it had not fulfilled their expectations of what it would deliver. There were also concerns expressed that the promotion system, associated with the competence‐based training, was producing managers and not the leaders required on the incident ground. It was concluded that safety culture within the FRS is associated with the systems, policies and procedures reflective of FRS management’s level of risk tolerance producing a rule-based decision‐making bureaucracy; this level of risk tolerance then influences how operational firefighters operate on the incident ground. In the world of the operational firefighter a typical incident, which by its very nature is a temporary event, is laden with uncertainty, complexity and in which all the potential risks may not yet have been identified with decision‐making being focussed on problem‐solving. FRS personnel find themselves operating in a risk climate in which they build temporary command structures, construct temporary processes and controls reflecting the incident commander’s risk appetite for the purpose of moving towards operating in a safety climate in which to resolve the incident. The combination of the FRS’s safety culture and the operational firefighter’s risk climate determine what the researcher has defined as the FRS operational culture.
43

Suomalainen puukerrostalo puurakentamisen kehittämisen etulinjassa

Karjalainen, M. (Markku) 18 March 2002 (has links)
Abstract The objective of this study is to examine and shed light on the process of developing Finnish multi-story timber apartment buildings. It deals with the basic problems and technical solutions related to multi-story timber apartment buildings. The study also examines the background, principles, objectives and fundamentals of Finnish multi-story timber apartment building construction and describes the main questions, activities and events related to the development of Finnish timber construction, especially from the 1990s to the beginning of the new millennium. This study provides a general idea of the present situation and future challenges in the development of the Finnish multi-story timber apartment building. The results of the study that are given the most emphasis are multi-story timber apartment building fire safety, the space cost factor and feedback from residents. The study also presents Finland's first multi-story timber apartment building sites and their technical designs. Ten multi-story timber apartment buildings containing 338 apartments were constructed in Finland in 1995–2001. The next two sites will be completed in 2002. The national publicity and feedback of the multi-story timber apartment buildings has primarily been positive. Multi-story timber apart-ment buildings have not, however, made an actual break-through in Finland. Multi-story timber apartment building construction has been hindered by many biases and the impression that the con-struction is experimental and expensive. Many of these doubts and biases have been exaggerated. The period of experimental construction of multi-story timber apartment buildings in Finland has indicated that technical issues, such as construction techniques, issues related to heating, sound, fire, water and moisture insulation, and HVAC installation, are manageable. A survey of residents indicates that they have a positive attitude toward multi-story timber apartment buildings, and residents hope wood will be used more in Finland. Multi-story timber apartment buildings are felt to be cosy and pleasant, they have a good indoor climate, they are functional, architecturally successful, fire-safe and well insulated against airborne sounds. On the basis of the survey of residents, special attention should be given to impact sound insulation in the intermediate floors. The residents would like to see more wood used in the stairways and interior facing. Space cost is an important factor from the standpoint of the competitiveness of multi-story timber apartment building construction. According to the currently used definition of permitted building volume based on gross floor area, the space cost of a multi-story timber apartment building constructed using current frame designs, which utilise load-bearing inner walls and short spans, is less advantageous than that of concrete frame buildings, which utilise long slab intermediate floors. Construction methods that utilise different construction materials and frame designs would be more on par if the concept of permitted building volume were based on net floor area. The fire code of multi-story timber apartment buildings still requires revising. For example, the Finnish fire code recommends visible protruding fire stops on high wooden façades. Nevertheless, these fire stops do not function as intended, and in some cases they even contribute to the spreading of a façade fire. Instead of using visible protruding fire stops, the spreading of a small façade fire can be effectively limited by partitioning the air space behind the facing in the horizontal direction and by using horizontal structures in the air space that choke the spreading of a fire in the air space. Based on housing statistics, there is a potential market in Finland for multi-story timber apartment buildings: 43,7 % of Finns live in a multi-story apartment building, and 75 % of all multi-story apartment buildings have less than five stories, which according to current regulations means they could be constructed out of wood. In order to make multi-story timber apartment buildings competitive, their construction should be continuous, experience in their construction should be accumulated and their technical designs should become established procedure. The ecology and market value of the life cycle of timber construction should be exploited more than is presently done. Developers and residents have a central role in making multi-story timber apartment buildings more common. / Tiivistelmä Tutkimuksen tavoitteena on selvittää ja valottaa suomalaisen puukerrostalon kehittämisprosessia käymällä läpi ongelmakeskeisesti puukerrostalojen peruskysymyksiä ja teknisiä ratkaisuja. Tutkimuksessa tarkastellaan maamme puukerrostalorakentamisen taustoja, lähtökohtia, tavoitteita ja perusteita sekä kuvataan niitä keskeisiä kysymyksiä, toimenpiteitä ja tapahtumia, mitä suomalaisen puurakentamisen kehitystyössä on tehty ja kohdattu erityisesti 1990-luvulta uuden vuosituhannen alkuun. Tutkimuksen perusteella muodostetaan yleiskäsitys suomalaisen puukerrostalon kehitystyön nykytilanteesta ja tulevaisuuden haasteista. Tutkimustuloksista keskeiselle sijalle on asetettu puukerrostalojen paloturvallisuus, tilakustannustekijä ja asukaspalaute. Tutkimuksessa esitellään myös maamme ensimmäiset puukerrostalokohteet teknisine ratkaisuineen. Vuosina 1995–2001 Suomeen on rakennettu kymmenen puukerrostalokohdetta, yhteensä 338 asuntoa. Kaksi seuraavaa kohdetta valmistuvat vuonna 2002. Puukerrostalojen valtakunnallinen julkisuus ja palaute on ollut pääasiassa myönteistä. Puukerrostalot eivät ole kuitenkaan tehneet varsinaista läpimurtoa Suomessa. Puukerrostalorakentamista ovat rasittaneet useat ennakkoasenteet sekä koerakentamisen ja kalliin rakentamisen leima. Monet näistä epäilyistä ja ennakkoluuloista ovat olleet liioiteltuja. Suomalaisten puukerrostalojen koerakentamisaika on osoittanut, että puukerrostalojen tekniset kysymykset, kuten rakentamistekniikka, lämmön-, äänen-, palon-, veden- ja kosteudeneristyskysymykset sekä LVIS-asennustekniikkaan liittyvät asiat pystytään hallitsemaan. Asukaskyselytutkimuksessa asukkaat suhtautuivat puukerrostaloihin myönteisesti, ja puurakentamista ja puun käyttöä toivottiin lisättävän maassamme. Puukerrostaloja pidettiin yleisesti kodikkaina, viihtyisinä, sisäilmastoltaan hyvinä, toimivina, arkkitehtuuriltaan onnistuneina, paloturvallisina ja ilmaääneneristykseltään hyvinä. Asukaskyselyn perusteella puukerrostalojen keveiden välipohjien askelääneneristävyyteen on kiinnitettävä erityistä huomiota. Asukkaat toivoivat puuta käytettävän tähänastista enemmän porrashuoneiden ja asuntojen sisäpintaverhouksissa. Tilakustannus on keskeinen tekijä puukerrostalorakentamisen kilpailukyvyn kannalta. Tähänastisilla teknisillä ratkaisuilla ja kantaviin väliseiniin ja lyhyihin jänneväleihin perustuvalla runkojärjestelmällä rakennettu puukerrostalo on tilakustannuksiltaan tavanomaista pitkälaattavälipohjaista betonirunkokerrostaloa epäedullisempi nykyisen kerrosalaan perustuvan rakennusoikeuden määritelmän mukaan. Eri rakennusmateriaaleilla ja runkojärjestelmillä toteutettavat rakentamistavat tulisivat nykyistä tasa-arvoisemmiksi, jos rakennusoikeuden käsite muutettaisiin nettoalaan perustuvaksi. Puukerrostalojen palosäädökset kaipaavat tarkentamista. Esimerkiksi Suomen palosäädöksissä suositeltavat korkeiden puujulkisivujen näkyvät palokatkoulokkeet eivät käytännössä toimi toivotulla tavalla, ja joissakin tapauksissa ne jopa edistävät julkisivupalon leviämistä. Näkyvien palokatkoulokkeiden sijasta pienehkön julkisivupalon leviämistä voidaan rajoittaa tehokkaasti kaistoittamalla julkisivun taustan tuuletusrakoa sivuttaissuunnassa ja käyttämällä tuuletusraossa vaakasuuntaisia rakenteita, joilla tukahdutetaan palon leviäminen tuuletusraossa. Asumistilastojen valossa suomalaisille puukerrostaloille voisi olla potentiaaliset markkinat: 43,7 % suomalaisista asuu kerrostalossa, ja 75 % kaikista kerrostaloista on alle 5-kerroksisia, eli ne voitaisiin nykymääräysten mukaan toteuttaa puisina. Jotta puukerrostalojen kilpailukyky paranisi, tarvitaan niiden rakentamisessa jatkuvuutta ja harjaantumista sekä teknisten ratkaisujen vakiinnuttamista. Puurakentamisen ekologisuutta ja elinkaarimarkkina-arvoa tulisi hyödyntää tähänastista enemmän. Rakennuttajat ja asukkaat ovat keskeisessä roolissa puukerrostalojen yleistymisessä.
44

Dual-Attention Generative Adversarial Network and Flame and Smoke Analysis

Li, Yuchuan 30 September 2021 (has links)
Flame and smoke image processing and analysis could improve performance to detect smoke or fire and identify many complicated fire hazards, eventually to help firefighters to fight fires safely. Deep Learning applied to image processing has been prevailing in recent years among image-related research fields. Fire safety researchers also brought it into their studies due to its leading performance in image-related tasks and statistical analysis. From the perspective of input data type, traditional fire research is based on simple mathematical regressions or empirical correlations relying on sensor data, such as temperature. However, data from advanced vision devices or sensors can be analyzed by applying deep learning beyond auxiliary methods in data processing and analysis. Deep Learning has a bigger capacity in non-linear problems, especially in high-dimensional spaces, such as flame and smoke image processing. We propose a video-based real-time smoke and flame analysis system with deep learning networks and fire safety knowledge. It takes videos of fire as input and produces analysis and prediction for flashover of fire. Our system consists of four modules. The Color2IR Conversion module is made by deep neural networks to convert RGB video frames into InfraRed (IR) frames, which could provide important thermal information of fire. Thermal information is critically important for fire hazard detection. For example, 600 °C marks the start of a flashover. As RGB cameras cannot capture thermal information, we propose an image conversion module from RGB to IR images. The core of this conversion is a new network that we innovatively proposed: Dual-Attention Generative Adversarial Network (DAGAN), and it is trained using a pair of RGB and IR images. Next, Video Semantic Segmentation Module helps extract flame and smoke areas from the scene in the RGB video frames. We innovated to use synthetic RGB video data generated and captured from 3D modeling software for data augmentation. After that, a Video Prediction Module takes the RGB video frames and IR frames as input and produces predictions of the subsequent frames of their scenes. Finally, a Fire Knowledge Analysis Module predicts if flashover is coming or not, based on fire knowledge criteria such as thermal information extracted from IR images, temperature increase rate, the flashover occurrence temperature, and increase rate of lowest temperature. For our contributions and innovations, we introduce a novel network, DAGAN, by applying foreground and background attention mechanisms in the image conversion module to help reduce the hardware device requirement for flashover prediction. Besides, we also make use of combination of thermal information from IR images and segmentation information from RGB images in our system for flame and smoke analysis. We also apply a hybrid design of deep neural networks and a knowledge-based system to achieve high accuracy. Moreover, data augmentation is also applied on the Video Semantic Segmentation Module by introducing synthetic video data for training. The test results of flashover prediction show that our system has leading places quantitative and qualitative in terms of various metrics compared with other existing approaches. It can give a flashover prediction as early as 51 seconds with 94.5% accuracy before it happens.
45

Zhodnocení úrovně vybavenosti vybraných památkových objektů v České a Slovenské republice z hlediska jejich protipožárního zabezpečení / Assessment of the level of equipment of selected historical buildings in the Czech republic and in Slovakia in terms of fire safety

SVOBODA, Petr January 2016 (has links)
This thesis deals with the issue of fire protection of historical buildings in the Czech and Slovak Republics. Input information that was used in the thesis were obtained from the literature or other freely accessible sources, the Fire Brigade of the Czech Republic, the Fire and Rescue Service of the Slovak Republic and the owners or managers of buildings. The main objective is to evaluate the facilities of selected historical buildings in terms of fire protection. According the objective has been defined the research question "Are the monuments in the territory of the Czech and Slovak Republic secured in a comparable level against the risk of fire?". An integral part is also proposing possible technical and technological elements and organizational measures which may lead to increased fire safety of monuments on the territory of the two abovementioned republics. Fulfillment of goals was possible, based on our investigation, when the first identification of monuments in the Czech and Slovak Republics, whose owners, respectively. Administrators were asked to complete a questionnaire containing questions related to fourteen facilities surveyed the building fire safety equipment and material means of fire protection. The completion of that survey were also asked at the same time members of the Fire and Rescue Service geographically relevant regions of the Czech Republic and members of the Fire and Rescue Corps of the Slovak Republic. Specifically, there were members who are employed in divisions or departments of fire prevention of the competent authorities of the state fire supervision. After evaluating the data collected through questionnaires and in some cases based on electronic correspondence or telephone conversations has been possible to answer the research question. Based on available information it is apparently that the fire protection of historical buildings in the Czech and Slovak Republic are treated by the authorities, not only the state fire supervision, but also themselves owners or facility managers very seriously and the fire safety of these monuments can be described as comparable. Unfortunately, in the research failed to varify the availability of surveyed historical buildings for vehicles of emergency fire-fighting units, which was based on the results of the analysis identified as one of the most risky points of fire protection of monuments. It can therefore only consider whether the availability of objects of that type in terms driveways is satisfactory. Proposing of possible measures is done on the basis of not only the information collected from facility managers and bodies of the state fire supervision of both republics, but also on the basis of the KARS analysis, which aimed to identify the most threatening phenomena which could have a negative impact on the status quo of monuments, in terms of fire protection. Answering a defining research questions and performing the analysis using method KARS has been achieved the objective of this thesis. In addition to the methodology and outcomes of the research are in the thesis presented brief information concerning fire protection in the age of the buildings and structures construction, which are currently presents as heritage buildings, and basic information of the principles of fire protection of historical monuments under applicable laws of the Czech and Slovak Republic. Fire protection of historical buildings has been underestimated for years. Currently, in connection with the ensuing fires significant buildings of historical value, it is to safeguard of historical buildings against the emergence and spread of a fire and how to dispose of potential fire utmost importance. As in other areas or sectors, as well as in fire protection of historic buildings is particularly important in the prevention, thus adopting such a system of measures to prevent a fire, or if there is a fire that damages caused by extraordinary events are possible smallest.
46

Zhodnocení vlivu požárně bezpečnostních zařízení na bezpečnost unikajících osob z objektu / Evaluation of the impact of fire safety equipment for the safety of persons escaping from the building

MÍCHAL, Petr January 2012 (has links)
The safety evacuation from the fire affected building is the most imported thing, which is bound to the fire safety of building. The evacuation of persons is necessary process and procedure which can safe lives and health in the most of extraordinary event caused by fire of buildings or technologies. The typical efect attend fires set in buildings, which threaten persons, property and fire - fighting fire brigades. These threaten efects are products of combustion, flame, heat and deficiency of oxygen. I present the way how to use the fire safety devices in various types of buildings in my diploma work, above all towards to safety escape persons from the fire affected building. I describe the practical positive and also negative finding during installation and mutual coordination the fire safety devices.
47

Σχεδίαση-αποτύπωση με την βοήθεια του ηλεκτρονικού υπολογιστή (AUTOCAD) εγκαταστάσεων πυρασφάλειας και πυρόσβεσης των κτηρίων του τμήματος των Χημικών Μηχανικών

Αντωνάδος, Βασίλειος 13 October 2013 (has links)
Η προστασία της ανθρώπινης ζωής είναι βασική υποχρέωση της Πολιτείας και θεμελιακό δικαίωμα του πολίτη. Αυτονόητη είναι λοιπόν η προστασία ενός κτιρίου από τη φωτιά, ιδιαίτερα δε όταν πρόκειται για ένα εκπαιδευτήριο που φιλοξενεί εκατοντάδες ανθρώπους. Η παρούσα διπλωματική εργασία έχει ως αντικείμενο την αποτύπωση και την σχεδίαση των εγκαταστάσεων Πυρασφάλειας και Πυρόσβεσης του κτιρίου των Χημικών Μηχανικών. Μέσα από την διαδικασία της αποτύπωσης στόχος της διπλωματικής εργασίας είναι να διαπιστώσει αν οι μηχανισμοί πρόληψης, αντίδρασης αλλά και καταπολέμησης της φωτιάς του κτιρίου, επαρκούν ώστε να εκπληρώνονται οι βασικοί στόχοι της πυροπροστασίας. Δηλαδή, η ασφάλεια της ανθρώπινης ζωής και υγείας, η παρεμπόδιση εξάπλωσης της φωτιάς σε γειτονικά κτήρια ή σε άλλα διαμερίσματα του ίδιου κτιρίου, η ασφαλής εκκένωσή του και τέλος η προστασία της περιουσίας. Στο πρώτο κεφάλαιο δίνονται ορισμοί και βασικές έννοιες, παρουσιάζεται το τρίγωνο και το τετράεδρο της φωτιάς οι αιτίες πρόκλησης πυρκαγιών αλλά και η διάκριση των αιτιών ανάλογα με την πρόθεση ή την υπαιτιότητα. Γίνεται αναφορά στα είδη και τις κατηγορίες των πυρκαγιών. Περιγράφονται οι αρχές κατάσβεσης της φωτιάς που αποτελούν την βάση για τα υλικά και τις μεθόδους που χρησιμοποιούμε για τον έλεγχο κάθε είδους πυρκαγιάς. Το κεφάλαιο κλείνει με παρουσίαση των υιοθετημένων προτύπων στην Ελλάδα. Το δεύτερο κεφάλαιο αναλύει την πυρασφάλεια κτηρίων, Παθητική και Ενεργητική. Στην Παθητική πυροπροστασία δίνεται ιδιαίτερη έμφαση στην κατηγορία των εκπαιδευτηρίων οπού εμπίπτει το κτίριο του τμήματος των Χημικών Μηχανικών Παρουσιάζονται όλοι οι τρόποι πυροπροστασίας αλλά και τα μέσα πυρανίχνευσης και πυρόσβεσης που χρησιμοποιούνται σήμερα καθώς και τα κριτήρια επιλογής τους βάση της ισχύουσας νομοθεσίας. Στο τρίτο κεφάλαιο αποτυπώνονται οι υπάρχουσες εγκαταστάσεις του κτιρίου του τμήματος των Χημικών Μηχανικών και παρουσιάζεται φωτογραφικό υλικό από την επί τόπου αυτοψία που έγινε. Το κεφάλαιο τέσσερα είναι η μελέτη Ενεργητικής πυροπροστασίας του κτιρίου του τμήματος των Χημικών Μηχανικών που έγινε σύμφωνα με όσα προβλέπει η Ελληνική νομοθεσία. Τέλος στο παράρτημα παρουσιάζονται οι κανονισμοί πυρασφάλειας και πυροπροστασίας όπως αυτοί έχουν καθοριστεί από το Πυροσβεστικό Σώμα. Πιο συγκεκριμένα παρουσιάζεται το προεδρικό διάταγμα «Κανονισμός Πυροπροστασίας Κτιρίων (Π.Δ. 71/88)», το οποίο αποτελεί το βασικό διάταγμα σύμφωνα με το οποίο γίνονται όλες οι μελέτες πυροπροστασίας, και επισυνάπτονται τα σχέδια των αποτυπώσεων και τα σχέδια της μελέτης. / The protection of human life is a basic obligation of the state and fundamental right of the citizen. Therefore the protection of a building from fire is mandatory, especially when that building is a school that hosts hundreds of people. This thesis is intended to capture and design the Fire safety and security system of the building of Chemical Engineering. Through the process of recording, the goal of this thesis is to determine whether the mechanisms of prevention, response and firefighting of building, are sufficient to meet the basic objectives of fire protection. Those being, safety of human life and health, spreading of fire to neighboring buildings or in other apartments of the same building, safe evacuation and finally the protection of property. The first chapter provides definitions and basic concepts, presents the triangle and pyramid of fire, the causes of fires and the distinction of causes depending on the intent or fault. There is a presentation of the types and classes of fires and a description of the principles of extinguishing fire form the basis of the materials and methods used to control any kind of fire. The chapter ends with the presentation of the adopted standards in Greece. The second chapter analyzes the Passive and Active fire safety of buildings. Emphasis is given to the passive fire protection of schools which applies to the department of Chemical Engineering. Also there is a description of the ways and means of fire detection and extinguishing systems in use today and their selection criteria based on current legislation. The third chapter depicts the existing facilities of the building of the department of Chemical Engineering and photographs of the on-site inspection that was made are presented. Chapter four is the study of active Fire safety building department of Chemical Engineering, which was made according to the provisions of the Greek law. Finally in the appendix is presented the fire safety and fire regulations as laid down by the Fire Brigade. More specifically, is presented the Presidential Decree "Building Fire Safety Regulation (Decree 71/88)", which is the main decree under which all fire protections designs are made, and accompanied by the drawings and renderings of the design drawings.
48

Experimental and Numerical Modeling of Heat Transfer in Wall Assemblies

2014 April 1900 (has links)
It is critical for the construction industry to ensure that new building designs and materials, including wall and floor assemblies, provide an acceptable level of fire safety. A key fire safety requirement that is specified in building codes is the minimum fire resistance rating. A manufacturer of building materials (e.g., insulation or drywall) is currently required to perform full-scale fire furnace tests in order to determine the fire resistance ratings of assemblies that use their products. Due to the cost of these tests, and the limited number of test facilities, it can be difficult to properly assess the impact of changes to individual components on the overall fire performance of an assembly during the design process. It would be advantageous to be able to use small-scale fire tests for this purpose, as these tests are relatively inexpensive to perform. One challenge in using results of small-scale fire tests to predict full-scale fire performance is the difficulty in truly representing a larger product or assembly using a small-scale test specimen. Another challenge is the lack of established methods of scaling fire test results. Cone calorimeter tests were used to measure heat transfer through small-scale specimens that are representative of generic wall assemblies for which fire resistance ratings are given in the National Building Code of Canada. Test specimens had a surface area of 111.1 mm (4.375 in.) by 111.1 mm (4.375 in.), and consisted of single or double layers of gypsum board, stone wool insulation and spruce-pine-fir (SPR) studs. As the specimens were designed to represent a one-quarter scale model of a common wall design, with studs spaced at a centre-to-centre distance of 406.4 mm (16 in.), the wood studs were made by cutting nominal 2x4 studs (38 mm by 89 mm) into 9.25 mm by 89 mm (0.375 in. by 3.5 in.) pieces. The scaled studs were then spaced at a centre-to-centre distance of 101.6 mm (4 in.). Three types of gypsum board were tested: 12.7 mm (0.5 in.) regular and lightweight gypsum board, and 15.9 mm (0.625 in.) type X gypsum board. Temperature measurements were made at various points within the specimens during 70 min exposures to an incident heat flux of 35, 50 and 75 kW/m2 using 24 AWG Type K thermocouples and an infrared thermometer. Temperature measurements made during cone calorimeter tests were compared with temperature measurements made during fire resistance tests of the same generic assemblies and the result show a very good agreement for the first 25 min of testing at the unexposed side. A one-dimensional conduction heat transfer model was developed using the finite difference method in order to predict temperatures within the small-scale wall assemblies during the cone calorimeter tests. Constant and temperature-dependent thermal properties were used in the model, in order to study the effects of changes to materials and thermal properties on fire performance. A comparison of predicted and measured temperatures during the cone calorimeter tests of the generic wall assemblies is presented in this thesis. The model had varying degrees of success in predicting temperature profiles obtained in the cone calorimeter tests. Predicted and measured times for temperatures to reach 100C and 250C on the unexposed side of the gypsum board layer closest to the cone heater were generally within 10%. There was less agreement between predicted and measured times to reach 600C at this location, and the temperature increase on the unexposed side of the test specimen. The model did not do a good job in predicting temperatures in the insulated double layer walls. Sensitivity studies show that the thermal conductivity of the gypsum board has the most significant impact on the predicted temperature.
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The behaviour of steel-framed composite structures in fire conditions

Gillie, Martin January 2000 (has links)
Over the last decade it has become increasingly clear that the traditional methods of fire safety design can be unnecessarily conservative and therefore expensive. In 1995 a series of fire tests were carried out at Cardington, UK on a full-scale eight storey steel-concrete composite building. These tests produced an extensive body of data about the response of such structures to fire conditions and it is intended that this data be used to develop a clearer understanding of the structural behaviour involved. This thesis presents a method of analysing the behaviour of structures such as the Cardington frame using the commercial finite element package ABAQUS, with the addition of user defined subroutines; applies the method to two of the Cardington tests and analyses the results. FEAST, a suite of computer programmes that defines the behaviour of shell finite elements using a stress-resultant approach, was programmed for use with ABAQUS. The FEAST suite consists of two main programmes. The first, SRAS, is designed to model the behaviour of orthotropic plate sections at elevated temperatures. The second, FEAI, interfaces with the finite element package ABAQUS and allows realistic models of the behaviour of whole structures in fire conditions to be obtained. Phenomena modelled by FEAST include non-linear thermal gradients, non-linear material behaviour and coupling between membrane and bending forces. FEAST was used to analyse the behaviour of the Cardington Restrained Beam Test and the Cardington Corner Test. In both cases it was possible to produce a comprehensive set of results showing the variation of forces, moments and deflections in the structure under fire conditions. In addition, a number of parametric studies were performed to determine the effect of factors such as slab temperature and coefficient of thermal expansion on the behaviour of the structure. Special attention was given to the role of tensile mebrane action. The results showed that the behaviour of the heated structure was very different to that of an unheated structure. The response of the structure was shown to be very strongly governed by restrained thermal expansion and by thermal gradients. Degradation of material properties were found to have only a secondary effect on the structural behaviour.
50

A Comparison between two different Methods to Verify Fire Safety Design in Buildings

Ronstad, David January 2017 (has links)
In today’s Nordic construction industry, it is difficult for new and innovative building solutions to be introduced due to prescriptive and inflexible regulations. Trading products and services cross-border is something that could loosen the tough market, but this is not possible due to the lack of common international frameworks that is performance based with the possibility to perform fire safety engineering. This is something that the Nordic Innovation project group called Fire Safety Engineering for Innovative and Sustainable Building Solutions wants to change. By introducing a new probabilistic method to verify fire safety in buildings, with the intention to become a Nordic standard, so will hopefully parts of these problems be resolved. The fourth work package of the project includes field testing of the new method which this thesis is a part of. The idea is to asses and improve the new probabilistic approach by comparing it to an existing non-probabilistic method and introduce ameliorating recommendations. Comparison of the probabilistic method is performed against a Swedish verification process that’s based on the General recommendations on analytical design of fire safety strategy (BBRAD) by verifying fire safety in a car park, that is located below an office building, with both verification methods. The two performance-based analyses treat deviations from a prescriptive solution, performed with the Boverket’s Building Regulations (BBR), and the results of these verifications is compared. The requirements that is verified are; escape in event of fire, protection against the outbreak of fire, protection against the development and spread of fire and smoke in buildings, protection against spread of fire between buildings, possibility of rescue responses and ensuring fire resistance in the structural members. Fire safety designs and approaches for treatment of the deviations are compared and analysed which concludes in the improvement recommendation that’s been presented.  Questions that has been answered during the work process is: How do the methods treat the possibility of a fire safety design without sprinkler? What is the main difference between the two verification methods? Which improvements could be done to the new Probabilistic method?  The recommendations of improvement that has been presented is based on the work process of the probabilistic approach and the comparison with the Swedish verification process. Development of the following areas is advocated: Treatment of critical levels for evacuation scenarios  Form a common Nordic statistical database Improved guidance of how to complete the validation analysis The thesis does not include all parts that’s required in a fire safety design but will merely focus on the deviations of the pre-accepted solution. The verification is only performed on the car park, i.e. the office part of the building is not included. / I dagens nordiska byggbransch är det svårt för nya och innovativa byggnadslösningar att införas på grund av de preskriptiva och fyrkantiga regelverk som finns. Handel av produkter och tjänster över gränserna är något som kan luckra upp den tuffa marknaden, men det är svårt på grund av bristen utav gemensamma internationella regelverk som är funktionsbaserade med möjlighet till fire safety engeinnering. Det är något som ett nordiskt innovationsprojekt kallat Fire Safety Engineering for Innovative and Sustainable Building Solutions vill förändra. Genom att införa en ny probabilistisk metod för att verifiera brandsäkerheten i byggnader, med avsikten att skapa en nordisk standard, kan förhoppningsvis delar av dessa problem lösas. Det fjärde arbetspaketet inom projektet består av att testa den nya metoden, vilket denna avhandling är en del av. Tanken är att bedöma och ta fram förbättringsförslag till den nya probabilistiska metoden genom att jämföra den med en befintlig scenariobaserad metod och presentera förbättringsrekommendationer. Jämförelse av probabilistiska metoden utförs mot en svensk verifieringsprocess som baseras på Boverkets allmänna råd om analytisk dimensionering av byggnaders brandskydd (BBRAD) genom att verifiera brandsäkerheten i ett parkeringsgarage, som ligger under en kontorsbyggnad, med båda verifieringsmetoderna. De två funktionsbaserade analyserna behandlar avvikelser från en förenklad dimensionering, som är utförd enligt Boverkets Byggregler (BBR), och resultaten av dessa verifikationer jämförs. De krav som verifieras är; utrymning i händelse av brand, skydd mot uppkomst av brand, skydd mot utveckling och spridning av brand och rök i byggnader, skydd mot brandspridning mellan byggnader, möjlighet till räddningsinsats och att säkerställa bärförmåga vid brand. Brandskyddets utformning och metodernas behandling av avvikelserna jämförs och analyseras vilket konkluderar i de rekommendationer för förbättring som presenteras. Frågor som har besvarats under arbetsprocessen är: Hur behandlar metoderna möjligheten att dimensionera brandsäkerheten utan sprinklersystem? Vad är den stora skillnaden mellan de två verifieringsmetoderna? Vilka förbättringar kan göras på den nya probabilistiska metoden? Rekommendationerna till förbättring som har tagits fram är baserad på arbetsprocessen i den probabilistiska metoden och jämförelsen med den svenska verifieringsprocessen. Utveckling av följande områden förespråkas: Behandling av kritiska nivåer i utrymningsscenarion Uppställning av en gemensam statistiskdatabas för de nordiska länderna Förbättrad förklaring om hur man utför valideringarna av analysen Avhandlingen omfattar inte alla delar som behövs vid bandskyddsprojektering utan fokusera endast på avvikelserna från den förenklade dimensioneringen. Verifikationen är endast utförd på parkeringsgaraget, det vill säga kontorsdelen av byggnaden behandlas inte. / Fire Safety Engineering for Innovative and Sustainable Building Solutions

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