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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.
1

Limit state design for biodeterioration - a new paradigm for management of fungal risks in biobased building materials

Lepage, Robert 27 January 2022 (has links)
Biodeterioration is the leading cause of failure in buildings. Organic materials, key components of our built infrastructure, are particularly vulnerable to biotic attack (i.e. fungal growth) and can suffer from pre-mature failure. These failures are responsible for billions of dollars of direct damage to wooden structures in Canadian buildings. The impacts of failure can range from mild surface disfigurement, allergic reactions, mycoses, to direct life-safety concerns from compromised building structures. These impacts all have different failure modes and it is therefore prudent to consider how these failures manifest. The limit state design framework is an approach used by engineers to describe the risks of failure. It defines the probabilistic failure envelope of an inherent resistance being exceeded by a given load. The competing loads and resistances, in this case, consist of the fungal growth potential versus the intrinsic resistance of the substrate. Another key feature of limits state design is that it describes differing thresholds of failure depending on the potential impacts. This framework is desirable in application for biodeterioration in buildings. However, prior attempts to adopt these concepts into biodeterioration models have met with limited success. This dissertation is the first to effectively apply a limit state design framework to biodeterioration by considering two key states: serviceability limit state (i.e. surface fungal growth), and ultimate limit state (i.e. incipient decay). First, a database of fungal deterioration was created using Penicillium chrysogenum and Gloeophyllum trabeum fungi inoculated on jack pine (Pinus banksiana) prisms. These prisms were careful controlled for both moisture content and temperature, while minimizing ambient contamination. Photo documentation using a 20x USB microscope permitted evaluation of the surface disfigurement of the ascomycete fungus (serviceability state), and non-destructive flexural testing permitted the identification of incipient decay with the wood rotting basidiomycete (ultimate limit state). A serviceability limit state model was created using a population growth equation to describe the probability of detecting fungal growth as a function of substrate type (heartwood or sapwood), moisture content, temperature, and time. The model was contrasted with empirical tests on a mouldy roof in Vancouver, BC, and shows promising results that surpass the limitations of competing mould models. The method to develop the ultimate limit state model has been delineated in this dissertation, but further work is required. Future scopes of work are provided to address the limits and areas of uncertainty revealed by this research, but the results can help reshape the narrative of biodeterioration risk assessments for the built environment. / Graduate
2

ROBUST ESTIMATION OF RELIABILITY IN THE PRESENCE OF MULTIPLE FAILURE MODES

Adduri, Phani R. 19 December 2006 (has links)
No description available.
3

Statické řešení kostela v Brně / Static analysis of Church in Brno

Rejnart, Michal January 2018 (has links)
This diploma thesis deals with design of roof structure of the church in Brno Lesná. It is arched shell, which is symmetrical only by one axis. The roof is clamped by bond beam at supports of roof structure, which sits on a reinforced concrete walls, which transfers load to foundations. This structure is checked for the Ultimate Limit State and Service Limit State. Text part of design contains report, where is described structural system and technological proces. The structural design report contains assessment proces of designed structure.
4

Návrh silničního mostu / Design of a road bridge

Barkáč, Erik January 2020 (has links)
The subject of this diploma thesis is the design and analysis of a bridge at the R48 bypass over the Ostravica River. For this purpose, three variants of the supporting structure solution were developed from which a variant of additionally prestressed chamber girder with perpendicular walls was selected. The main task is to assess the construction for phased construction. The static calculation was drawn up according to European
5

A pre-study of the static behaviour of a single diagonal timber arch bridge

Öhgren, Lovisa, Åström, Malin January 2020 (has links)
The aim of this thesis is to study and gain more insight about the static behaviour of the three hinged single diagonal timber arch bridge in different situations. The bridge was tested for static analyses for both Ultimate Limit State and Serviceability Limit State, to investigate its behaviour and if it is possible to be built at the selected location. Furthermore, the dimensions of the elements are to be determined. Pre-studies on similar bridges have been done and their problems have been taken into account when analysing the behaviour of this bridge. Thereafter, two different designs have been constructed. The finite element software RFEM has been used in this project to be able to analyse the behaviour of the two different models. The in-plane buckling of the arch is the most critical part of the bridge and the bridge should therefore be designed regarding that. Additionally, different alternatives were suggested to reduce the deformation of the deck in the models. Finally, an optimized model is reached which consists of longitudinal beams and has an arch with a wide cross section.
6

Návrh předpjaté stropní konstrukce / Design of a prestressed slab

Juříček, Lukáš January 2018 (has links)
Diploma thesis is focused on the design of prestressed concrete membrane from the lightweight concrete. The concrete membrane is in the interaction with the bearing steel structure, which one is supported. I did only one variant of the solution, which was optimized. The goal of the design was determined the initial state of a membrane and ensure to in the end of design working life was the membrane in the compression state and the cracks couldn’t appear. The structure is modelled in the main (longitudinal) direction as a spatial frame in program ANSYS 17.2. This tool enables to perform analysis of the construction stages. The rheology is calculated manually and supplied to the model as relative strain. The whole structure is checked for ultimate limit state and serviceability limit state according to valid Eurocodes. Transverse direction is modelled by shell elements in program RFEM 5.12. Construction stages and global behaviour of the structure were analysed. The checks have been calculated manually and control in program IDEA StatiCa. The attachments of the thesis are drawings, visualisation and schemes of construction stages.
7

Nosná železobetonová konstrukce vícepodlažního objektu / Load-bearing RC structure of the multi-storey building

Petrovič, Jiří January 2019 (has links)
The Master’s thesis is focused on the analysis and design of selected members of load-bearing structure of an apartment house according to the ultimate limit states (ULS) and seviceability limit states (SLS). The calculation and the analysis was supported by design software SCIA ENGINEER 2017. Structural analysis deals with the design of the reinforced concrete floor slab of 1.PP, beams in 1.PP, selected walls in 1.NP and column in 1.PP and 1.NP. Thework beside this deals with the calculation and design of foundation of the object.
8

Železobetonová konstrukce polyfunkčního domu / Reinforced concrete structure of a multifunction building

Pohl, Martin January 2019 (has links)
The diploma thesis deals with structural solution of the reinforced structures of the polyfunctional building. The structure is designed and assessed for for ultimate limit state in accordance with ČSN EN 1992-1-1: Design of concrete structures – Part 1-1: General rules and rules for buildings.
9

Lávka pro pěší podporovaná kabely / Cable-supported pedestrian bridge

Hlava, Martin January 2015 (has links)
The purpose of the master’s thesis is about a concept of a pedestrian bridge´s bearing construction for pedestrian endorsed wires above a highway R35. The work includes a statical construction calculation of the suspended foot bridge of six spans, which has been chosen from three options. The chosen option is built of a monolithic, pre-stressed concrete board supported by suspenders, which is made by segmental elements above the fast highway. Calculation of a longitudinal direction has been made in an ANSYS application. Assembling status and cross direction of the construction has been modelled at SCIA Engineer. The construction´s recognition has been made manually expect of several towers cross-section, where the judgement has been made at IDEA StatiCa.
10

Lávka pro pěší přes řeku Berounku / Footbridge over the Berounka river

Pejčoch, Karel January 2017 (has links)
THE OBJECT OF THE MASTER THESIS IS TO DESIGN OF SUPPORTING STRUCTURE OF PEDESTRIAN BRIDGE SITUATED OVER THE RIVER OF BEROUNKA. THE THESIS CONTAINS STATIC ANALYSIS OF THE CABLE-STAYED BRIDGE WITH TWO FIELDS, WHICH WAS CALCULATED IN THREE VERSIONS .THE CHOSEN VERSION OF THE BRIDGE CONSIST OF MONOLITIC AND PRECAST CONCRETE BRIDGE DECK, WHICH IS CONSTRAINED USING PRESTRESSED CABELS AND SUPPORTED BY HANGINGS.THE CALCULATIONS OF THE LONGITUDINAL WAS PERFORMED BY COMPUTATIONAL SOFTWARE OF SCIA ENGINEERING 15.1

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