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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.
191

Polyfunkční dům / Multifunctional Building

Velecký, Tomáš January 2020 (has links)
This diploma thesis is focused on design cast-in-place reinforced concrete structure multi-storey multifunctional building according to the source material. Specifically, foundation slab and external wall in B1 taking into account the waterproofness of the construction. Then staircase, column in lowest storey and two floor slab are designed as selected load-bearing structure. Elements are dimensioned according to ČSN EN 1992-1-1: Design of concrete structures - general rules and rules for building structures. In the drawing part of the diploma thesis are drawn drawings of the shapes and reinforcement.
192

Hotel v Luhačovicích / Hotel in Luhačovice

Tejzr, Martin January 2020 (has links)
The final thesis is focused on a newly-built hotel with wellness in Luhačovice. Luhačovice is a spa town in the region of Zlín. The plot is situated on the outskirts of the town in a mildly built-up area. The terrain is sloping with a view of the town. The building is divided into three operating parts – wellness, restaurant with café and premises for temporary accomodation.The structure is a four-story building with a cellar. The building foundations are based on the reinforced concrete foundation slab. The load-bearing structures of the basement and the ground floor are formed by reinforced concrete walls complemented by reinforced concrete columns. Upper storeys are designed in the system of Porotherm. The floor structure is cast-in-place reinforced concrete. The building is roofed with green roof.
193

Monolitický vícepodlažní stěnový objekt / Monolithic multi-storey wall building

Vymazal, Jakub January 2015 (has links)
Final thesis with tittle: "Monolithic multi-storey wall building" is processeed as a project documentation according to valid assesment. The object is located in the city of Boskovice, 35 Hybešova street. Its ground plan dimensions are 52,8m x 12,5m. Total height of object is 22,3m including roof-wall, measured from the level of base chink. There are enclosed balconies on the south direction. Movement between floors is ensured by 2-flighted stairs. Object is It is made of reinforced concrete. It is designed as 6-floor bulding with a flat roof. The main supporting construction is created by system of walls and reciprocally asigned ceilings, which are sticked together. Walls are designed as pillars. The building is assigned to a belt bases. Module dimensions are 8,7m in longitudinal direction and 5,2m in transversal direction. Height dimension is 3,0m. The thesis is dealing with the 1st upper floor.
194

Nosná železobetonová konstrukce vícepodlažního objektu / Structure of the multi-storey of reinforced concrete building

Lochman, Ondřej January 2012 (has links)
The Master´s thesis subject is a design and an estimation of the load-bearing structure of a multi-storeyed building. The structure has a miscellaneous ground-plan shape consisting of three rectangular tracts and it is placed in the building basement under the ground level. The load-bearing structure involves walls and a floor slab which rises up vertically closer to the ground level in the central tract. Among further components being solved belong stairs, basement slab and beam. The load-bearing structure is solved monolithically as steel concrete component.
195

Návrh vybraných prvků železobetnové konstrukce / Design of selected elements of reinforced concrete structure

Klust, Vojtěch Unknown Date (has links)
Diploma thesis deals with the desing of reinforced two way concrete foundation slab in three variants. In the first variant is slab of constant thickness. In the second variant is haunched slab. In the third variant is slab with piles. The thesis includes a structural design as well as drawings. All calculations were performed in accordance with applicable standards. For the design was used program SCIA Engineer 19.1.
196

Statické řešení parkovacího domu / Static solution of parking house

Tvrzník, Jakub Unknown Date (has links)
The diploma thesis is focused on the design of the supporting structure of a multi-storey parking house. Part of the work is also a search of three parking houses in our country and in Slovakia. The content of the work is a preliminary design of 3 variants of a typical ceiling structure. Subsequently, one variant is selected and processed in detail. A flexurally supported slab-wall model was created in Scia Engineer for the analysis of the structure. Selected structural elements were modeled separately. Additional assessment is performed in GEO, FINE, IDEA Statica, JORDAHL and MS Excel software.
197

BRIDGE END SETTLEMENT EVALUATION AND PREDICTION

Zhang, Jiwen 01 January 2016 (has links)
A bridge approach is usually built to provide a smooth and safe transition for vehicles from the roadway pavement to the bridge structure. However, differential settlement between the roadway pavement resting on embankment fill and the bridge abutment built on more rigid foundation often creates a bump in the roadway. Previous work examined this issue at a microscopic level and presented new methods for eliminating or minimizing the effects at specific locations. This research studies the problem at a macroscopic level by determining methods to predict settlement severity to assist designers in developing remediation plans during project development to minimize the lifecycle costs of bridge bump repairs. The study is based on historic data from a wide range of Kentucky roads and bridges relating to bridge approach inspection and maintenance history. A macro method considering a combination of maintenance times, maintenance measures, and observed settlement was used to classify the differential settlement scale as minimal, moderate, and severe, corresponding to the approach performance status good, fair, and poor. A series of project characteristics influencing differential settlement were identified and used as parameters to develop a model to accurately predict settlement severity during preliminary design. Eighty-seven bridges with different settlement severities were collected as the first sample by conducting a survey of local bridge engineers in 12 transportation districts. Sample two was created by randomly selecting 600 bridges in the inspection history of bridges in Kentucky. Ordinal and/or multinomial logistic regression analyses were implemented to identify the relationships between the levels of differential settlement and the input variables. Two predictive models were developed. Prediction of bridge approach settlement can play an important role in selecting proper design, construction, and maintenance techniques and measures. The users can select one or two models to predict the approach settlement level for a new bridge or an existing bridge with different purposes. The significance of this study lies in its identification of parameters that had the most influence on the settlement severity at bridge ends, and how those parameters interacted in developing of a prediction model. The important parameters include geographic regions, approach age, average daily traffic (ADT), the use of approach slabs, and the foundation soil depth. The regression results indicate that the use of approach slabs can improve the performance of approaches on mitigating the problem caused by differential settlement. In addition, current practices regarding differential settlement prediction and mitigation were summarized by surveying the bridge engineers in 5 transportation districts.
198

Magmatic response to the evolving New Zealand Margin of Gondwana during the Mid-Late Cretaceous

Tappenden, Vanessa Elizabeth January 2003 (has links)
The Mount Somers Volcanic Group (MSVG) and Mandamus Igneous Complex (MIC) are the magmatic manifestations of the transition from convergence to extension at the Gondwana margin, which culminated in the separation of New Zealand from Australia and Antarctica. The MIC has been correlated both geochemically and temporally with the Central Marlborough Igneous Province (CMIP). The MSVG and CMIP are located in the Eastern Province of New Zealand. The MSVG is restricted to the Rakaia terrane, whereas the CMIP is restricted to the Pahau terrane. The Rakaia and Pahau terranes are thick accretionary complexes, which were strongly deformed as a result of prolonged subduction at the Gondwana margin. The Pahau terrane is the younger of the two and continued to be deposited and deformed until the abrupt cessation of subduction, which in the Marlborough sedimentary record occurred in the Motuan (100 - 105 Ma). Following the cessation of subduction, after an interval of 2-7 Ma of relative quiescence and subsidence of the Pahau terrane, the MSVG and MIC were erupted/emplaced. The production of MSVG and MIC magmas occurred simultaneously and the activity was of short-lived duration. SHRIMP geochronology yielded crystallisation ages of 97.0 ± 1.5 Ma to 98.0 ± 1.2 Ma from zircons separated from MSVG rhyolites. The SHRIMP ages are within error of the previously published Rb-Sr age for the MIC. The SHRIMP geochronology also confirmed the presence of inherited zircons which yielded ages consistent with their derivation from the Rakaia terrane. Ar-Ar geochronology confirmed the coeval nature of the MSVG and MIC magmatism, but yielded consistently younger ages (94.5 ± 3 Ma for the MSVG and 94.2 ± 1.7 Ma for the MIC). The systematic differences in ages obtained by SHRIMP and Ar-Ar are believed to be method-dependent. The MSVG comprises a calc-alkaline volcanic assemblage, which ranges in composition from basaltic-andesite lavas (SiO₂ = 54.5%) to high-silica rhyolites and ignimbrites (SiO₂ ≤ 78.1%). The MSVG had an original extent of at least 18 000 km². The magmas from the MSVG had high LILE/HFSE, high LILE/REE and moderately high LREE/HFSE which are characteristic of subduction derived magmas. Geochemical modelling suggests that the MSVG magmas were formed from partial melting of a subduction-modified mantle wedge, with high degrees of crustal assimilation. The assimilant had an isotopic composition similar to that of the Rakaia terrane, which is consistent with the geological setting of the MSVG. The MSVG has ⁸⁷Sr/⁸⁶Sri from 0.7055 to 0.7100 and ¹⁴³Nd/¹⁴⁴Ndi from 0.51254 to 0.51230 (ɛNd +0.5 to -4.2), which reflects varying degrees of contamination by Rakaia terrane. Radiogenic isotope modelling suggests that the MSVG end-members were derived from the same parent magma, which evolved through AFC processes from basaltic-andesite to rhyolite. The modelling strongly suggests that assimilation played a lesser role in the petrogenesis of the Malvern Hills magmas than in the petrogenesis of the other units. AFC modelling requires the degree of assimilation to increase as the magmas evolved. Oxygen isotope data are consistent with high degrees of crustal assimilation, and may indicate that the assimilant had higher ¹⁸O characteristics than the Rakaia terrane samples analysed. The MIC is an alkaline suite which ranges in composition from basalt and gabbro to syenite, trachyte and phono-tephrite. The MIC is interpreted to have formed from enriched asthenospheric mantle, with a composition similar to HIMU (²⁰⁶Pb/²⁰⁴Pbi ranges from 19.2 to 20.3). The samples range in isotopic composition from ⁸⁷Sr/⁸⁶Sri = 0.7030 to 0.7036, ¹⁴³Nd/¹⁴⁴Ndi = 0.51275 to 0.51268 (ɛNd +4.6 to +3.3). The range in isotopic composition is due to varying degrees of contamination by Pahau terrane, which reaches a maximum of 25% but in most samples is < 10%. The MIC is contaminated to a much lesser extent than the MSVG which is interpreted to be related to the thinner nature of the Pahau crust in the mid-Cretaceous. The latest phases of activity in the MIC were subjected to lower degrees of contamination which is interpreted to reflect the passage of magmas through pre-existing pathways. The onset of MSVG and CMIP magmatism coincided with the initiation of major rift-related depositional basins, and the eruption of the MSVG is demonstrably associated with normal faulting. The tectonic trigger responsible for the sudden onset of magmatism and rifting in the Eastern Province terranes was the detachment of the previously subducting slab following the cessation of subduction due to the arrival of the Hikurangi Plateau at the margin and the subsequent stalling of the Pacific spreading centre. The capture of the Gondwana margin led to the propogation of extension into the margin by the divergent Pacific plate. The ensuing extension aided the detachment of the subducting slab beneath the Eastern Province terranes. The slab-detachment promoted decompression melting of the sub-lithospheric mantle wedge to produce the MSVG magmas and triggered the ascent of asthenospheric mantle through the slab window, which melted through decompression to produce the CMIP magmatism. The asthenospheric mantle tapped by the slab detachment episode was highly enriched relative to N-MORB and is akin to the similar age HIMU-OIB affinity melts documented from Antarctica and Australia. The short-lived duration of activity is typical of slab-detachment related magmatism which occurs as a passive response to plate reconfiguration. The similarity in geochemistry of the MIC with OIB-affinity igneous centres in Australia and Antarctica implies an enriched mantle domain of large geographical extent. The distribution of relatively small volumes of OIB magmatism is suggestive of a fossil plume component, which was tapped in response to lithospheric extension producing relatively short-lived HIMU magmatism. The same fossil plume component has previously been implicated in the formation of the Cenozoic West Antarctic Rift System and may be responsible for the late Cretaceous magmatism in the Chatham Islands and Tertiary volcanics of the South Island of New Zealand.
199

Structural and Thermal Behaviour of Insulated FRP-Strengthened Reinforced Concrete Beams and Slabs in Fire

Adelzadeh, Masoud 17 September 2013 (has links)
Despite the superior properties of Fibre Reinforced Polymer (FRP) materials, the use of FRPs in buildings is limited. A key cause of concern for their use in buildings arises from their poor performance in fire occurrences. This thesis presents the results of fire performance of Reinforced Concrete (RC) beams and slabs strengthened with externally bonded FRP sheets. The performance and effectiveness of insulation materials and techniques are also investigated in this thesis. Two full-scale reinforced concrete T-beams and two intermediate-scale slabs were strengthened in flexure with carbon and glass fibre reinforced polymer sheets and insulated with a layer of spray-on material. The T-beams and slabs were then exposed to a standard fire. Fire test results show that fire endurances of more than 4 h can be achieved using an appropriate insulation system. Tests were performed in order to understand the behaviour of FRP concrete bond at high temperatures. An empirical model was then formulated to describe the bond strength deterioration due to temperature rise. Innovative measurement techniques were employed throughout the experiments to measure important observables like strain and temperature. Meanwhile, the effectiveness and practicality of techniques such as Fibre Optic Sensing (FOS) and Particle Image Velocimetry (PIV) for high temperature applications were investigated. A numerical finite-volume heat transfer model was developed to simulate the heat transfer phenomenon. The validity of the numerical model was verified by comparing the results with the results from the fire tests. By using this model, parametric analyses were performed to investigate the effect of different fire scenarios on the performance of the insulated beams. To simulate the structural performance of the T-beams a numerical model which was capable of predicting stresses and strains and deflections of a heated beam was developed. The model is capable of incorporating the effects of axial forces in the response of a restrained beam. This model was verified and used in combination with the thermal model to simulate the deflections of T-beams in fire. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-09-17 15:11:16.185
200

Fukttillstånd i betongplatta på mark : Ett experimentellt försök att jämföra teori med praktik

Selén, Niklas, Söderström, Tom January 2017 (has links)
When casting the slab in a slab-on-ground structure most of the drying will occur through the surface of the slab, which is in contact with the air. This will create a non-uniform internal moisture distribution. With the top of the slab drying faster it will also have a faster shrinkage due to drying, which in turn leads to stress in the surface layers of the slab as these wants to contract. With the slab wanting to assume a curled geometry, but being restricted by external loads and self-weight, cracks will usually appear in the surface (Lange, Lee &amp; Liu, 2011).  A concrete slab-on-ground does not dehydrate the same way as, for example, floor bellows or wall elements which has the same climate on both sides. The ground beneath a heated building standing on a slab-on-ground structure is warm and moist with a relative moisture close to 100%. After carefully examining moisture damaged slab-on-ground structures it was concluded that the temperature and moisture behavior in this type of structure is more complicated than earlier presumed. In an attempt to broaden the basis of knowledge about humidity conditions under a concrete slab-on-ground structure, measurements were performed on an existing slab.  The Council for Construction Competence (Rådet för ByggKompetens, RBK) sets the industry standard regarding moisture measurement in Sweden. In 2017 the method recommended by RBK for moisture measurement in concrete includes drilling a hole in the slab, sealing it with a plastic pipe and mounting the sensor inside. This is the method that was used for measurements in this paper. Three different measurement locations in the slab along with two sensors mounted at every location was used to gather data.  The results from the measurements show that the relative humidity near the bottom of the slab is close to 100%. The results from the sensors range from 90% to 100% RH with the majority of the results very close to 100% RH. The results discovered in this paper supports the assumption that the ground beneath a slab-on-ground structure is close to 100% RH. / Vid gjutning av en betongplatta på mark sker uttorkning främst genom ovansidan av plattan. De övre skikten av betongen får en snabbare uttorkning än de undre skikten, detta tillsammans med den krympning som sker under uttorkningen skapar spänningar i betongplattan. Fenomenet gör att plattan vill böja upp sig i kanterna men på grund av egentyngd samt laster ovanifrån uttrycker sig spänningarna istället som sprickor på ovansidan (Lange, Lee &amp; Liu, 2011). Uttorkning av en betongplatta på mark skiljer sig från uttorkning av t.ex. väggelement och mellanbjälklag som har samma klimat på bägge sidor. Marken under en uppvärmd byggnad med grundkonstruktionen platta på mark antas vara varm och fuktig med en relativ fukthalt nära 100 %. Efter noggrann undersökning av fuktskadade platta på mark konstruktioner har det visat sig att temperatur- och fuktbeteende i dessa konstruktioner är mer komplicerade än tidigare förmodat. För att bredda underlaget för de fuktförhållanden som råder i underkant av en betongplatta på mark utfördes mätningar i en befintlig betongplatta. Rådet för ByggKompetens, RBK är de som bestämmer branschstandarden inom fuktmätning i Sverige. Från 2017 är den enda metoden för fuktmätning i betong som RBK rekommenderar en metod där ett hål borras i betongplattan, tätas med ett foderrör och en RF-givare monteras inuti. Denna metod användes vid mätningarna i detta arbete. Tre olika mätpunkter med två RF-givare vid varje mätpunkt har använts vid mätningarna. Resultaten från mätningarna visar på att den relativa fuktigheten i betongplattans underkant är nära 100 %. Resultaten från givarna varierade mellan 90 % till 100 % RF där majoriteten av resultaten ligger väldigt nära 100 % RF. I och med dessa resultat styrker denna rapport antagandet om att marken under en platta på mark har en RF på 100 % eller väldigt nära.

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