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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.
171

Návrh založení objektu / The design of building foundations

Machů, Michal January 2018 (has links)
The subject of this work is a proposal of foundation, followed by an assessment for a production hall. Options will be discussed and compared against each other. The premises are situated in an area where great layers of gravel are found. A project of foundations founding will be performed according to Eurocode 7. Designing of geotechnical constructions which are based on given characteristic of presented soils. As a part of this work also is an appropriate drawing documentation.
172

Administrativní budova v Brně / The administrative object in Brno

Muňko, Matej January 2019 (has links)
The subject of this work is a new administrative building in Brno, district Brno – Stred. The aim of this work is to create documentation for realization. Building has twelve floors, while every floor is rotated by 5° relative to the previous floor counterclokwise. Final rotation between the first and the last floor is 60°. On the first floor there is a restaurant, on the next eleven floors there are administrative spaces. Building is without basement and has a single-layer flat roof. The foundations are made from a system of piles, which co-work with the waterproof foundation slab. Whole construction system is made from cast-in-place reinforced conrete.
173

Analýza a ošetření rizik technologického procesu / Risk analysis and treatment of the technological process

Vengřínová, Hana January 2016 (has links)
This diploma thesis deal with analysis and evaluation risks of the technological process of bored piles. Risks are divided into divisions of quality, environmental and safety. Subsequently conducted a risk analysis. The risk assessment was made by following methods - Risk Matrix, FMEA (Analysis Failure Modes and Effects) and Pareto chart. With the help of these methods are assessed identified risks and proposed appropriate measures for risk retention.
174

Design and execution of energy piles : Validation by in-situ and laboratory experiments / Dimensionnement et exécution de pieux énergétiques : Validation par essais in-situ et en laboratoire

Vasilescu, Andreea-Roxana 08 July 2019 (has links)
Les pieux énergétiques représentent une solution alternative intéressante, face à l’accroissement des besoins mondiaux en énergie et à la réduction de l’utilisation des énergies fossiles. L’objectif principal de la thèse est d’identifier et de quantifier les principaux facteurs influençant le dimensionnement des pieux géothermiques, qui sont impactés par les changements de température des pieux lors de leur activité. Pour ce faire, ce travail de thèse a été dressé en 3 campagnes expérimentales, dont deux à échelle réelle : (i) une première campagne à chargement thermomécanique contrôlé (Marne La Vallée), (ii) une seconde campagne en conditions d’utilisation réelles sous une station d’épuration (Sept Sorts) et (iii) une troisième campagne à l’échelle du laboratoire grâce à une nouvelle machine de cisaillement direct d’interface permettant l’étude du comportement thermo mécanique des interfaces sol-structure. Ces trois campagnes expérimentales ont pour but de quantifier l’effet de la température et des cycles de température sur le comportement des pieux énergétiques. Les premiers résultats expérimentaux de la campagne de Sept Sorts ont ensuite été simules dans le code LAGAMINE via la méthode des éléments finis, afin d’adopter une approche complémentaire permettant de mieux appréhender la réponse thermomécanique de ce type de pieu lors de l’activation géothermique. et (iii) une troisième campagne à l’échelle du laboratoire grâce à une nouvelle machine de cisaillement direct d’interface permettant l’étude du comportement thermo mécanique des interfaces sol-structure. Ces trois campagnes expérimentales ont pour but de quantifier l’effet de la température et des cycles de température sur le comportement des pieux énergétiques. Les premiers résultats expérimentaux de la campagne de Sept Sorts ont ensuite été simules dans le code LAGAMINE via la méthode des éléments finis, afin d’adopter une approche complémentaire permettant de mieux appréhender la réponse thermomécanique de ce type de pieu lors de l’activation géothermique. / Energy piles, also called thermo-active piles, are an alternative solution to the increase in the global energy demand as well as in mitigating socio-economical stakes concerning the increase of energy costs due to fossil fuels. Energy piles are double purpose structures that allow transferring the loads from the superstructure to the soil and that integrate pipe circuits allowing heat exchange between the pile and the surrounding ground. The objective of this thesis is to identify and quantify the principal parameters involved in the geotechnical design of pile foundations impacted by temperature changes associated with geothermal activation. For this purpose, this research work was organized in 3 experimental campaigns: (i) A full scale load controlled test at Ecole des Ponts Paris-Tech, (ii) Full scale energy piles monitoring under real exploitation conditions at Sept Sorts, (Seine et Marne, France), (iii) Laboratory tests in order to assess the effect of temperature and temperature cycles at the soil-pile interface. The experimental results are used to estimate the effect of geothermal activation of a pile foundation, on its bearing capacity as well as on its long-term exploitation. Finally, preliminary numerical simulations were performed using a thermo-hydro mechanical model, using the finite element method code LAGAMINE able to capture the main phenomena.
175

Lateral Resistance of 24-inch Statically Loaded and 12.75-Inch Cyclically Loaded Pipe Piles Near a 20-ft Mechanically Stabilized Earth (MSE) Wall

Wilson, Addison Joseph 03 December 2020 (has links)
Installing load bearing piles within the reinforcement zone of mechanically stabilized earth (MSE) retaining walls is common practice in the construction industry. Bridge abutments are often constructed in this manner to adapt to increasing right-of-way constraints, and must be capable of supporting horizontal loads imposed by, traffic, earthquakes, and thermal expansion and contraction. Previous researchers have concluded that lateral pile resistance is reduced when pile are placed next to MSE walls but no design codes have been established to address this issue. Full –scale testing of statically applied lateral loads to four 24”x0.5” pipe piles, and cyclically applied lateral load to four 12.75”x0.375” pipe piles placed 1.5-5.3 pile diameters behind a 20-foot MSE wall was performed. The MSE wall was constructed using 5’x10’ concrete panels and was supported with ribbed strip and welded wire streel reinforcements. The computer software LPILE was used to back-calculate P-multipliers for the 24” piles. P-multipliers are used to indicate the amount of reduction in lateral resistance the piles experience due to their placement near the MSE wall. Previous researchers have proposed that any pile spaced 3.9 pile diameters (D) or more away from the MSE wall will have a P-multiplier of 1; meaning the pile experiences no reduction in lateral resistance due to its proximity to the wall. P-multipliers for piles spaced closer than 3.9D away from the wall decrease linearly as distance from the wall decreases. P-multipliers for the 24” piles spaced 5.1D, 4.1D, 3.0D, and 2.0D were 1, 0.84, 0.55, and 0.44 respectively. Lateral resistance of the 12.75” cyclically loaded piles decreased as the number of loading cycles increased. Lateral resistance of the piles when loads were applied in the direction of the wall was less than the lateral resistance of the piles when loads were applied away from the wall at larger pile head loads. The maximum tensile force experienced by the soil reinforcements generally occurred near the wall side of the pile face when the lateral loads were applied in the direction of the wall. Behind the pile, the tensile force decreased as the distance from the wall increased. Equation 5-4, modified from Rollins (2018) was found to be adequate for predicting the maximum tensile force experienced by the ribbed strip reinforcements during the static loading of the 24” pipe piles, particularly for lower loads. About 65% of the measured forces measured in this study fell within the one standard deviation boundary of the proposed equation.
176

Pre-Columbian Cultivation of Agave Species Through Rock Mulching: Potential for Modern Applications

Ortiz Cano, Hector Genaro 30 July 2021 (has links)
As global temperatures rise, cultivation of C3 and C4 crops in arid and semi-arid regions will face major challenges in producing biomass for billions of people. Conventional agricultural techniques that require copious irrigation will need to be complemented with dryland-farming techniques and drought-tolerant crops, such as those from the Agave genus, which use CAM photosynthesis. In the past and present, humans from arid and semi-arid regions of America have maintained a symbiotic relationship using and cultivating Agave (Agavoideae, Asparagaceae). In pre-Columbian times, Native Americans from arid regions relied on Agave cultivation as a subsistence crop to produce food, medicine, and fiber. The Hohokam in the Sonoran Desert cultivated Agave plants using rock mulching, also known as rock piles. This technique enabled the Hohokam to extensively cultivate Agave despite the limited rainwater available in the harsh Sonoran Desert. Although there are several decades of archaeological research for documenting the history of rock piles and Agave in the region beginning in the late 1970s, few studies have addressed the modern application of rock piles to cultivate Agave. Our research employed a multidisciplinary approach to bridge the historic use of rock piles to cultivate Agave with the potential application of rock piles for modern cultivation. In addition to summarizing what is known about the archaeology of Hohokam rock piles, we compiled an extensive review of the literature available on the agroecology, physiology, and natural history of Agave. We described key aspects associated with the hydrology and physical properties of Hohokam rock piles that can bolster Agave CAM photosynthesis in dry regions. We found that the use of rock piles is a feasible means of cultivating Agave under hot and dry conditions in arid regions. In addition, we used an ecological niche modeling approach and field data from Hohokam rock-pile sites and current Agave fields to assess the potential environments where rock piles could be used to cultivate Agave plants in Arizona, USA and Sonora, Mexico. We also combined an experimental archaeology approach with experimental plant physiology where we surveyed Hohokam rock-pile fields at archaeological sites to collect information about the composition of rock piles. We then created a rock-pile field where we evaluated and observed the effects of rock piles on Agave CAM utilization, mainly nocturnal CO2 uptake of Agave. Our results indicated that rock piles provide direct insulation to root systems, which indirectly benefited Agave carbon uptake and reduced temperature and drought stress. Although more agronomic research about rock pile use is needed, our research suggests that rock piles can be applied to cultivate Agave because of the physiological benefits provided such as increasing nocturnal total CO2 uptake. In addition, the suitability of rock piles in the U.S borderlands indicates that rock piles can be applied beyond the regions where they were used by the Hohokam in pre-historic times.
177

Investigating the Behavioral Factors that Influence Regional Lithic Assemblage Variability in the Upper Basin, Northern Arizona

Phillips, Emily P. 25 July 2019 (has links)
No description available.
178

Assessment of time-dependent capacity of driven piles in Ohio soils

Heron, Matthew Joseph 30 May 2019 (has links)
No description available.
179

RELIABILITY-BASED DESIGN AND QUALITY CONTROL OF DRIVEN PILES

Yang, Luo 05 October 2006 (has links)
No description available.
180

Full-Scale Lateral-Load Tests of a 3x5 Pile Group in Soft Clays and Silts

Snyder, Jeffrey L. 15 March 2004 (has links) (PDF)
A series of static lateral load tests were conducted on a group of fifteen piles arranged in a 3x5 pattern. The piles were placed at a center-to-center spacing of 3.92 pile diameters. A single isolated pile was also tested for comparison to the group response. The subsurface profile consisted of cohesive layers of soft to medium consistency underlain by interbedded layers of sands and fine-grained soils. The piles were instrumented to measure pile-head deflection, rotation, and load, as well as strain versus pile depth.

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