Unbound granular materials (UGMs) used in the base and sub-base layers of flexible pavements play a significant role in the overall performance of the structure. Proper understanding and characterization of the deformation behaviour of UGMs in pavement structures are, therefore, vital for the design and maintenance of flexible pavements. In this study, the resilient deformation (RD) and the permanent deformation (PD) behaviour of UGMs were investigated for the better understanding and improved modelling of these deformation characteristics. The study is based on a series of repeated-load triaxial (RLT) tests carried out on several UGMs commonly used in pavement structures. Here, the influences of stress level and moisture content - two of the most significant factors affecting the deformation behaviour of UGMs - were analysed. The effects of the grain size distribution and the degree of compaction were also considered. The study on the RD behaviour indicated that the resilient stiffness (MR)of UGMs increases with the increased bulk stress level, which can be satisfactorily described by the k-θ model. Moisture was found to negatively impact the MR as long as the deformation was mostly resilient with a negligible amount of accumulated PD. Analysis of the influence of moisture on the parameters k1 and k2 of the k-θ model showed that k1 decreases with increased moisture and k2 is relatively insensitive to moisture. Based on these observations, a simple model was developed for the impact of moisture on MR. The performance of this model was comparable to an existing moisture dependent MR model. In contrast, it was further observed that at the later stages of the RLT tests, after a relatively large number of load applications, the MR increased with increased moisture up to the optimum moisture content. This occurred when the RD was accompanied by a significant amount of PD. Further investigation suggested that moisture aided the post-compaction (PC) and possible particle rearrangement that resulted in the increased PD and increased MR. In this case k1 decreased, whereas k2 increased, with increased moisture. The existing MR-moisture model did not work for this behaviour. This suggests that the effect of PC on MRshould be considered in modelling. However, although not explored in this study, it may be possible to simulate this effect of increase in MR with increased moisture due to PC using the proposed model if k2 is expressed as a function of moisture. The PD characteristics of UGMs were investigated based on the multistage (MS) RLT test. In contrast with the single stage (SS) RLT test, the MS RLT test accounts for the effect of stress history and enables a comprehensive study of the material behaviour under cyclic stresses of various magnitudes. Since the existing PD models cannot be directly applied for the MS loading procedure, a general formulation based on the time hardening concept was derived that can be used to extend the models for the MS loading conditions. Based on this formulation, some of the current models were calibrated and their performance in predicting the PD behaviour in MS RLT tests was compared. The investigation regarding the impact of moisture on PD showed that moisture significantly increases the accumulation of PD. Generally, materials with finer grading showed more sensitivity to moisture with regards to both PD and RD. To characterize the impact of moisture, moisture sensitivity of different grain size distributions and the impact of the degree of compaction on PD with reduced effort, a simple model was proposed. Unlike some of the well-performing existing models, this model can be calibrated using a single MS RLT test without requiring any separate static failure triaxial tests. This model was validated using the MS RLT test data with satisfactory results. The sensitivity of the parameters of this model was studied with respect to moisture content, degree of compaction and grain size distribution. Some reasonable trends for the sensitivity of the parameters to these influential factors were obtained, which suggests that these may be further developed to incorporate into the model. / <p>QC 20150325</p>

The thesis investigates the formal semantics of temporal indexical expressions in English. Examples of such expressions include now, tomorrow and last year. In the past, research has concentrated on instances of such expressions which have two major properties. These indexicals are sensitive to extralinguistic context, and while they do possess descriptive meaning, that meaning does not appear within the propositions which correspond to utterances of the sentences which contain the indexicals. The thesis argues that this line of research has neglected a significant body of natural language evidence in which indexicals display rather different behaviour. We term indexicals from the first group unbound, and indexicals from the second group bound. Given these two domains of indexical evidence, the thesis sets out to achieve three primary aims. The first aim is to provide a formal semantic representation of both bound and unbound indexicals which systematically relates them, while distinguishing them from non-indexical expressions. To establish this aim, we informally investigate the relationship between the two types of indexical, and propose a unifying generalisation. This generalisation is then embedded within an existing but novel semantic system, due to Richards, called IQ. IQ is an interval-based semantics for tenses and temporal quantifiers in English which makes use of double-indexing. IQ must be modified so as to properly accommodate indexicals. With a new representation in hand, we demonstrate that the thesis can adequately treat both types of indexical occurrence. The second aim of the thesis is to assess the effects of the incorporation of the two types of indexical on the semantic entities of IQ. The propositions of IQ already include two major types: value free and value specific. Using the new representation of indexicals, the thesis shows that there are further varieties of the value free proposition. These propositions are then compared with Kaplan's contents, Frege's thoughts and Russell's propositions. The final aim is to establish a rigorous formulation of a fragment of the version of IQ derived in the thesis. Given this formulation, it is possible to assess its position relative to a landmark in the logic of indexicals. Using mathematical techniques, the thesis proves that the tense operators and indexical operators of the final version of IQ have particular properties which distinguish them from those in other indexical logics also based on double-indexing.

Im Rahmen der Dissertation wurde untersucht, wie die Wasserdurchlässigkeit von ToB unter Baustellenbedingungen geprüft werden kann und welcher Zusammenhang zwischen Verformungsmodul und Wasserdurchlässigkeit besteht und ob diese Eigenschaften baustofftech-nisch oder bautechnologisch beeinflussbar sind. Dazu wurden bei einer Vielzahl von Baumaßnahmen beim Ausbau des Autobahnnetzes in den neuen Bundesländern baubegleitende Messungen auf Tragschichten durchgeführt. Außerdem wurden auf verschiedenen ToB-Versuchsfeldern in einem Lysimeter Vergleichsuntersuchungen mit den Prüfgeräten Tropf-, Doppelring- und Standrohr-Infiltrometer durchgeführt. Außerdem fanden Untersuchungen auf zwei Versuchs-Baustraßen in Schotterwerken statt. Untersucht wurde zunächst, wie sich die Variation der Parameter Korngrößenverteilung, Kornform und Sandtyp sowie Verdich-tungswassergehalt und Verdichtungsgrad auf die Eigenschaften der ToB im Neuzustand auswirken. Es wurde außerdem Untersucht, inwieweit sich ein Zusammenhang darstellen lässt zwischen dem Anstieg der Tragfähigkeit (Ev2-Wert) über eine bestimmte Schichtdicke der ToB und ihrer Wasserdurchlässigkeit.

The purpose of this study was to improve flexible base course performance within the state of Texas while reducing TxDOT’s testing burden. The focus of this study was to revise the current specification with the intent of providing a “performance related” specification while optimizing sample sizes and testing frequencies based on material variability. A literature review yielded information on base course variability within and outside the state of Texas, and on what tests other states, and Canada, are currently using to characterize flexible base performance. A sampling and testing program was conducted at Texas A&M University to define current variability information, and to conduct performance related tests including resilient modulus and permanent deformation. In addition to these data being more current, they are more representative of short-term variability than data obtained from the literature. This “short-term” variability is considered more realistic for what typically occurs during construction operations. A statistical sensitivity analysis (based on the 80th percentile standard deviation) of these data was conducted to determine minimum sample sizes for contractors to qualify for the proposed quality monitoring program (QMP). The required sample sizes for contractors to qualify for the QMP are 20 for gradation, compressive strength, and moisture-density tests, 15 for Atterberg Limits, and 10 for Web Ball Mill. These sample sizes are based on a minimum 25,000 ton stockpile, or “lot”. After qualifying for the program, if contractors can prove their variability is better than the 80th percentile, they can reduce their testing frequencies. The sample size for TxDOT’s verification testing is 5 samples per lot and will remain at that number regardless of reduced variability. Once qualified for the QMP, a contractor may continue to send material to TxDOT projects until a failing sample disqualifies the contractor from the program. TxDOT does not currently require washed gradations for flexible base. Dry and washed sieve analyses were performed during this study to investigate the need for washed gradations. Statistical comparisons of these data yielded strong evidence that TxDOT should always use a washed method. Significant differences between the washed and dry method were determined for the percentage of material passing the No. 40 and No. 200 sieves. Since TxDOT already specifies limits on the fraction of material passing the No. 40 sieve, and since this study yielded evidence of that size fraction having a relationship with resilient modulus (performance), it would be beneficial to use a washed sieve analysis and therefore obtain a more accurate reading for that specification. Furthermore, it is suggested the TxDOT requires contractors to have “target” test values, and to place 90 percent within limits (90PWL) bands around those target values to control material variability.

No substantial studies, at least to my knowledge, have yet been dedicated either to Milton's or to Shelley's extensive poetic use of the grotesque. This omission surprises me, especially given the voluminous critical attention both authors receive. Neither Milton nor Shelley's grotesquerie can be viewed as the basis of artistic method or artistic achievement as we might with, say, Rabelais, or Poe, or even Kafka. And neither Milton nor Shelley is self-consciously an artist of "the grotesque." In fact, Milton, from his seventeenth century perspective, would scarcely have regarded the term as being applicable to literary criticism at all. And as a late Romantic, Shelley defined himself rather as a poet of the imagination. Nonetheless I will show that both artists avail themselves of a grotesque aesthetic to achieve some of their most powerful and provocative poetry: we may here consider, for instance, Milton's memorable descriptions of the incongruities of Hell and the deformities of its fallen denizens in Paradise Lost, or Shelley's Gothic touches and his perplexing distortion of conventional linguistic and dramatic form in Prometheus Unbound. / Aside from general considerations of the grotesque in these texts, I will especially focus on how Milton's and Shelley's uses of the grotesque mode provide us with unique, and often fascinating vantage points from which to appreciate their respective political concerns and revolutionary interests. While I expect this critical approach will elucidate Milton and Shelley in their own separate artistic and political spheres, I am especially interested to compare and contrast the poets, to show how the quite different uses made of the grotesque in Prometheus Unbound and Paradise Lost reflect the various ways in which Shelley responds to Milton in his role as a revolutionary forefather.

Traditionally, the resilient modulus values obtained from repeated unconfined or triaxial compression tests are used as the elastic modulus of granular layers in structural analysis of flexible pavements. Sometimes the resilient modulus of granular materials are estimated from known California bearing ratios (CBR) or stabilometer resistance (R) values by simple regression equations. On the other hand, it is well known that stress-strain relation for unbound granular materials is nonlinear and the resilient modulus increases with the increase in stress intensity. There exist several models for stress dependent nonlinear behavior of unbound granular materials. These models are incorporated into elastic layered analysis by applying a method of successive approximations in order to get more realistic pavement responses. Kenlayer is a popular computer program incorporating nonlinear behavior of granular materials in elastic layered system. In this computer program, the resilient modulus of granular materials are varied in vertical direction only, without considering variations in radial direction. In this study, simplest model namely K-Q model for stress dependency of granular layer is applied in structural analysis of flexible pavements. This model is adopted for use in finite element analysis carried by SAP90 software. Analyses are performed over 24 different three-layered pavement structures by changing asphaltic concrete modulus values, granular base thicknesses, base materials and subgrade modulus values. Critical pavement responses namely tensile strains at the bottom of asphaltic surface layers and compressive strains on top of subgrade are obtained for each pavement by linear layered elastic, nonlinear layered elastic and nonlinear finite element solutions. The pavement lives are calculated by using selected performance equations. The results of layered systems and finite element solutions are compared. It is observed that, results obtained from finite element model and linear elastic solutions differ considerably.

Diplomová práce se zabývá problémem přístupu koncového uživatele k odpovědím ověřeným pomocí protokolu DNSSEC. Práce posuzuje možnosti nasazení a nastavování resolveru za účelem zlepšení bezpečnosti pro koncové uživatele. V práci je navrhnuto řešení problému pro operační systém Fedora Workstation. Navrhnuté řešení je realizováno a porovnáno s již existujícím řesením.

According to Swedish guidelines for high speed railways on embankment, the total settlement is limited to 20 mm over a track length of 10 m during the construction service life. The main objective of this thesis was to investigate the deformation in the subgrade (unbound layer) in a slab track, since there are very few studies related to high speed railways on high earth structure, discussing particularly the unbound layer. This thesis examined the unbound layer consisting of granular material by using the discrete element method (DEM) software PFC. There was a focus on the material compaction and deformations due to traffic loading. DEM has the benefit to be able to model deformation with due consideration of processes at microscale level. Two different particle shapes were tested: balls and clumps. The results showed that the settlements were small, possibly associated to the well compacted material and the simplifications in the model, such as the shape of the particles, absence of particle breakage and the applied traffic load. The clump simulations resulted in less settlements and permanent strains compared to the ball simulations. The higher the embankment the more settlements but less strains were produced for all the three simulations. One interesting parameter to study for the balls simulation was the friction between the particles. Increased friction contributed to less settlement. The maximum height of the embankment was limited to around 3,2 m due to time restraints. Simulations for higher embankments are needed to be performed in order to better understand the effect of the embankment height on settlements.

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