Spelling suggestions: "subject:"tiers"" "subject:"piers""
61 |
Experimental Investigation Of Local Scour Around Inclined Dual Bridge PiersCesme, Murat 01 September 2005 (has links) (PDF)
For a bridge engineer, it is very important to estimate the maximum scour depth around the piers as accurately as possible, in order to design the footing safely. Many experimental studies have been performed by several investigators until now, in order to obtain information about scouring mechanism. The aim of this experimental study is to examine the effect of inclination of the dual bridge piers on scour depth. The experiments have been conducted with dual pier models under clear-water conditions, for various uniform flow depths. Scour depths had been measured at four different points around the piers / namely upstream and downstream faces of both piers. Dimensional and non-dimensional scour curves have been developed and presented to show the temporal variation of scour depth. The depths of local scour around inclined piers have been observed to be smaller than the scour depths around vertical piers.
|
62 |
The Significance of Dmitri Shostakovich's Piano Sonata Op.12Kan, Ling-Yu 05 1900 (has links)
The aspiration of this dissertation is to bring forth the significance of Shostakovich's Piano Sonata Op.12. This sonata is a hybrid of the German musical tradition, Russian Modernism, and Liszt's thematic transformation technique. It demonstrates Shostakovich's highly intellectual compositional skills influenced by the education that he received at St. Petersburg Conservatory as well as the exposure to modern music in the 1920s. This dissertation discusses composition techniques, such as the harmonic piers adapted from Alexander Scriabin, neighboring-tone technique, which involves the application of semitone cell throughout the piece, as well as the technique of thematic transformation borrowed from Liszt. These all come together by Shostakovich's design in the most controversial sonata form. The Piano Sonata Op.12 also sheds light on Shostakovich's early compositional style and proves its contribution to the evolution of sonata genre in the twentieth-century.
|
63 |
The Evaluation on the Effectiveness of Shields for Bridge Pier ProtectionNepal, Prateek January 2020 (has links)
No description available.
|
64 |
Environmentally Friendly and Sustainable Stream Stability in the Vicinity of BridgesCope, Evan David 12 March 2014 (has links) (PDF)
This report was sponsored by the Utah Department of Transportation (UDOT) to determine if stream restoration structures could be used as scour countermeasures near state highways and bridges. Scour countermeasures that are effective in preventing erosion exist but that are not so friendly for aquatic organisms. UDOT is interested in finding a countermeasure that is both effective in preventing erosion while not harming aquatic organisms. Stream restoration structures are friendly for aquatic organisms but are prone to failure when flows exceed the design levels. David Rosgen has developed restoration structures that are friendly for aquatic organisms and that have provided streambank protection. These structures are the J-Hook vane, Cross-Vane and W-Weir. Based research done in this report, Cross-Vanes and W-Weirs are best suited to protect bridges because they will protect both sides of a stream bank. For these restoration structures to be reliable at higher flows and shear stresses experienced at bridges, they must follow the design criteria specified in this report. One of the most important design requirements is that the structures designed by David Rosgen have an attached floodplain where the structure meets the streambank. The floodplain disperses the energy of the flow, reducing shear stress. In the vicinity of some bridges, a floodplain cannot be implemented. In such cases, culverts can be installed at the floodplain level, that pass under the bridge to help reduce shear stresses, mimicking a floodplain. Cross-Vanes and W-Weirs can be used to protect bridges and other infrastructure. Based on modeling and comparing restoration structures to a labyrinth weir, they still have an impact on higher flows. At higher than design flows, such as experienced at bridges, the structures help to reduce shear stresses. To further investigate their use as a scour countermeasure near bridges, it is recommended that a structure be installed near a bridge following this report's design criteria. This will be determined depending on available funding.
|
65 |
Long-Term Behaviour of Model Piers in Weak RockChae, Kyu-Jong 05 1900 (has links)
<p>The research contained in this thesis is concerned with longterm behaviour of drilled piers socketed in weak rock. The experimental work involved testing of two steel and seven concrete model piers. The 25.4 mm (1.0 in) diameter steel piers had relatively smooth socket walls (RF = 0.033) and were socketed into pseudo-rock material. The concrete piers were 76.2 mm (3.0 in) in diameter and were socketed into weak rock (Queenston Shale). The concrete piers were of two types: conventional socketed piers with relatively smooth socket walls (RF = 0.025) and grooved piers with relatively rough socket walls (RF = 0.081 and 0.303).</p> <p>The piers were tested under two condition of load support, shaft resistance only and combined shaft resistance and end-bearing support conditions.</p> <p>In case of steel piers, electrical resistance strain gauges were mounted on the pier shaft to measure the load distribution along the shaft of the piers. For concrete piers under combined shaft resistance and end-bearing support conditions, flat jack load cells with Marsh and Budenberg pressure gauges and/or electrical pressure transducers were used to measure the load transfer at the base.</p> <p>All model piers were axially loaded in the laboratory using load frames designed and fabricated for this purpose. The axial loads were iii applied by the air cylinders and held constant throughout the period of testing using a regulated air pressure supply.</p> <p>The test results confirmed that performance of socketed piers can be significantly improved by increasing the roughness of the pier-rock interface. Both the primary creep rate and the load transfer with time were larger for piers with small shaft roughness.</p> <p>A second stage of creep having a much lower creep rate was observed for all model tests. The time to the end of primary creep was found to depend on the roughness of the socket wall. The primary and secondary creep rate appeared to be dependent on the stress level, shaft roughness, compressive strength of weak rock and support conditions.</p> <p>The results of the model tests are compared with available test data and with values predicted using methods based on viscoelastic analysis. This method of analysis for piles in clay soils has been modified for application to socket piers in weak rock. It is suggested that the modifications can be used to estimate the long-term settlement of socket piers in weak rock</p> / Master of Engineering (ME)
|
66 |
A cognitive-behavioural therapeutic approach to anger management in adolescent malesMahoney, Janine, N/A January 1993 (has links)
The present investigation evaluated the efficacy of a Cognitive-Behavioural
Therapeutic Approach for the anger management of three adolescent males. The study
is noteworthy because it utilised essential features of Beck's Cognitive Therapy in the
cognitive restructuring phase of treatment. Previous studies have commonly employed
Rational Emotive Therapy's disputation of irrational beliefs for this phase. For this
reason it is considered to be an original contribution to the literature.
A multiple (three) single-case study research design was employed. The three
adolescents, aged 13 to 17 years, attended seven to nine one-hour counselling
sessions over a two to three month period. Pre-, post-treatment and long-term followup
psychometric measures of aggression and anecdotal reports of anger-control were
obtained from parents and teachers. Self-reports in the affective and cognitive domain,
progress in therapy, psychometric measures (aggressive behaviour subscale of the
Child Behaviour Checklist, Adapted Novaco Anger Inventory and Piers-Harris
Children's Self-Concept Scale) and continuous (including pre-, post-treatment and
long-term follow-up) assessments of the frequency of angry outbursts were obtained.
Counsellor assessments of cognitive homework and behaviour in therapy were also
made.
Results reveal marked reductions in the average daily frequencies of angry
outbursts in all cases by post-treatment and treatment effects were maintained
throughout the three-month follow-up period.
It was concluded that the cognitive-behavioural therapeutic approach warrants
further investigation as it is proposed that it is a comprehensive and efficacious
treatment for male adolescent anger problems.
|
67 |
The contribution of temperament to children's happinessKlassen, Andrea Nicole 11 1900 (has links)
The relation between temperament and happiness in children aged 8-12 was
examined. Participants included 311 students in Grades 4-6 and their parents, recruited from
public and private schools in the Central Okanagan. Parents rated their children’s
temperament using the Emotionality, Activity, and Sociability (EAS) Temperament Survey
(Buss & Plomin, 1984) and rated their children’s happiness using a single-item measure.
Children rated their own temperament using the EAS Temperament Survey and the Piers-
Harris Self Concept Scale for Children, Second Edition (Piers-Harris 2) (Piers & Herzberg,
2002). Children also rated their own happiness using a single-item measure, the Oxford
Happiness Scale, Short Form (Hills & Arygle, 2002), and the Subjective Happiness Scale
(Lyubomirsky & Lepper, 1999). Confirmatory factor analyses established that parent and
child ratings on the EAS Temperament Survey conformed to the four-factor structure
proposed by Buss and Plomin (1984). Multiple regression analyses revealed that
temperament accounted for between 9-29% of the variance in children’s happiness
depending on the rater (i.e., parents vs. children) and the measure of happiness. Individual
temperament variables that predicted a unique amount of the variance of children’s happiness
over and above the combined effect of all temperament variables varied with the rater of
children’s temperament (i.e., parents vs. children) and with the measure of happiness.
Children who were more social, less shy, less emotional, and more free from anxiety rated
themselves, and were rated by others, as happier. Children who scored higher on the activity
temperament rated themselves, and were rated by others, as happier. The results of the
current study parallel results of research investigating the relation between happiness and
personality in adults. It establishes a strong relation between temperament and happiness, and
iii
supports the use of self-reports with children. Implications and suggestions for future
research are discussed.
|
68 |
A Simplified Model for Lateral Response of Caisson FoundationsVarun 20 November 2006 (has links)
Caisson or pier foundations are encountered as part of the foundation system of tall structures such as bridges, transmission towers, heliostats, etc, and correspond to rigid blocks of length-to-diameter (D/B) ratio on the order of D/B = 2-6. As a result of their geometry and stiffness characteristics, the mechanisms of load transfer from the superstructure to the surrounding soil and their kinematic response to seismic wave propagation are governed by a complex stress distribution at the pier-soil interface, which cannot be adequately represented by means of simplified Winkler models for shallow foundations or flexible piles. Continuum model solutions, such as 3D finite elements (FE) cannot be employed frequently in practice for the design of non-critical facilities due to the cost and effort associated with these analyses. The objective of this work is to develop a Winkler-type model for the analysis of transversely-loaded caissons, which approximately accounts for all the main soil resistance mechanisms mobilized, while retaining the advantages of simplified methodologies for design at intermediate levels of target accuracy. Investigation of the governing load-transfer mechanisms and development of complex spring functions is formulated on the basis of 3D FE simulations. Initially, the soil-structure stiffness matrix is computed by subjecting the pier to transverse static and dynamic loading at the top, and numerically estimating the response. Complex frequency-dependent functions are next developed for the spring constants by equating the stiffness matrix terms to the analytical expressions developed for the four-spring model. Sensitivity analyses are conducted for optimization of the truncated numerical domain size, finite element size and far-field dynamic boundary conditions to avoid spurious wave reflections. Simulations are next conducted to evaluate the transient response of the foundation subjected to vertically propagating shear waves, and results are compared to the response predicted by means of the 4-spring model. Finally, the applicability of the method is assessed for soil profiles with depth-varying properties. While the methodology developed is applicable for linear elastic media with no material damping, the expressions of complex spring functions may be extended to include hysteretic damping, nonlinear soil behavior and soil-foundation interface separation, as shown in the conclusions.
|
69 |
Stress relaxation of stainless steel rods for bridge pier cap shear strengtheningKrapf, Carlyn Nicole 07 April 2010 (has links)
This thesis examines the stress relaxation phenomenon that may occur in stainless steel rods that are used as part of an all-stainless steel externally post-tensioned rod system for strengthening reinforced concrete pier caps in shear. An overview of the stress relaxation phenomenon and its modeling is presented. Previous work on stress relaxation of stainless steel is reviewed and used to select an appropriate stress relaxation model to analyze the stress relaxation data obtained from experiments performed during this research. An experimental program utilizing six specimens of Type 304/304L stainless steel stainless steel rods similar to those likely to be candidates for pier cap rehabilitation is presented, and the data are analyzed using the model identified from the review. This model reasonably captures the behavior of the resulting stress relaxation with time, and calculates stress values that are fairly close to those obtained experimentally. Using this model to predict long-term stress losses in a service environment, guidelines for design and installation of the post-tensioned stainless steel rods are proposed.
|
70 |
The contribution of temperament to children's happinessKlassen, Andrea Nicole 11 1900 (has links)
The relation between temperament and happiness in children aged 8-12 was
examined. Participants included 311 students in Grades 4-6 and their parents, recruited from
public and private schools in the Central Okanagan. Parents rated their children’s
temperament using the Emotionality, Activity, and Sociability (EAS) Temperament Survey
(Buss & Plomin, 1984) and rated their children’s happiness using a single-item measure.
Children rated their own temperament using the EAS Temperament Survey and the Piers-
Harris Self Concept Scale for Children, Second Edition (Piers-Harris 2) (Piers & Herzberg,
2002). Children also rated their own happiness using a single-item measure, the Oxford
Happiness Scale, Short Form (Hills & Arygle, 2002), and the Subjective Happiness Scale
(Lyubomirsky & Lepper, 1999). Confirmatory factor analyses established that parent and
child ratings on the EAS Temperament Survey conformed to the four-factor structure
proposed by Buss and Plomin (1984). Multiple regression analyses revealed that
temperament accounted for between 9-29% of the variance in children’s happiness
depending on the rater (i.e., parents vs. children) and the measure of happiness. Individual
temperament variables that predicted a unique amount of the variance of children’s happiness
over and above the combined effect of all temperament variables varied with the rater of
children’s temperament (i.e., parents vs. children) and with the measure of happiness.
Children who were more social, less shy, less emotional, and more free from anxiety rated
themselves, and were rated by others, as happier. Children who scored higher on the activity
temperament rated themselves, and were rated by others, as happier. The results of the
current study parallel results of research investigating the relation between happiness and
personality in adults. It establishes a strong relation between temperament and happiness, and
iii
supports the use of self-reports with children. Implications and suggestions for future
research are discussed.
|
Page generated in 0.0354 seconds