Behaviour of sandy soil subjected to dynamic loading

This thesis presents the kinematics occurring during lab-based dynamic compaction tests using high speed photography and image correlation techniques. High speed photography and X-ray microtomography have been used to analyse the behaviour of sandy soil subjected to dynamic impact. In particular, the densification mechanism of granular soils due to dynamic compaction is the main theme of the thesis. High speed photography and digital image correlation (DIC) techniques have enabled the deformation patterns, soil strains and strain localisations to be observed. Image correlation and X-ray scans revealed the formation, rate and growth of narrow tabular bands of intense deformation and significant volumetric change and provided answers towards a better understanding of the densification mechanism in dry granular soils due to dynamic compaction. As a quantitative tool, high speed photography has allowed the propagation of localised deformation and strain fields to be identified and has suggested that compaction shock bands control the kinematics of dynamic compaction. The displacement and strain results from high speed photography showed that soil deformation in the dynamic tests was dominated by a general bearing capacity mechanism similar to that widely stated in classic soil mechanics texts. Comparative static loading tests have been conducted to enable the dynamic effects to be clearly distinguished. This has enabled the densification process taking place below the soil surface to be investigated and identified. Simulations of the physical models were carried out using LS-DYNA finite element formulations for comparison and verification purposes. The FE simulations verified the general characteristics from the photography findings. However, simulation results were unable to predict the exact details of the strain localisation due to surface impacts during physical model tests

Clinical significance of long-term psychoanalytic treatment

Contains fulltext : 90480.pdf (publisher's version ) (Open Access)The present study evaluated the clinical significance of long-term psychoanalytic treatment in four groups of about 60 patients in different phases of treatment (before, during, after, follow-up) with normative comparisons on four symptom questionnaires (SCL-90, BDI-II, STAI, IIP-64) and two personality assessment instruments (MMPI-2, Rorschach-CS). In each group, the proportion of patients with clinically elevated scores was calculated by comparing their scores with clinical and nonclinical reference groups for each instrument. The authors also calculated a combined percentage of clinically elevated scores based on the six instruments as a conservative estimate of improvement to nonclinical levels after long-term psychoanalytic treatment. Compared to pretreatment levels, the authors found a significant decrease in the Percentage of clinical cases after treatment. For the personality assessment, these results became even more evident at follow-up. It appears that long-term psychoanalytic treatment was clinically significant for patients with chronic mental disorders. In the discussion, the authors point out that the, evaluation of clinical significance at group level should be followed by an examination of individual changes over a longer period of time.27 p

Identifying clinical cases among patients assigned to psychoanalytic treatment

Contains fulltext : 73282.pdf (publisher's version ) (Open Access)The present study compared 89 patients assigned to long-term psychoanalytic psychotherapy or psychoanalysis in the Netherlands with psychiatric and nonclinical norm groups with regard to symptoms and personality pathology as assessed with six instruments. Patients filled in four self-report questionnaires (Symptom Checklist-90-Revised [SCL-90-R], Beck Depression Inventory-II [BDI-II], State-Trait Anxiety Inventory [STAI]) and underwent a personality assessment (Minnesota Multiphasic Personality Inventory-2 [MMPI-2], Rorschach-CS). The authors used statistically defined cutoff values for each measure. For each instrument separately, about 50% of the patients reported clinical levels of psychopathology, some patients being more depressed and others reporting other symptoms. By combining the test scores of the different instruments, the authors found that 91% of the patients were identified as clinical cases. Compared to psychiatric norm groups, these patients appeared to report lower levels of symptom distress, but similar levels of personality pathology. The next step will be to investigate the level of improvement after long-term psychoanalytic treatment. (Bulletin of the Menninger Clinic 72[4], 163-178)16 p

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