The reason analysis of the overburden rock dumps deformation

Due to the deficiency of areas for dump facilities, mining enterprises form dumps of a large height, or locate them in places unfavorable from the stability point of view. In this regard, cases of the dump areas landslides have become more frequent. Herein there are examples of the actual deformations, causes of their occurrence, as well as preventive measures. Experience of the field surveying observations and analysis of the dump landslide causes confirm that accidents could be prevented by timely substantiating of safety criteria for the stress strain status of the dumps and creating methodology for surveying monitoring, depending on a type of the overburden rock.

BIOMECHANICAL ASSESSMENT OFTHESTRESS-STRAIN STATUS OFSPLINTING STRUCTURES AND TEETH PERIODONTIUM IN CASE OF CHRONIC P

The authors have proposed an all-cast pin splint, whose technological feature is the ceramic lining of the over-the-bar part, which acts as a covering aesthetic structure, provides better distribution of the functional load and binds firmly mobile teeth affected by chronic moderate localized periodontitis. The paper offers a view at the outcomes of a comparative analysis of the stress-strain state of periodontal tissues, teeth, and cortical bone in chronic moderate localized periodontitis at the anterior group of teeth in the lower jaw, when they are splinted with a specially designed splint and a conventional metal-ceramic monolithic splint by finite element modeling. The developed 3D mathematical model included, as the initial data, the features of the periodontium, of dental tissue and of cortical bone. There was an examination carried out focusing on the distribution of stresses, which occur when using the designed splint under the impact of multidirectional loads of 130 N, acting strictly down relative to the tooth longitudinal axis (vertically), and a load at an angle of 45°. The proposed method of splinting reduces the maximum stress in the periodontium at a vertical load by 26.9%, while at a side load of 45° it reduced the stress by 34.7%, if compared to a traditional monolithic metal-ceramic splint.

Improvements of Disability Outcomes in CAPABLE Older Adults Differ by Financial Strain Status

The Community Aging in Place–Advancing Better Living for Elders (CAPABLE) program reduces disability in low-income older adults. In this study, we used CAPABLE baseline and 5-month data to examine whether its effects in reducing activities of daily living (ADLs) and instrumental ADLs (IADLs) difficulties differed by participants’ financial strain status. At baseline, participants with financial strain were more likely to report higher scores on depression ( p < .001), have low energy ( p < .001), and usually feel tired ( p = .004) compared with participants without financial strain, but did not differ in ADL/IADL scores. Participants with financial strain benefited from the program in reducing ADL (relative risk [RR]: 0.61, 95% confidence interval [CI]: 0.43, 0.86) and IADL disabilities (RR: 0.69, 95% CI: 0.54, 0.87), compared with those with financial strain receiving attention control. Individuals with financial strain benefited more from a home-based intervention on measures of disability than those without financial strain. Interventions that improve disability may be beneficial for financially strained older adults.

LOAD AND STRAIN STATUS OF CCM BACKUPS AND STRIPE DEFORMATION AT PRODUCTION OF STEEL SHEETS FOR WELDED PIPES. REPORT 2

The main loads acting on the backup-walls of the assembled mold of the combined continuous casting and deformation unit in production of steel sheets for welded pipes are described. The technique for determining the total stresses in backup-walls of the installation of the compression forces and the temperature load is given. The temperature boundary conditions for determining the temperature fields in the backup-walls of the assembled mold of the unit for steel sheets for welded pipes production are depicted. The dependence for determining the heat flux density of the deformation center hot metal influencing working surface of the backup-wall during workpiece drafting is considered, as well as the technique for determining values of effective heat transfer coefficients for backup-walls cooling by water. The procedure for determining temperature fields and thermoelastic stresses on backup-walls of the installation is described using the ANSYS package. The article considers the initial data for determining temperature fields and thermoelastic stresses in backup-walls of the assembled casting mold of the installation. The results of temperature fields and thermoelastic stresses calculation are achieved in five sections of the backup-wall and are provided for the typical lines. The nature of temperature distribution along the backup-wall thickness during cooling by water at idle and at contact with the workpiece during its compression is shown. For the calculated temperature fields, axial and equivalent stresses, that arise in the backup-walls without channels when the workpiece is drafted and cooled with water at idle, are determined. The values and regularities of distribution of axial and equivalent stresses along the thickness of the contact layer and along the height and thickness of the backup-walls during drafting of the workpiece and at idle are presented. The values and regularities of the distribution of total axial stresses along the thickness of the contact layer, the height and thickness of the backup-walls from the drafting forces and the temperature load are given.

Analysis of Internal Cracks in Continuous Casting Slabs with Soft Reduction

The formation of internal cracks in continuous casting slabs is mainly attributed to the strain status and microsegregation near the solidifying front of the slabs. By analyzing the internal cracks of medium carbon microalloy steel, the obtained conclusions are that C, P, S, etc. enrich in dendrites and exist in grain boundaries, but these are just the internal causes, and the root cracking causes the tensile stress of solidification front. When the slab passes through the straightening segments, the liquid core thickness is large, and the liquid steel in the space of columnar crystals is not completely frozen. Therefore, the reduction effect of rollers results in the strain of solidification front exceeding the critical value. However, the corresponding strain in the arc and horizontal segments does not exceed this critical value, so the solidification front in the straightening segments would be much easy to crack. The statistics analysis shows that after soft reduction and straightening process are separately carried out, the occurrence rate of intermediate cracks is reduced by 41.3%.

Reducing dielectric loss in CaCu3Ti4O12 thin films by high-pressure oxygen annealing

High pressure oxygen annealing could reduce the dielectric loss in CCTO films as well as induce obvious difference in strain status.