Structural integrity of a wind loaded cylindrical steel shell structure

The structural integrity and life assessment can be considered as a mandatory request in the civil engineering designing and manufacturing process. The paper is presenting the procedure for determination of crack acceptability based on fracture toughness with failure assessment methods (FAD-1 and FAD-2) which is applied to a cylindrical steel shell structure with welded joints which is having the wind as a main load. The assessment is using BS7910/2013. Thus were assessed common types of flaws met at steel shell cylindrical structure elements using failure assessment diagrams - level 1 - FAD-1. The results are presenting the acceptability level for each type of flaw with comparative graphs, determining also the critical dimension of the flaw. For each flaw was calculated the failure assessment diagram (FAD-2). Different comparisons between group of flaws were done, revealing the critical crack like flaw. Also the critical value of flaw dimensions were calculated for each flaw type. The methodology establishes clear rules for assessment of structural elements with cracks, determining the initial flaws, assessed flaws and critical values of the cracks. Based on the detailed procedures described in the paper, on conclusions to the assessment done on each type of flaw, the assessment methods can be applied very easy in current design practice with different material characteristic

New island of cluster emitters

A new region of proton-rich parent nuclei decaying by spontaneous cluster emission with a measurable branching ratio relative to alpha decay is predicted within the analytical superasymmetric fission model. After a brief presentation of the model and of the seven mass tables used to calculate the released energy, the obtained results are discussed. Measurable half-lives and branching ratios are estimated for 12C, 16O, 28Si, and other cluster radioactivities of some nuclides having proton and neutron numbers in the range Z=56–64 and N=58–72. Such nuclei far from stability could be produced in reactions induced by radioactive beams

Two-dimensional nuclear inertia : analytical relationships

The components of the nuclear inertia tensor, functions of the separation distance R and of the radius of the light fragment R2, BRR(R,R2), BRR2(R,R2), and BR2R2(R,R2) are calculated within the Werner-Wheeler approximation, by using the parametrization of two intersected symmetric or asymmetric spheres. Analytical relationships are derived. When projected to a path R2=R2(R), the reduced mass is obtained at the touching point. The two one-dimensional parametrizations with R2=const, and the volume V2=const previously studied, are found to be particular cases of the present more general approach. Illustrations for the cold fission, cluster radioactivity, and α decay of 252Cf are given

Refurbishment of Existing Steel Structures – an Actual Problem

Many steel structures erected at the end of the XIX and begin ofthe XX-centuries still are in function. Some of these structures,particularly bridges, have already achieved an age of ninety,hundred or even more years and are still in operation afterdamages, several phases of repair and strengthening. Replacementwith new structures raises financial, technical and politicalproblems. The budget of the administration gets smaller.Information about the safety of the structure, the remaining life,the costs for maintenance etc. are important. Nobody will takethe responsibility for failure of a structure as a result of budgetrestriction. The aim of the paper is to emphasize the importanceof refurbishment of existing steel structures, part of sustainabledevelopment

Univalence criteria for integral operators

The aim of this paper is to obtain new univalence criteria for integral operators which were introduced by N. N. Pascu and S. Moldoveanu. The improvement consists in the fact that the new hypothesis are more simple, that is they do not contain |z|. On this reason these can be easily applicated

Potential energy surfaces for cluster emitting nuclei

Potential energy surfaces are calculated by using the most advanced asymmetric two-center shell model allowing to obtain shell and pairing corrections which are added to the Yukawa-plus-exponential model deformation energy. Shell effects are of crucial importance for experimental observation of spontaneous disintegration by heavy ion emission. Results for 222Ra, 232U, 236Pu and 242Cm illustrate the main ideas and show for the first time for a cluster emitter a potential barrier obtained by using the macroscopic-microscopic method.Comment: 10 pages, 21 figures, revtex

Structural integrity of butt welded connection after fire exposure

The paper presents a study for fire behavior of the butt-welded joints subjected to low cycle fatigue loading, taken into account the post fire conditions and the possibility of welding strengthening. The need of in service life of a steel structure after being exposed to fire raises the problem of strengthening or replacement of some structural elements. There is presented a case study a building structural element subjected to dynamic loading after fire exposure [1]. For the in case study, post fire investigations revealed several welding flaws including crack type flaws. An assessment was needed in order to determine the structural integrity and life assessment of some structural elements. From the fracture mechanics point of view, a Failure Assessment Diagrams level 2 - FAD 2 procedure was applied in order to determine the in service safety of the structure. Several flaws types were assessed and conclusions were taken. The results can be used for damage assessment and strengthening technique of post fire steel structures

Research on the Sensorial Quality and Economic Efficiency in Obtaining of a certain Raw Meat Product - Mici Paste

Research aimed the sensorial quality connected with the economic efficiency to obtain a certain raw meat product (mici paste) in 4 experimental variants: 1 and 3 variants, with animal raw materials (meat + bacon) and mix of natural spices - fine grinding variant (1) and coarse grinding variant (3) - chopping at the volf through the sieve of 3-4 mm; 2 and 4 variants, with animal raw materials (meat + bacon) + vegetable protein supplements (textured soy protein) + binder (protein + fiber) + additive mix - fine grinding variant (2) and coarse grinding variant (4) - chopping at the volf through the sieve of 3 - 4 mm. In this respect organoleptic analyzes were performed on appearance (exterior and section), color, smell, texture and taste of the finished product (after roasting), the results highlighting that, in terms of organoleptic, sample 1 obtained the highest score (on a scale of 1-poor to 5-very good quality) (average 21.83), followed by sample 3 (average 19.22), the very small difference in the case of sample 2 (average 19.19) and finally, sample 4 (average 18.75). It was noted that sample 1 obtained the highest score (average) of all analyzed organoleptic indicators: appearance (4.33), color (4.39), smell (4.67), texture (4.33) and taste (4.11) being favorite by all volunteer subjects who participated at the analysis. The same thing was found in sensory analysis of mici paste in fresh/chilled condition: 65% of subjects preferred variant 1 followed by variant 3 (19.2%), variant 2 (11.5%) and finally, variant 4 (3.8%). In terms of economic the highest efficiency was found in 2 (specific consumption 0.73) and 4 (specific consumption 0.77) variants compared to 1 (specific consumption 0.80) and 3 (specific consumption 0.82) variants, which translates into a reduction in the cost of products manufactured in the variants 2 and 4 (with protein supplements and additive mix) by about 25-20% (with importance for the manufacturer). Also, thermal processing (roasting) revealed the highest weight loss (drying) in 3 (18.75%) and 1 (12.50%) variants compared to 4 (12.33%) and 2 (10%) variants in which case the vegetable protein supplements contributed to increased water retention capacity, and the processing way of the raw materials - their mechanical grinding (in this case) was another important factor that influenced the level of these technological losses that have a negative impact on the consumer. In conclusion, the 2 and 4 variants reveals higher functional, technical and economic advantages compared with 1 and 3 variants and also the customer satisfaction. Therefore, in order to obtain qualitative and economic performance, in product processing must take into account both technical and functional considerations, nutrition and the economic ones