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encapsuled active principles (eugenol, thymol and vanillin blend) on meat quality of feedlot-finished heifers. Meat Science, 130: 50–57. Destefanis G., Brugiapaglia A., Barge M.T., Dal Molin E. (2008). Relationship between beef consumer tenderness perception and Warner-Bratzler shear force. Meat Sci., 78: 53–156. De Zawadzki A., Arrivetti L.O.R., Vidal M.P., Catai J.R., Nassu R.T., Tullio R.R., Berndt A., Oliveira C.R., Ferreira A.G., Neves-Junior L.F., Colnago L.A., Skibsted L.H., Cardoso D.R. (2017) Mate extract as feed additive for improvement of beef quality. Food Res

Abstract

The chemical composition and culinary meat tenderness belong to the most important characteristics determining meat quality and value. The aim of this work was to compare texture profiles and shear force of pork loin (m. longissimus dorsi) and of pork ham (m. semimembranosus) from fatteners of Polish Landrace (PL), Polish Large White (PLW), Duroc, Pietrain and Puławska pig breeds slaughtered at 60, 90, 120, 150, 180 and 210 d of breeding. Meat was roasted at 180°C to inner temperature of 78°C. The intramuscular fat (IMF) content in loin was growing with fattener age (from 1.17% at 60 d to 1.84% at 180 d of life). Between breeds IMF ranged from 0.82% in PLW to 2.29% in Puławska breed. The shear force for loin muscle ranged from 3.42 kG/cm2 at 60 d to 6.54 kG/cm2 at 210 d of life while for and ham muscle 4.4 kG/cm2 at 60 d to 6.78 kG/cm2 at 210 d of life. The hardness (TPA) ranged from 72.29 N at 90 d of life to 109.46 N at 210 d of life. The shear force of loin and ham meat was increasing with age of fatteners and some texture parameters – hardness and chewiness. Nevertheless it seems that the age of 150 days is the time when meat of fatteners is characterized by the highest technological properties. However, the final decision regarding slaughter age should be made taking into account the technological destination of the carcasses. No significant interactions between the animal breed and their age were found for the parameters analysed.

Abstract

Full flat slabs can be enhanced by using spherical voids to replace the unemployed concrete from the core part of the slab. Therefore we get low self-weighted slabs that can reach a high range of spans, a low material consumption compared to classical solutions used so far. On the other hand, the upsides of these slabs pale against the insecurity in design stage about their punching and shear force behaviour. In this paper it is presented a parametric study about shear force behaviour of flat slabs with spherical voids used in standard condition service. The study was made using the Atena 3D finit element design software, starting form a numerical model gauged on experimental results on real models – scale 1:1. Based on these lab results, the model’s validation was made by overlapping the load – displacement experimental curves on the curves yielded from numerical analyses. The results indicate that under a longitudinal reinforcement rate of lower than 0.50%, flat slabs with spherical voids don’t fail to shear force and over this value the capable shear force decreases in comparison with solid slabs, as the reinforcement rate increases.

Abstract

The bearing capacity of RC overhangs under concentrated loads can be dependent on the width of the slab. The goal of this paper is to investigate the effect of different widths using tests from the literature and non-linear FE-simulations as a reference. Shear force redistributions along the loading process and the shear concrete capacity are analysed. The shear effective width and the influence of an edge beam are also addressed. The results show that the bearing capacity of RC overhangs increase with the width until a transition area is reached and the increase flattens. An increased shear distribution sideways and posterior redistributions under the loading process are enabled. The shear capacity of concrete increases with the width and for loads close to the root an arch effect is observed. The edge beam contributes to a further increase of the ultimate capacity for wide enough overhangs. The effect of the width and the edge beam is not only quantitative but also qualitative since the failure mode and the critical section are influenced. Existing formulation for shear effective widths should be revisited. Experimental tests used for this purpose should consider wide enough specimens to capture the real behaviour of a bridge overhang slab.

Abstract

The contribution presents a set of seismic analyses of multi - storey steel structures with semi-rigid beam column connections acted upon by seismic actions. Semi-rigidity of the structures beam to column connections is conferred by two types of beam to column connections: top and seat and web angle (TSW) and end-plate (EP) joints. Computed numerical results are associated to two classes (static and kinematic) of seismic behaviour parameters expressing the two contradictory effects of semi-rigidity. On one hand, the lateral flexibility induces larger lateral displacements while, on the other hand, it attracts smaller base shear seismic forces. Also, the constitutive relation M − θr induced into semi- rigid beam column connections by seismic actions is presented. The results are presented in their numerical form and in a comparative graphical manner allowing for relevant comments and conclusions

Abstract

Introduction: Glycolic changes which occur post-mortem have an impact on the physical and sensory features of beef, which in turn determine the successive processes and influence such beef quality traits as colour, tenderness, and cooling loss. The aim of this study was evaluation of the post-mortem changes in bovine meat during aging, quantitative analysis of glycogen and lactic acid, as well as examination of their impact on technological and sensory quality of selected muscles from Holstein-Friesian × Limousin breed carcasses.

Material and Methods: The study included three muscles of different metabolic qualities and sarcomere length: m. semitendinosus, m. longissimus dorsi, and m. psoas major, collected from nine bull carcasses aged 24 ±2 months.

Results: Significant correlations were found between the volume of cooling loss on individual days of aging and the pH value of muscle tissue, lactic acid and glycogen content, as well as beef lightness. However, no significant dependency between the volume of glycogen and the intensity of red and yellow colours was detected.

Conclusion: The colorimetric analysis of glycogen and lactic acid can be an effective tool in predicting the quality of beef.

Abstract

At the steel-concrete interface, the horizontal shear forces that are transverse to cross beams occur due to joint action of the steel-concrete composite deck and the truss girders. Numerical analysis showed that values of the forces are big in comparison to the longitudinal shear forces. In both cases extreme force values occur near side edges of a slab. The paper studies possibilities of reduction of these shear forces by structural alterations of the following: rigidity of a concrete slab, arrangement of a wind bracing, arrangement of concrete slab expansion joints. An existing railway truss bridge span has been analysed. Numerical analysis shows that it is possible to reduce the values of shear forces transverse to cross beams. It may reach 20% near the side edges of slabs and 23% in the centre of slab width.

Abstract

A missing piece in the design of bridge substructure is that the equation given in structural mechanics that assesses the axial forces in the piles of a deep foundation does not take into account the effect of lateral forces acting on the pile cap. In practice, pile forces are determined using a FEA software. This method, however, can not be easily incorporated into an automated program that performs local and global optimizations of a structure. One of the reasons is that this method is particularly demanding on the computational resources. Since a bridge can have a number of deep foundations, which must be verified for various combinations of actions, which need to be optimized, recalculated in various scenarios and then the entire process reiterated for all structural solutions, computational cost can become prohibitive. Another reason is that due to the lack of a relation between all the parameters and dimensions that influence the behaviour of a deep foundation, their optimization is difficult.

For this purpose, a parametric study has been carried out to investigate what parameters influence the relation between the lateral forces applied to the foundation and the axial forces that develop in the piles, and ultimately propose an equation that takes into account the lateral forces. The study is carried out using experimental data obtained on models using the finite element analysis method using SAP 2000 (v.15) software.

Abstract

Experience of designing buildings with structural masonry walls and masonry non-structural elements using Codes CR 6-2006 [15a] and P 100-1/2006 [16a], that were developed based on design principles and rules of Eurocodes adopted in Romania SR EN 1996-1-1[13] and SR EN 1998-1[14], revealed the need of some additions and corrections of texts.

These interventions made by developing Codes CR 6 -2013[15] and P 100-1/2013[16], which we can characterize synthetically as follows:

  • - Are aligned with the Structural Eurocodes principles but correcting some identified deficiencies.
  • - Resume some previous provisions of national regulations that lack in Eurocodes
  • - Introduce the results of recent theoretical and experimental research
  • - Provide practical application rules, simple and explicit, accompanied by “Commentary” and “Design examples”

The communication exposes and justifies synthetically the following new approaches introduced in the 2013 editions of the two regulations:

  • Modification of the methodology for the partial safety factors (γM) and for establishing the minimum necessary strength values of masonry.
  • Additions and explanations of the design rules for unreinforced and confined masonry subjected to combined axial compression and flexure and to shear loading.

(in Polish). Rocz. Nauk. Zoot. Supl., 11: 67-86. Borzuta K., Strzelecki J. (2001). Capabilities of good quality culinary lamb production (in Polish). Rocz. Nauk. Zoot. Supl., 11: 13-21. Cloete J.J.E., Hoffman L.C., Cloete S.W.P. (2012). Acomparison between slaughter traits and meat quality of various sheep breeds: wool, dual-purpose and mutton. Meat Sci., 91: 318-324. Destefanis G., Brugiapaglia A., Barge M.T., Dal Molin E. (2008). Relationship between beef consumer tenderness perception and Warner-Bratzler shear force. Meat Sci., 78: 153-156. Devine C.E., Graafhuis