Safety and Stability of Structures with Semi-Rigid Connections of Members in Nodes

The structural design of a system in which connections of members are absolutely rigid or perfectly pinned has been thoroughly worked out in the existing literature. In real structures in general, and particularly in the precast ones, connection in joints may be partially rigid, which can have a significant impact on the change of stresses and strains in the structure, i.e. on the stability and security of the structure.Testing of engineering structures, i.e. conditions that must be met so that they remain in stable equilibrium position is of special importance. To determine the limit state of stability in use are experimental and analytical methods based on static, dynamic and energetic principles.This article presents the methods used to ensure technical safety and security, as well as additional safety conditioned by public and social reasons. The functional damage and fatigue are discussed, as well as the concept of the projected lifespan of the structure. Increased strength provides a higher degree of security, although many factors are variable

Comparative Analysis of Limit Bearing Capacity of a Continuous Beam Depending on the Character of the Load

Determination of the bearing capacity of a structure, as well as the assessment related tothe structure failure is very valuable, not only as a simple control of beam bearing capacity,but also as a significant basis and factor in designing of structures. When the structure isexposed to the action of a proportionally increasing load, by applying the limit analysis it ispossible to determine the limit failure load which is one of the bearing capacity indicators. Inthe case when beam systems are exposed to repeated load, the limit theorems do not yield the adequate solutions, thus the adaptation theorems which made safe limit load determination possible were developed simultaneously. Applying the limit and shakedown analysis, the analysis of bearing capacity of a continuous beam with two spans was conducted in the paper.Also displayed is the difference between the values of failure forces depending on the character of load and the beam span value in order to assess justification for application of the shakedown method in the analysis of the limit bearing capacity of the beams

Static Design of Systems with Semi-Rigid Connections Based on Experimental Investigation of the Full Scale Structure

The paper presents the basic theory and corresponding equations for calculation of the static influences of the structures with semi-rigid connections in joints. The static design of system in which connections of members are absolutely rigid or perfectly pinned has been thoroughly worked out in the existing literature. In real structures in general, and particularly in the precast ones, connection in joints may be partially rigid, which can have a significant impact on the change of stresses and strains in the structure. In the world there are several procedures, with different approaches, to the structural design with semi-rigid connections, however, it is proved that they all lead to the same results. All of these approaches in addition to theoretical deal with experimental analysis of results. According to the approach that will be presented in this paper, typical prefabricated structures "Minoma" 1, "Minoma" 2, and "Minoma" 3 with span of 12m, 20m and 27m respectively, and the height of the column up to 9m, have been experimentally analyzed. A numerical example will be given and discussed, where bending moments due to a given load, as well as due to input force in the tensioner, have been calculated for defined levels of rigidity of connection using the deformation method. The obtained superimposed bending moment diagram will be analyzed too

SEIZMIČKA ANALIZA RAMOVA SA POLUKRUTIM VEZAMA U SKLADU SA EC8

Up to date research has pointed out that most of the structural connections of reinforced concrete (RC) frames, particularly precast ones, behave as semi-rigid. Therefore, it is of great importance to develop an analysis method which takes into account the connection rigidity. For that purpose matrix formulation of the deformation method is used in this paper, and the effect of rigidity of connections on the structure response is included by stiffness matrix for semi-rigidly connected member. The elements of this matrix are functions of the fixity factors at the ends of members. The proposed method is applied in seismic analysis of the precast RC frame structure of the existing industrial hall according to Eurocode 8 (EC8).Dosadašnja istraživanja su pokazala da se većina konstruktivnih veza armiranobetonskih (AB) ramova, posebno montažnih, ponaša kao delimično krute. Zbog toga je od velike važnosti razviti metod analize koji uzima u obzir krutost veze. U ovom radu je za to korišćena matrična formulacija metode deformacije, a uticaj krutosti veza na odziv konstrukcije obuhvaćen je matricom krutosti za delimično kruto vezani štap. Elementi ove matrice su funkcije stepena uklještenja na krajevima štapova. Predložena metoda je primenjena u seizmičkoj analizi prefabrikovane AB ramovske konstrukcije postojeće industrijske hale u skladu sa Evrokodom 8 (EC8)

Predictors of unmet health care needs in Serbia; Analysis based on EU-SILC data.

Unmet health care needs have been designated as an indicator of equality in access to health care, which provides insight into specific barriers faced by respondents when they need medical services. The purpose of this research was to analyze demographic, socioeconomic, regional characteristics and perception of the health status; and identify predictors of unmet health care needs and consequently determine the size of inequalities in the availability, accessibility and acceptability of health care. The cross-sectional study obtained data from the Survey on Income and Living Conditions in the Republic of Serbia in 2014, based on a sample of 20,069 respondents over 16 years. Data was collected by using a household questionnaire and a questionnaire for individuals. Multivariate logistic regressions were applied. Almost every seventh citizen (14.9%) reported unmet health care needs. Predictors of unmet needs, for overall reasons, which increase the likelihood of their emergence included: self-perceived health status as very bad (OR = 6.37), divorced or widower/widow (OR = 1.31), living in the Sumadija region or Western Serbia (OR = 1.54) and belonging to the age group of 27 to 44 (OR = 1.55) or 45 to 64 years (OR = 1.52). The probability for those least reporting unmet health care needs included female patients (OR = 0.81), those with higher education (OR = 0.77), those who belong to the richest quintile (OR = 0.46) and who are unemployed (OR = 0.64). Reasons for unmet needs that indicate the responsibility of the health system amounted to 58.2% and reasons which represent preferences of the respondents amounted to 41.7%. The most frequent reason for unmet needs was financial (36.6%), and the wish to wait and see if the problem got better on its own (18.3%). Health policy should adopt a multidimensional approach and develop incentives for the appropriate use of health services and should eliminate barriers which restrict the accessibility and availability

The main reason why respondent did not visit a doctor, by regions.

<p>The main reason why respondent did not visit a doctor, by regions.</p