Interface condition influence on prediction of flexible pavement life

The effects of interface condition on the life of flexible pavements have been determined. The methodology consists of implementing a previously derived interface constitutive model into the Kenlayer programme to compute the stresses and strains in typical flexible road structures. The shell transfer functions for fatigue cracking and terminal serviceability were used to estimate the pavement life. The behaviour of in‐service pavements indicates that the condition of the bonding between pavement layers plays an important role in the road structures performance. Premature failure of road sections due to layer separation, leading to redistribution of stresses and strains in the pavement structure, is often encountered, especially in areas where the vehicles are more likely to apply horizontal forces. In computing the critical stresses and strains, most of the mechanistic design procedures of flexible pavement structures consider that pavement layers are completely bonded or completely unbounded. Susieties būklės įtaka nestandžiųjų dangų tarnavimo trukmei numatyti Santrauka Straipsnyje nustatyta susieties būklės įtaka nestandžiųjų kelio dangų tarnavimo trukmei numatyti. Pagal taikytą metodiką anksčiau sukurtas sudėtinis susieties modelis buvo įdiegtas į Kenlayer programą tam, kad būtų galima apskaičiuoti įtempius ir deformacijas tipinėse nestandžiųjų kelio dangų konstrukcijose. Dangos naudojimo trukmė apskaičiuota pasitelkiant sluoksnių perkėlimo funkcijas nuovargio plyšiams ir ribinio tinkamumo eksploatacijai. Esamų dangų elgsena rodo, kad dangos sluoksnių tarpusavio surišimo būklė yra labai svarbi kelio dangos konstrukcijos kokybei. Ankstyvas dangos ruožų irimas dėl sluoksnių atsiskyrimo, dėl kurio dangos konstrukcijos įtempiai ir deformacijos persiskirsto, yra gana dažnas, ypač tose vietose, kur transporto priemonės sukelia horizontaliąsias jėgas. Apskaičiuojant kritinius įtempius ir deformacijas, daugumai mechaninio nestandžiųjų dangų konstrukcijų projektavimo metodikų imama, kad dangos sluoksniai yra visiškai surišti arba visiškai nesurišti. Reikšminiai žodžiai: būklė, tiesinis tamprumo modelis, pagruntavimas, nestandžioji danga, Kenlayer programa, sluoksnių perkėlimo funkcijos, nuovargis, vėžių susidarymas. First Published Online: 14 Oct 201

Resilient behaviour of hot mixed and crack sealed asphalt concrete under repeated loading

Bituminous mixes are becoming increasingly important in the road industry. The road engineers identify rutting as a major source of distress in Hot Mix Asphalt (HMA) pavements. The Asphalt Mix Design Marshal method adequately addresses the aggregate and asphalt binder properties that contribute to permanent deformation. However, there is no laboratory test currently at hand to quickly predict permanent deformation susceptibility of HMA. The main purpose of this paper is to provide practical information of laboratory samples for practitioners and mix designers. Thus, relevant test procedures and results of tests conducted are reported in this paper. Two resilient behaviours of cracked sealed asphalt concrete were studied by varying temperature and time of loading to understand the crack sealed pavement behaviour under Iran conditions. Karšto ir supleišėjusio asfaltbetonio tamprumas veikiant kartotinei apkrovai Santrauka Bitumo mišiniai tampa vis svarbesni kelių statyboje. Kelių tiesėjai nustatė, jog didžiausia problema yra provėžos karštoje kelio dangoje. Asfalto mišinio užpildų ir rišamosios medžiagos savybių įtaką ilgalaikėms deformacijoms tiksliai vertina Maršalo metodas, tačiau šiuo metu nėra jokio laboratorinio testo, kuris operatyviai nustatytų ilgalaikes karšto betono mišinio deformacines savybes. Pagrindinis šio straipsnio tikslas – suteikti informaciją apie laboratorinius bandinius mišinių gamintojams ir kelininkams. Taigi čia aprašyti atlikti testai ir gauti rezultatai. Bitumo kiekio mišinyje ir temperatūros įtakos ilgalaikėms asfalto dangos deformacijoms tirti panaudota laboratorinė įranga. Bandant suvokti supleišėjusios dangos elgseną Irano sąlygomis, nagrinėtos dvi supleišėjusio asfaltbetonio tamprumo charakteristikos, keičiant temperatūrą ir apkrovimo trukmę. First Published Online: 21 Oct 2010 Reikšminiai žodžiai: ilgalaikė deformacija, Maršalo metodas, karšto asfalto mišinys, provėžos, įtempis, pleišėjimas

Mapping 123 million neonatal, infant and child deaths between 2000 and 2017

Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations

Studying the effects of using total quality management (tqm) in construction sites (case study steel structure building)

Total quality management (TQM) is one of the most useful and effective methods used in management systems that effectively include the topics of quality. In this study, the effects of use of TQM is examined in construction workshops and in a case study manner on a set of metal buildings and all of its steps from the beginning to the accomplishment of the building is explained. In this study, for identifying the weaknesses and problems of management approaches derived from lack of proper management in the metal buildings, manner of implementation of TQM in other countries, are examined. Therefore, by identifying the weaknesses of management of previous examples, one can take a significant step for improving and enhancing the management system and quality of construction of the country

The Scales of Asian Football Confederation and the Success of Countries’ Representatives in Asian Champions League

AbstractNowadays, the International Federation of Football (FIFA) has 208 members, and Asian Football Confederation (AFC) is responsible for organizing and developing football as the most important organization in the old continent. Asian Champions League (ACL) is a football high level competition in Asia. The purpose of this study was to investigate the relationship between the criteria of AFC and the success of countries’ representatives in ACL. This study was casual-comparative and applied. The statistical population included 32 clubs that participated in the 10th preliminary round of ACL. The statistical sample consisted of 11 countries which have representatives in this event. The data gathered from official website of AFC (www.the-afc.com), and the official magazine of Iran Pro League Federation “The Vision of Soccer”. For analysing the data, we utilized K-S, Pearson Correlation Coefficient and Stepwise Multi Regression. The results indicated that there was a significant positive relationship between AFC criteria and the success of countries’ representative in Asian Champions League (ACL). Also, technical standards predict the success of countries’ representative in ACL significantly (p < 0.0001, β = 0.88). It seems that more attention to the technical standards will bring better results for the next seasons