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In the modern construction industry, lightweight aggregate concrete (LWAC) is often used in the production of load-bearing structural members. LWAC can be up to 40% lighter by volume in comparison to normal strength concrete. On the other hand, the lack of adequate numerical models often limits the practical application of innovative building materials, such as lightweight concrete, in real projects. This trend is due to the uncertainties in design standard methods and calculation errors, the level of which is generally unacceptable to civil engineers in terms of safety and reliability. In the present paper, a comparative numerical deformation analysis of a full-scale bridge deck slab and girder has been carried out. Using the physical model proposed by the authors and the finite element software ATENA, the deformations of full–scale lightweight and traditional reinforced concrete elements under short-term effects of permanent and variable loads was compared. Depending on the safety and serviceability limit requirements, it was found that the amount of longitudinal reinforcement in lightweight reinforced concrete elements can be reduced compared to normal reinforced concrete elements with the same parameters. The results of the numerical analysis show that the deformation analysis model proposed by the authors can be a reliable tool for the design of lightweight concrete flexural members by selecting the optimum geometrical and reinforcement parameters limited by the stiffness condition.

This paper presents a case study on the behaviour of precast reinforced columns with non-conventional cross-section. An experimental program was developed to verify the serviceability and ultimate limit states of these columns, loaded with eccentric compression forces. In addition, results obtained through a theoretical model based on the Brazilian standard ABNT NBR 6118:2014 and a Finite Element numerical model using ANSYS software were presented. Analysis of the results showed that the proposed models satisfactorily predicted column behaviour. However, the ultimate strength of the column could not be determined due to limitations in the formulation of the theoretical model. The numerical model presented good agreement with the experimental results, both in serviceability and in ultimate limit state

Бетон је један од најчешће коришћених материјала данашњице. Међутим, током производње цемента, испушта се приближно једна тона CO2 за сваку тону произведеног портланд цементног клинкера. До сада је уложено пуно труда у проналажење одрживих решења за бетон као конструкцијски материјал. Сви ови напори имају за циљ унапређења животне средине на исти начин: очувањем природних ресурса, смањењем емисије CO2 и смањењем количине насталог отпада. Сви ови циљеви се могу постићи употребом летећег пепела као делимичне замене цемента у бетону: коришћењем отпада уместо природних ресурса за производњу бетона, смањењем емисије CO2 кроз смањење коришћења портланд цемента и смањењем количине депонованог пепела. Управо из наведених разлога, данас је свеприсутна општа тежња замене већих количина портланд цемента у бетону различитим замењујућим цементним материјалима (ЦМ). Бетон са великим садржајем летећег пепела (БВСЛП)—бетон са најмање 50% летећег пепела у укупној маси ЦМ—постао је једна од најперспективнијих одрживих алтернатива конвенционалном цементом бетону. Преглед постојеће литературе и расположивих извора показао је да се БВСЛП тренутно углавном користи као део темеља конструкција. Међутим, потребно је још доста истраживања да би са сигурношћу могао да се примењује у грађевинској индустрији као конструкцијски бетон. Већина истраживања спроведених до сада усмерена је на одређивање физичких и механичких својстава БВСЛП. Кроз ограничен број студија спроведено је тестирање конструктивних елемената у пуној величини произведених од БВСЛП како би се утврдила његова потенцијална употреба у армиранобетонским конструкцијама. Главна сврха овог истраживања била је процена могућности примене БВСЛП као бетона за примену у конструкцијама... Concrete is the most widely used construction material today. However, during cement production, approximately one ton of CO2 is released for each ton of Portland cement clinker produced. So far, immense effort has been put into finding sustainable solutions for concrete as a structural material. All of these efforts aim at the same environmental improvements: preservation of natural resources, lowering of CO2 emissions, and decreasing the amount of generated waste. With fly ash as a partial replacement of cement in concrete all these aims can be accomplished: using waste instead of natural resources for concrete production, lowering CO2 emissions through the reduction of Portland cement use and decreasing the amount of deposited fly ash in landfills. It is for these reasons that today there is a general trend of replacing higher amounts of Portland cement in concrete with different supplementary cementitious materials (CM). High volume fly ash concrete (HVFAC)—concrete with at least 50% of fly ash in total CM mass—has become one of the most promising sustainable alternatives to conventional concrete. Reviewing the existing literature and available sources revealed that HVFAC is currently mostly used on construction sites as a part of foundations. However, much more research is still needed for its safe application in the construction industry as structural concrete. Most research so far focused only on the evaluation of HVFAC physical and mechanical properties. Only a limited number of studies implemented full-scale testing of structural members produced with HVFAC to determine its potential use in reinforced concrete structures. The main purpose of this research was to evaluate HVFAC as concrete for structural application. This thesis presents an experimental program developed in two phases. In the first phase, research was performed in order to define the process of developing structural-grade HVFAC mix design using a class F fly ash obtained from one power plant in Serbia...

In the present trend of constructing taller and longer structures, the application of lightweight aggregate concrete is becoming an increasingly important advanced solution in the modern construction industry. In engineering practice, the analysis of lightweight concrete elements is performed using the same algorithms that are applied for normal concrete elements. As an alternative to traditional engineering methods, nonlinear numerical algorithms based on constitutive material models may be used. The paper presents a comparative analysis of curvature calculations for flexural lightweight concrete elements, incorporating analytical code methods EN 1992-1 and ACI 318-19, as well as a numerical analysis using the constitutive model of cracked tensile lightweight concrete recently proposed by the authors. To evaluate the adequacy of the theoretical predictions, experimental data of 51 lightweight concrete beams of five different programs reported in the literature were collected. A comparison of theoretical and experimental results showed that the most accurate predictions are obtained using numerical analysis and the constitutive model proposed by the authors. In the future, the latter algorithm can be used as a reliable tool for improving the design standard methods or numerical modeling of lightweight concrete elements subjected to short-term loading., This article belongs to the Special Issue Advances in Lightweight Aggregate Concrete, The study was performed within the project No. 09.3.3-LMT-K-712-01-0145 that has received funding from European Social Fund under grant agreement with the Research Council of Lithuania (LMTLT).

This paper introduces the recent state of research on shrinkage of concrete. It reviews prediction models of shrinkage strain and curvature analysis methods of reinforced concrete members. New test data on concrete shrinkage has been presented. Various factors that influence shrinkage have been discussed. A calculation technique on short‐term deformations of cracked reinforced concrete members including shrinkage has been introduced. The technique is based onlayer modeland smeared crack approach. Shrinkage influence on behaviour of reinforced concrete beams was investigated numerically and compared with test data reported in the literature. It has been shown that shrinkage has significantly reduced the cracking resistance and leads to larger deflections. Santrauka Straipsnyje atlikta betono traukimosi įtakos gelžbetoninių elementų elgsenai analizė, pateikta betono traukimosi deformacijų apskaičiavimo modelių apžvalga, aptarti traukimosi sukeltų kreivių nesimetriškai armuotuose gelžbetoniniuose elementuose apskaičiavimo metodai, taip pat pateikti nauji betono traukimosi eksperimentinių tyrimų duomenys. Aptarti veiksniai, turintys įtaką traukimosi deformacijoms, aprašytas supleišėjusių gelžbetoninių elementų trumpalaikių deformacijų apskaičiavimo algoritmas, rodantis traukimosi įtaką. Algoritmas pagrįstas sluoksnių modeliu ir vidutinių deformacijų koncepcija. Traukimosi įtaka gelžbetoninių sijų elgsenai nagrinėta, taikant normų bei sluoksnių metodus. Teoriniai rezultatai palyginti su literatūroje paskelbtais eksperimentinių tyrimų rezultatais. Parodyta, kad betono traukimasis gerokai sumažina trumpalaike apkrova veikiamų gelžbetoninių sijų atsparumą pleišėjimui bei lemia didesnes įlinkių reikšmes. First Published Online: 14 Oct 2010 Reikšminiai žodžiai: traukimasis, gelžbetonis, pleišėjimas, trumpalaikis apkrovimas, valkšnumas.

Dissolution of soluble substrates such as gypsum presents a major hazard to dams in many parts of the world. This research simulates hypothesised conditions beneath the Mosul Dam, northwest Iraq, where collapse of a karstic system associated with continuous fresh water supply from its reservoir is a recognised problem. Gypsum rocks from northern Iraq and similar rocks from Bantycock gypsum mine, UK, were analysed for short-term mechanical response following immersion (5 to 50 weeks) and long-term loading during immersion (maximum 50 weeks). New experimental devices were developed from a conventional oedometer. Cylinder samples provided a proxy for massive gypsum strata. Samples were permanently submerged at atmospheric water pressure, with groundwater recharge, flow and dissolution simulated by regular changes of water. Stress on each sample was progressively increased to a maximum of 2688 kPa. Small increases in strain were recorded by the end of each test but no failures occurred within 60 days. However, notable failure due to atmospheric water pressure and axial stress occurred over long time periods. Visible physical changes included a decrease in sample mass and volume. Similar change was recorded in ultrasonic velocities. These indicate that gypsum collapse risk beneath dams requires prolonged exposure to dissolution. The modified device performed well and was robust, and demonstrates that such a modification can provide a simple low cost system for conducting laboratory creep tests on weak rocks.

Traditional steel reinforcement does not resist corrosion and its resources are limited; therefore, carbon, glass, aramid and basalt fibre reinforced polymer bars were developed. The composite reinforcement has a high tensile strength and resistance to electromagnetic fields. Different kinds of materials and application of various surface coatings are used in the production of the composite bars. This results in different adhesion to concrete and mechanical properties of composite bars. In comparison with steel reinforcement, glass, aramid and basalt fibre reinforced polymer bars have a lower modulus of elasticity. Thus, structural rigidity provided by these bars is smaller in respect to reinforced concrete elements. Current reinforced concrete design codes and recommendations are based on empirical and simplified methods of strain evaluation, which may be inadequate for design of structures with composite bars. In this paper, an adequacy of the empirical models was checked against the experimental data of concrete beams reinforced with composite bars. The moment-curvature data of 52 beams reported in the literature and conducted by the authors were used for assessment of accuracy of design methods. In order to perform the analysis, different methods from design codes (European (LST 2007), American (ACI Committee 318 2011) and Russian (NIIZhB 2006)) and recommendations (Italian (CNR 2007) and American (ACI Committee 440 2006)) have been selected. The results of the investigation will provide engineers with more information on design of concrete beams with fibre reinforced polymer bars. This will encourage an extensive use of these innovative materials in different types of structures. Santrauka Tradicinė plieninė armatūra nėra atspari korozijai, jos iŠtekliai yra riboti, todėl buvo sukurti polimeriniai strypai, armuoti anglies, stiklo, bazalto arba aramido pluoŠtu. Ši kompozitinė armatūra pasižymi dideliu tempiamuoju stipriu ir atsparumu elektromagnetiniam laukui. Kompozitinių strypų gamyboje naudojamos skirtingos medžiagos ir taikomi įvairūs pavirŠiaus dengimo būdai, skiriasi jų mechaninės bei sukibimo su betonu savybės. Lyginant su plienine armatūra, stiklo, aramido ir bazalto kompozitiniai strypų tamprumo modulis yra mažesnis, todėl tokiais strypais armuotų konstrukcijų standumas taip pat yra mažesnis nei gelžbetoninių konstrukcijų. Dabartiniuose gelžbetoninių konstrukcijų projektavimo reglamentuose taikomi empiriniai supaprastinti deformacijų nustatymo metodai gali būti netinkami konstrukcijoms, armuotoms polimerine armatūra, projektuoti. Šiame darbe, naudojant mokslinėse publikacijose surinktų 46 eksperimentinių tyrimų ir autorių atliktų 6 sijų bandymų duomenis, buvo įvertintas kompozitais armuoto betono elementų įlinkių skaičiavimo metodų tikslumas. Analizei atlikti buvo pasirinkti Europos (LST EN 1992-1-1:2005), JAV (ACI 318M-11) ir Rusijos (SP 52-101-2003) armuotojo betono konstrukcijų projektavimo normų bei Italijos (CNR-DT 203/2006) ir JAV (ACI 440.1R-06) projektavimo rekomendacijų metodai. Gauti analizės rezultatai suteiks projektuotojams iŠsamesnę informaciją apie kompozitais armuotų betoninių elementų projektavimą, skatins didins Šių inovatyvių medžiagų naudojimo apimtį įvairiose statybinėse konstrukcijose. Reikšminiai žodžiai:nemetalinė strypinė armatūra,projektavimo normos,eksperimentų duomenys,įlinkiai,armuotasis betonas,tikslumo analizė,trumpalaikė apkrova

Recikliranje betonskog otpada je jedno od održivih rešenja za rastuće probleme sa deponijama građevinskog otpada i nekontrolisano iskorišćavanje prirodnih resursa. Rezultat procesa je agregat od recikliranog betona koji se trenutno dominantno koristi za podloge puteva i nekonstruktivne betonske elemente. Sa stanovišta zaštite resursa, smanjenja energije i razvoja ekološke svesti, važno je istražiti da li se beton na bazi recikliranog agregata može koristiti za elemente armiranobetonskih konstrukcija. Predmet istraživanja u ovoj disertaciji su elementi konstrukcije, tačnije gredni nosači napravljeni od betona na bazi recikliranog agregata (RAC) i njihovo ponašanje pod dejstvom kratkotrajnog opterećenja do loma savijanjem ili smicanjem. Formirana je baza podataka i obavljena statistička analiza o mehaničkim svojstvima RAC betona u odnosu na uporedne betone sa prirodnim agregatom (NAC). Eksperimentalni rad obuhvatio je ispitivanje recikliranog agregata, betona na bazi recikliranog agregata i grednih nosača napravljenih od takvog betona. Rezultati ispitivanja svojstava agregata i probna ispitivanja fizičko-mehaničkih svojstava serija RAC i NAC betona poslužili su kao ulazni parametar za projektovanje sastava 3 betonske mešavine sa 0%, 50% i 100% recikliranog agregata krupne frakcije, iste projektovane čvrstoće pri pritisku. Ukupno je do loma ispitano 18 greda, statičkog sistema prosta greda, raspona 3.0 m. Od toga, napravljene su 3 serije od po 3 grede sa različitom količinom podužne armature (0.28%, 1.46% i 2.54%). Koncept ispitivanja postavljen je tako da se faznim povećanjem opterećenja dođe do loma nosača usled savijanja u sredini raspona. Takođe, napravljene su 3 serije od po 3 grede od betona sa 0%, 50% i 100% krupnog RAC i sa različitom količinom poprečne armature (0%, 0.14% i 0.19%), predviđenih za ispitivanje smičuće nosivosti. Izvršeno je poređenje zavisnosti sila-pomeranje, slika prslina, ugiba, dilatacija u betonu i armaturi, oblika loma i graničnih nosivosti greda od klasičnog i RAC betona, bazirano na sopstvenim i drugim rezultatima ispitivanja. Testirana je mogućnost primene savremenih propisa koji se odnose na NAC betone na gredne RAC elemente, kroz poređenje analitičkih predikcija i eksperimentalnih vrednosti momenta savijanja pri pojavi prve prsline, ugiba, graničnih momenata savijanja i granične smičuće sile. Takođe, izvršeno je poređenje sopstvenih i drugih rezultata eksperimentalnih ispitivanja osnovnih parametara nosivosti greda koje su dominantno izložene savijanju ili smicanju... Recycling of waste concrete is one of the sustainable solutions for the growing waste disposal crisis and depletion of natural aggregate sources. As a result, recycled concrete aggregate (RCA) is produced, and so far it has mostly been used in low-value applications such as for the pavement base. But, from the standpoint of promoting resource and energy savings and environmental preservation, it is essential to study whether a concrete made of recycled aggregates - recycled aggregate concrete (RAC) can be effectively used as a structural material. Structural reinforced concrete elements were in the focus of this investigation, i.e. beam girders made of RAC and their behaviour up to flexural and shear failure under short-time loading. A very wide data base was formed and statistic analysis of relations between mechanical properties of RAC and corresponding natural aggregate concrete (NAC) was performed. The experimental research consisted of investigations of recycled concrete aggregate, recycled aggregate concrete and structural behaviour of beams made of RAC. Test results of RCA investigation and trial investigations of physical and mechanical properties of RAC were used as basic parameters for the design of 3 concrete mixtures with 0%, 50% i 100% of coarse RCA with the same compressive strength. Full-scale tests were performed on 18 simply supported beams with span of 3.0 m until the failure load due to flexure or shear was reached. Firstly, three series of beams made of three types of concrete and different ratio of flexural reinforcement (0.28%, 1.46% and 2.54%) were formed. Experiment on beams was performed by increasing the load level until flexural failure in the middle of span occurred. Furthermore, three series of beams with different ratio of shear reinforcement (0%, 0.14% i 0.19%) and concrete with 0%, 50% and 100% of coarse RCA were prepared to examine shear behavior. Comparison of load-deflection behavior, crack patterns, service deflections, strains in concrete and reinforcement, failure modes and ultimate flexural and shear capacity of NAC and RAC beams was made. The possibility of using equations from NAC codes to RAC beams was tested by comparison of an analytical expressions and experimental results related to cracking moments, deflections, ultimate bending moments and ultimate shear capacity. The analysis of own and other authors’ test results was performed both on flexural and shear behavior of RAC reinforced concrete beams...

Recycling of waste concrete is one of the sustainable solutions for the growing waste disposal crisis and depletion of natural aggregate sources. As a result, recycled concrete aggregate (RCA) is produced, and so far it has mostly been used in low-value applications such as for the pavement base. But, from the standpoint of promoting resource and energy savings and environmental preservation, it is essential to study whether a concrete made of recycled aggregates—recycled aggregate concrete (RAC) can be effectively used as a structural material. The experimental research presented in this paper is performed in order to investigate the flexural behavior of RAC beams when compared to the behavior of natural aggregate concrete (NAC) beams under short-term loading and consequently the possibility of using RAC in structural concrete elements. Three different percentages of coarse RCA in total mass of coarse aggregate in concrete mixtures (0 %—NAC, 50 %—RAC50, and 100 %—RAC100), and three different reinforcement ratios (0.28, 1.46, and 2.54 %) were the governing parameters in this investigation. Full-scale tests were performed on nine simply supported beams until the failure load had been reached. Comparison of load-deflection behavior, crack patterns, service deflections, failure modes and ultimate flexural capacity of NAC and RAC beams was made based on our own and other researchers’ test results. The results of conducted analysis showed that the flexural behavior of RAC beams is satisfactory comparing to the behavior of NAC beams, for both the service and ultimate loading. It is concluded that, within the limits of this research, the use of RAC in reinforced concrete beams is technically feasible.

Gelžbetonis yra kompozitinė medžiaga, kurios komponentai yra betonas ir plieninė armatūra. Kaip žinoma, betono stipris tempiant yra 1020 kartų mažesnis nei stipris gniuždant. Atrodytų, kad tempiamojo betono įtaka, atlaikant įrąžas skerspjūvyje, yra nereikšminga. Iš tiesų, nustatant lenkiamųjų elementų stiprumą normaliniame pjūvyje, tempiamo betono įtempių galima nevertinti. Kita vertus, skaičiuojant įlinkius, neįvertinus tempiamojo betono įtakos, gali būti daroma didesnė nei 100 % paklaida. Adekvatus supleišėjusio tempiamojo betono įtakos įvertinimas, nustatant trumpalaike apkrova veikiamų gelžbetoninių elementų deformacijas, yra bene svarbiausia ir sudėtingiausia problema. Plyšio vietoje betonas negali atlaikyti tempimo įtempių, todėl visą įrąžą atlaiko armatūra. Kadangi plyšyje ir gretimuose pjūviuose armatūra praslysta betono atžvilgiu, kontakto zonoje atsiranda tangentiniai įtempiai. Šie įtempiai perduodami betonui, todėl jis atlaiko tempimo įtempius. Armatūros ir betono sąveika ruožuose tarp plyšių standina gelžbetoninį elementą. Supleišėjusio betono gebėjimas atlaikyti tempimo įtempius vadinama tempimo sustandėjimu (angl. tension stiffening). Šis efektas dažniausiai modeliuojamas supleišėjusio betono įtempių ir deformacijų diagrama, taikant vidutinių plyšių koncepciją. Tuomet neatsižvelgiama į diskrečius plyšius, o supleišėjęs betonas traktuojamas kaip ortotropinė medžiaga su pakitusiomis savybėmis. Dauguma tempimo sustandėjimo modelių įvertina betono įtempių... [toliau žr. visą tekstą] Modelling behaviour of cracked tensile concrete is a complicated issue. Due to bond with reinforcement, the cracked concrete between cracks carries a certain amount of tensile force normal to the cracked plane. Concrete adheres to rein-forcement bars and contributes to overall stiffness of the structure. The phe-nomenon, called tension-stiffening, has significant influence on the results of short-term deformational analysis. Assumption of a tension-stiffening law has great influence on numerical results of load – deflection behaviour of reinforced concrete members subjected to short – term loading. Under wrong assumption of this law, errors in calculated deflections, particularly for lightly members, may exceed 100 %. Most known tension-stiffening relationships relate average stresses to average strains. However, some experimental and theoretical investi-gations have shown that tension-stiffening may be affected by other parameters. The scientific supervisor of the thesis has proposed a tension-stiffening model depending on reinforcement ratio. This model has been developed using experi-mental data reported in the literature. Besides, concrete shrinkage effect was not taken into account. The main objective of this PhD dissertation is to propose a tension-stiffening law for bending RC members subjected to short-term loading with eliminated concrete shrinkage effect.

Based on a method proposed by the authors, a new tension-stiffening law has been proposed for short-term deformational analysis of flexural reinforced concrete members. It was derived from experimental moment-curvature diagrams of RC beams reported by the authors. A quantitative dependence has been established between the length of the descending branch and the reinforcement ratio. The proposed relationship has been applied in a simple engineeing technique based on layered approach and principles of strength of materials. To assess accuracy of the technique, deflections/curvatures have been calculated for a large number of experimental reinforced concrete beams reported in the literature. Comparison has been carried out with proposed relationship and design code methods such as the ACI 318, Eurocode 2 and SP 52-101 (new Russian code).

Recycling of waste concrete is one of the sustainable solutions for growing waste disposal crisis and depletion of natural aggregate sources. As a result of that process, recycled aggregate (RCA) is produced and it is used mostly in low-value application such as for pavement base. But from the viewpoint of promoting resource and energy saving and environmental preservation, it is essential to study if a concrete made of recycled aggregates - recycled aggregate concrete (RAC) can be effectively used as a structural material. Some experimental studies concerning flexural and shear behaviour of reinforced concrete beams made of recycled aggregate concrete are presented in this paper. Comparison of load-deflection behaviour, crack width and spacing, failure modes and ultimate bending and shear capacity of the beams made of natural (NAC) and recycled aggregate concrete is performed. On the basis of the limited reported test results, it is concluded that the behaviour of RAC beams made of concrete with only coarse aggregate recycled is satisfactory comparing to the behaviour of NAC beams, for service and ultimate short-term loading both. . Jedno od održivih rešenja za probleme odlaganja građevinskog otpada i iscrpljivanje prirodnih nalazišta agregata predstavlja postupak recikliranja otpadnog betona. Kao rezultat, dobija se agregat od recikliranog betona (ARB) koji se najčešće koristi za nasipe, kao podloga puteva itd. Međutim, sa aspekta uštede prirodnih resursa i energije, kao i zaštite životne sredine, važno je istražiti da li se betoni na bazi recikilranog agregata (BRA) mogu koristiti kao konstrukcijski betoni. U radu su predstavljena dosadašnja eksperimentalna istraživanja ponašanja greda od BRA pod uticajem kratkotrajnog opterećenja, u fazi eksploatacije i fazi loma. Izvršena je uporedna analiza deformacijskih karakteristika (ugiba), stanja prslina (širina, razmak) i graničnih nosivosti greda od betona na bazi prirodnog agregata (BPA) i greda od betona na bazi recikliranog agregata. Na osnovu do sada izvršenog malog broja eksperimentalnih ispitivanja, može se zaključiti da je ponašanje greda od BRA kod kojih je samo krupni agregat bio recikliran, zadovoljavajuće u odnosu na ponašanje odgovarajućih greda od BPA, i to kako za eksploataciono, tako i za granično kratkotrajno opterećenje. .

This paper introduces the recent state of research on shrinkage of concrete. It reviews prediction models of shrinkage strain and curvature analysis methods of reinforced concrete members. New test data on concrete shrinkage has been presented. Various factors that influence shrinkage have been discussed. A calculation technique on short-term deformations of cracked reinforced concrete members including shrinkage has been introduced. The technique is based on layer model and smeared crack approach. Shrinkage influence on behaviour of reinforced concrete beams was investigated numerically and compared with test data reported in the literature. It has been shown that shrinkage has significantly reduced the cracking resistance and leads to larger deflections., Lietuviška santrauka. Straipsnyje atlikta betono traukimosi įtakos gelžbetoninių elementų elgsenai analizė, pateikta betono traukimosi deformacijų apskaičiavimo modelių apžvalga, aptarti traukimosi sukeltų kreivių nesimetriškai armuotuose gelžbetoniniuose elementuose apskaičiavimo metodai, taip pat pateikti nauji betono traukimosi eksperimentinių tyrimų duomenys. Aptarti veiksniai, turintys įtaką traukimosi deformacijoms, aprašytas supleišėjusių gelžbetoninių elementų trumpalaikių deformacijų apskaičiavimo algoritmas, rodantis traukimosi įtaką. Algoritmas pagrįstas sluoksnių modeliu ir vidutinių deformacijų koncepcija. Traukimosi įtaka gelžbetoninių sijų elgsenai nagrinėta, taikant normų bei sluoksnių metodus. Teoriniai rezultatai palyginti su literatūroje paskelbtais eksperimentinių tyrimų rezultatais. Parodyta, kad betono traukimasis gerokai sumažina trumpalaike apkrova veikiamų gelžbetoninių sijų atsparumą pleišėjimui bei lemia didesnes įlinkių reikšmes.