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Analysis of the literature has shown that two main factors, which should be taking into consideration in designing of continuous bridges, are the influence of cracking on serviceability of the structures and inelastic behaviour of structural elements. Crack control is often the governing design criterion for the choice of the amount of longitudinal pre-stressing of reinforced concrete bridges as well as for the construction sequence of composite bridges. Present paper investigates cracking behaviour of reinforced concrete decks of continuous bridges over intermediate supports. It should be noted that this section behaves almost as pure tension ties. The paper presents results of complex investigation which has included experimental and numerical analyses of deformations and cracking resistance of reinforced concrete tensile members and a deck slab. Different techniques on crack controlling were analysed. Analysis was showed that the techniques worth predicting deformational behaviour of reinforced concrete members as well as assuring the cracking control in the bridge deck.

Dealing with short-term deformations and the tension-stiffening effect in reinforced concrete (RC), the current study consists of two parts as presented in two separate manuscripts. Based on the test data of more than 300 RC ties, alternative tension-stiffening relationships of different complexity were proposed in the first article (Part I). In the companion manuscript (Part II), a stochastic modeling technique for assessing the deformation response of RC elements, subjected to different combinations of tension and flexure, is proposed. Based on stochastic principles, this technique allows not only to predict the average deformation response, but also to establish bounds of these predictions that are of vital importance for practical problems. The proposed technique is verified with the help of independent test data in order to validate the accuracy of the predictions of deformation, using the tension-stiffening models proposed in Part I of the article. Test specimens with different arrangements of steel or GFRP bars in the tensile zone were considered. The analysis has revealed that the influence of the degree of sophistication of the tension-stiffening models on the analysis results is smaller than the one of an ade- *

The paper presents a simple discrete crack model for analyzing the deformation and crack width of reinforced concrete beams. The model is based on a non-iterative algorithm and uses a rigid-plastic bond-slip law and elastic properties of materials. Curvatures and crack widths predicted by the proposed technique were checked against the test results of six experimental beams, reported by the authors and other investigators. The article also proposes and discusses a numerical procedure for deriving the average bond stress with reference to the test data. Serviceability analysis resulted in a reasonable agreement on the test measurements. Santrauka Straipsnyje pateikiamas supaprastintas diskrečiųjų plyšiu modelis gelžbetoninių sijų deformacijų ir plyšio pločio analizei. Modelis pagrįstas neiteraciniu algoritmu, remiantis standžiai plastiniu sukibimo desniu ir tampriosiomis medžiagų savybėmis. Remiantis skirtingų autorių atliktais eksperimentiniais duomenimis, modelis patikrintas skaičiuojant gelžbetoninių sijų kreivius ir plyšio pločius. Apskaičiuotos kreivių ir plyšio pločių reikšmės gana tiksliai sutapo su eksperimentiniais rezultatais. Taip pat pasiūlytas originalus vidutinių sukibimo įtempių apskaičiavimo metodas, remiantis eksperimentiniais lenkiamujų gelžbetoninių sijų bandymo rezultatais.