Nonlinear Finite Element Analysis of Reinforced Concrete Slab Strengthened with Shear Bolts

This paper presents an implementation of a rational three-dimensional nonlinear finite element model for evaluating the behavior of reinforced concrete slabs strengthened with shear bolts under transverse load. The concrete was idealized by using eight-nodded brick elements. While both flexural reinforcement and the shear bolts were modeled as truss elements, a perfected bond between brick elements and truss elements was assumed. The nonlinear behavior of concrete in compression is simulated by an elasto-plastic work-hardening model, and in tension a suitable post-cracking model based on tension stiffening and shear retention models are employed. The steel was simulated using an elastic-full plastic model. The validity of the theoretical formulations and the program used was verified through comparison with available experimental data, and the agreement has proven to be good. A parametric study has been also carried out to investigate the influence of the shear bolts’ diameter and number of bolts’ rows around the column-slab connection, on the ductility and ultimate load capacity of slabs

Swelling and Geotechnical Cartography of Saida Soils

The urban expansion and the increase in population led the urbanization to use the spaces called “at risk”.The integration and the treatment of ground’s movements constitute an important characteristic of the equilibrium established by nature. In the Saïda town (Algeria), many projects built on grounds with problems showed signs of degradations such as cracks in structures. These degradations led to the total destruction of the buildings. The principal causes of these disasters are: the expansive nature of soils and landslides, and the disaster phenomenon not considered in the first study of these constructions. The damage also touched road embankments, highways and foundations. In order to solve these problems, it was necessary to propose a geotechnical and risk map for the ZHUN EAST (ESSALAM city, Saïda), a city which includes several yards of the soil with problems, using the Geographical Information Systems (GIS/MapInfo). These tools enable us to express the perception of space and data processing, and consequently the cartography is carried out in an optimal way. These geotechnical and risk maps have a great part of importance in all levels of a study as information, working paper, alert, and especially is a tool for the decision-making aid, by expressing tendencies and orientations. They enabled us to give a field representing the active and potential movements with a hierarchy of risks to guide the developer and the engineer

Reliability and punching shear resistance of slabs in non linear domain

U radu se numerički ocjenjuje otpornost ploča na proboj te se prikazuje usporedba s predviđanjima utemeljenima na nekim propisima za projektiranje. Analizira se i interakcija glavnih parametara koji utječu na proboj i vrstu sloma ploča. Rezultati analize pouzdanosti prikazani su pomoću indeksa pouzdanosti za razne razine Pu/Pflex. Uz analizu pouzdanosti, provedena je i analiza osjetljivosti u smislu različitih razina opterećenja kako bi se na taj način istražio utjecaj osnovnih varijabli na rezultate.In this paper, the punching shear resistance of slabs is numerically evaluated and compared to predictions specified in some design codes. The interaction of major parameters that affect the punching shear behaviour and failure mode of slabs is also studied. Reliability analysis results are presented in terms of the reliability index for various levels of Pu/Pflex. In addition to the reliability analysis, the sensitivity analysis is carried out in terms of different load levels so as to study the effect of main variables on the results

Non-linear finite element analysis of reinforced concrete members and punching shear strength of HSC slabs

A rational three-dimensional nonlinear finite element model (NLFEAS) is used for evaluating the behavior of high strength concrete slabs under monotonic transverse load. The non-linear equations of equilibrium have been solved using the incremental-iterative technique based on the modified Newton-Raphson method. The convergence of the solution was controlled by a load convergence criterion. The validity of the theoretical formulations and the program used was verified, through comparison with results obtained using ANSYS program and with available experimental test results. A parametric study was conducted to investigate the effect of different parameters on the behavior of slabs which was evaluated in terms of loaddeflection characteristics, concrete and steel stresses and strains, and failure mechanisms. Also, punching shear resistance of slabs was numerically evaluated and compared with the prediction specified by some design codes

Non-linear finite element analysis of reinforced concrete members and punching shear strength of HSC slabs

A rational three-dimensional nonlinear finite element model (NLFEAS) is used for evaluating the behavior of high strength concrete slabs under monotonic transverse load. The non-linear equations of equilibrium have been solved using the incremental-iterative technique based on the modified Newton-Raphson method. The convergence of the solution was controlled by a load convergence criterion. The validity of the theoretical formulations and the program used was verified, through comparison with results obtained using ANSYS program and with available experimental test results. A parametric study was conducted to investigate the effect of different parameters on the behavior of slabs which was evaluated in terms of loaddeflection characteristics, concrete and steel stresses and strains, and failure mechanisms. Also, punching shear resistance of slabs was numerically evaluated and compared with the prediction specified by some design codes