The National Bridge Inventory (NBI) includes more than 600,000 bridges within the United States of Prestressed concrete girder bridges represent one of the most widely used bridge systems. The majority of these girder bridges were constructed using 0.5 and 0.6 inch diameter strands. The main impediments to using larger strand diameters are: 1) bed capacities, 2) lack of structural knowledge reg...

this paper describes experimental and numerical investigations on two specimens of frames composed of steel reinforced concrete beam and angle-steel concrete column under horizontal low cyclic loading. based on the test results, the relationship curves of the horizontal load-displacement and the failure modes are acquired. meanwhile the hysteretic behaviors, skeleton curves, stiffness degradati...

This study develops a new approach for forecasting shear Strength of concrete beam without stirrups based on the artificial neural networks (ANN). Proposed ANN considers geometric and mechanical properties of cross section and FRP bars, and shear span-depth ratio. The ANN model is constructed from a set of experimental database available in the past literature. Efficiency of the ANN model was c...

in this paper a new method based on strut-and-tie model (stm) is proposed to determine the shear capacity of simply supported rc deep beams and an efficiency factor for concrete with considering the effect of web reinforcements. it is assumed that, the total carried shear force by rc deep beam provided by two independent resistance, namely diagonal concrete strut due to strut-and-tie mechanism ...

The ultra-high strength self-compacting concrete, UHSSCC is the new generation type of concrete with a compressive strength higher than 80MPa. The application of this type of concrete on the serviceability state in CFRP strengthened unbonded post-tensioned indeterminate I-beam is monitored and the results are compared theoretically using different standards. For this aim, full scale I-beam of 9...

This paper presents a method for evaluating the reliability of an in-service highway bridge that considers the resistance capacity loss due to various corrosive environments. To demonstrate the application of the suggested method, a pre-stressed concrete-I (PSC-I) type girder was selected as a sample bridge. An analytical procedure was developed to quantitatively evaluate the performance degrad...

The segmental prestressed concrete box girder of Koror-Babeldaob (KB) Bridge in Palau, which had the record span of 241 m (791 ft.), presents a striking paradigm of serviceability loss due to excessive multi-decade deflections. The data required for analysis have recently been released and are here exploited to show how the analysis and design could be improved. Erected segmentally in 1977, thi...

Shape memory alloys (SMAs) are unique smart materials that have many advantages, such as ability to resist large strains without leaving residual strains and ability to recover original form. However, the high costs of SMAs have limited their usage. This paper evaluates the behavior of concrete structures equipped with SMAs in an optimal manner as they are being used along the plastic hinge of ...

performance of structures during recent earthquakes shows that the effect of vertical component of earthquake (vce) could be considered as one of the main causes of bridges collapse. in most of bridge design codes, for seismic analysis of bridges, vce is not taken into account or a distinguished method isn’t presented for assessment of vce. in the present work, the effect of vce on two existing...