Statement of the problem Many partially edentulous situations are present whereby the choice between a removable and a fixed partial denture lies within the delicate balance of a single standing abutment. This abutment is called as a pier abutment. If and when a fixed fixed prosthesis is given in such a case, the retainer over the pier abutment acts as a fulcrum and invariably leads to cement f...

The response of a bridge tower-pier system resting on elastic soil, with a sliding foundation obeying Coulomb's friction law, is studied. The stiffness and damping of the supporting soil is fully taken into account. The action of the suspension bridge cables is equivalent to a horizontal elastic restraint at the top of the tower. The differential equations of motion of the pier are formulated f...

a large number of authors have studied to find out how to control scouring around a pier along direct stream. the objective of this research is then to study a scour pattern around such piers on curves rivers due to the fact that there may be a difference between a flow pattern on a direct line and the meander. thus, this study tries to check whether the use of cable and collar alone and in a c...

In this paper, submerged vanes were placed at the upstream area of a bridge pier located at the 90 degree angle. Then, using the laboratory equipment, a study of flow pattern was conducted throughout the bend, specifically around the pier and submerged vanes. ADV velocimeter was incorporated in order to help measure 3D velocity components. Submerged vanes were installed at distances of 40 and 6...

Controlled rocking of steel braced frames has been proposed for the seismic retrofit of structures. The controlled rocking approach allows a frame to uplift from its support at the base-of-column to foundation interface while displacementbased steel yielding devices are implemented at the base location to control the response. Past studies have focused on analytical investigations of the respon...

The scour phenomenon around bridge piers causes great quantities of damages annually all over the world. Collars are considered as one of the substantial methods for reducing the depth and volume of scour around bridge piers. In this study, the experimental and numerical methods are used to investigate two different shapes of collars, i.e, rectangular and circular, in terms of reducing scour ar...

The hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier were researched. The effects of the prestressed tendon ratio, the longitudinal reinforcement ratio, and the stirrup reinforcement ratio on the hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier have been obtained with the fiber model analysis method. The analysis show...

In many cases, a set of obstacles, such as bridge piers and abutments, are located in the river waterway. Bridge piers disrupt river’s normal flow, and the created turbulence and disturbance causes diversion of flow lines and creates rotational flow. Geometric shape and position of the piers with respect to flow direction and also number of piers and their spacing are effective on changing the ...

Original scientific paper The objectives of this paper are to perform a comparative analysis of the large-scale system of a high-pier railway bridge subjected to stationary and nonstationary spatially varying earthquake excitations using the pseudo-excitation method (PEM), and to estimate whether or not the non-stationary stochastic analysis of the high-pier railway bridges under tri-directiona...

An experimental approach was carried out to study the time development and extension of scouring around a circular pier protected by a collar. The experiments included the study of scouring around an unprotected pier as well as the pier protected with collars located at different levels. Width of collars was 3 times the pier diameter. It was found that with collars, though the scour depth and t...