Nonlinear analysis of prestressed concrete deep

Dissertant

Mahmud, Kamal Shihadah

University

University of Technology

Faculty

-

Department

Department of Building and Construction Engineering

University Country

Iraq

Degree

Master

Degree Date

2004

English Abstract

Reinforced concrete deep beams are structural members that are subjected to a relatively high shear besides bending.

Deep beams appear in many structures such as tall building foundations, transfer girders, pile caps, water tanks and bunkers.

The principal objective of the work described in this thesis is to investigate and to get more information and better understanding of the behavior of partially prestressed concrete deep beams by using a numerical analysis technique based on nonlinear finite element method.

The thesis presents a three-dimensional nonlinear finite element model suitable for the analysis of partially prestressed concrete deep beams.

Concrete is modeled by using the 20-node brick elements, while the prestressing steel and ordinary reinforcement bars are modeled as axial members embedded within the concrete element.

Perfect bond was assumed to occur between the concrete and the steel.

The behavior of concrete in compression is simulated by an elastic-plastic work-hardening model followed by perfectly plastic response.

This response is terminated at the onset of crushing.

In tension, a fixed smeared crack model has been used with a tension-stiffening model to represent the retained post-cracking tensile stresses and a shear retention model that modifies the shear modulus of rigidity due to cracking.

The nonlinear equations of equilibrium have been solved by using incremental-iterative technique based on the modified Newton-Raphson method.

The convergence of the solution was controlled by a load convergence criterion.

The numerical integrations have been carried out by using 27-Gaussion point integrations rule.

Different types of partially prestressed concrete deep beams have been analyzed and the finite element solutions were compared with the available experimental results.

Effect of some important numerical property and material parameters has been investigated to study their influence on the predicted load defection curves.

In general, good agreement between the finite element solution and the experimental results has been obtained.

Main Subjects

Civil Engineering

Topics

• Mathematical models

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-305860