Results 131 to 140 of about 380 (177)

Refined calculation of time-dependent prestress losses in prestressed concrete girders

Structure and Infrastructure Engineering, 2020
Considering the interaction between concrete shrinkage and concrete creep and between the relaxation of prestressing steel and concrete creep in the prestressed concrete member, a refined method fo...
Mingfang Yang, Jinxin Gong
exaly   +2 more sources

Eigenfrequencies of continuous prestressed concrete bridges subjected to prestress losses

Structures, 2020
Abstract The paper presents a numerical procedure to evaluate the consequences of prestress loss on the frequencies of vibration of continuous prestressed concrete (PSC) bridges. The importance of being able to identify an excessive loss of prestressing, caused for instance by the breaking of some strands, is evident considering that currently the ...
Marco Breccolotti
exaly   +3 more sources

A METHOD FOR PREDICTING PRESTRESS LOSSES IN A PRESTRESSED CONCRETE STRUCTURE

PCI Journal, 1972
A METHOD IS PESENTED FOR PREDICTING ACTUAL PRESTRESS LOSSES IN A PRESTRESSED CONCRETE STRUCTURE. IT USES AVAILABLE INFORMATION ON CONCRETE CREEP AND SHRINKAGE AND STEEL STRESS RELAXATION, AND INCLUDES THE EFFECT OF INTERACTION OF THE VARIOUS FACTORS CONTRIBUTING TO PRESTRESS LOSS.
R. J. Glodowski, J. J. Lorenzetti
openaire   +1 more source

Partial Loss of Prestress

2018
Prestressing a concrete member effectively applies a substantial axial force to the member that is in place for its entire service life. In both pretensioned and post-tensioned methods of prestressing, this prestressing force begins to decline immediately upon its application and continues to decline throughout its service life. This reduction in force
Charles W. Dolan, H. R. Hamilton
openaire   +1 more source

Effect of Non-Prestressed Steel on Prestress Loss and Deflection

PCI Journal, 1977
A simple accurate method is presented for calculating prestress loss, axial strain, and curvature at a cross section of a member containing prestressed as well as nonprestressed steel. Two sets of graphs are given as design aids, and their use is demonstrated by numerical examples.
Maher K. Tadros, Amin Ghali, Walter H. Dilger   +2 more
openaire   +1 more source

Losses in partially prestressed concrete

Canadian Journal of Civil Engineering, 1988
The calculation of prestress losses by the age-adjusted effective modulus method is analyzed and compared with the Ontario highway bridge design code predictions for partially prestressed concrete. Specifically, the effect of nonprestressed reinforcement on prestress losses is studied.
B. DeV. Batchelor, Jayanth Srinivasan, Mark F. Green   +2 more
openaire   +1 more source

UNDERSTANDING THE LOSSES IN PRESTRESSING

PCI Journal, 1969
LOSSES THAT OCCUR IN PRESTRESSED CONCRETE AND ATTEMPTS TO PLACE THEM IN PROPER PERSPECTIVE TO EACH OTHER ARE DISCUSSED. LOSS OF PRESTRESS DUE TO RELAXATION OF STEEL, SHRINKAGE, ELASTIC DEFORMATION AND CREEP IN THE CONCRETE, ANCHORAGE SLIP AND TENDON FRICTION ARE DISCUSSED; METHODS OF EVALUATING THESE LOSSES ARE PRESENTED.
openaire   +1 more source

Prestress Losses in Partially Prestressed High Strength Concrete Beams

PCI Journal, 1993
The results of a comprehensive parametric study on prestress losses in prestressed and partially prestressed high strength concrete beams are reported. Attention is focused on the influence of the partial prestressing ratio (from no prestressing to full prestressing) and the compressive strength of concrete, from 6 ksi (41 MPa) up to 10 ksi (69 MPa ...
Antoine E. Naaman, Ali M. Hamza
openaire   +1 more source

Loss of Prestress, Deflection, and Partial Prestress

1990
This chapter includes discussions of several important, frequently encountered subjects that pertain to the elastic design of simple prestressed concrete flexural members. An engineer who frequently is engaged in the design of prestressed structures will become familiar with these relationships through design experience.
openaire   +1 more source

A Probabilistic Comparison of Prestress Loss Methods in Prestressed Concrete Beams

PCI Journal, 2004
Camber and long-term deflections are directly linked to the loss of prestressing force, a characteristic of all prestressed concrete members. In this investigation, the effects of the inherent variability of the parameters used to estimate prestress loss was studied for two typical bridge beam cases using several prestress loss predictive methods at ...
Christopher G. Gilbertson, Theresa M. (Tess) Ahiborn   +1 more
openaire   +1 more source