Seismic Performance of Stainless and Conventional Steel Energy Dissipation Bars in Precast Segmental Bridge Columns

Seismic Performance of Stainless and Conventional Steel Energy Dissipation Bars in Precast Segmental Bridge Columns
Author: Yihui Zhou
Publisher:
Total Pages: 327
Release: 2011
Genre:
ISBN:

The use of stainless steel reinforcing bars in seismic applications has recently attracted much attention in the civil engineering community due to its superior material properties, including high corrosion resistance and high specific strength. However, as with all new materials, a number of shortcomings are unavoidable, such as high initial costs, unknown low-cycle fatigue behavior, uncertain ductility properties and unidentified bond-slip behavior between the embedded bar and grouted duct in precast concrete element for use in segmental bridge members. The performance of precast segmental post-tensioned concrete bridge columns in seismic regions has been investigated by many other researchers. Mild steel energy dissipation bars (ED bars) that were continuous across the column segment joints were added into the columns to increase the hysteretic energy dissipation capacity.^In phase Iexperimental study, mechanical properties and low-cycle fatigue behavior of Talley S24100, Talley 316LN, Talley 2205 and Arminox UNS S32304 stainless reinforcing steel, A706 carbon black reinforcing steel, and MMFX II high strength, corrosion resistant reinforcing steel were investigated. Talley S24100 was found to obtain the highest ductility and the best low-cycle fatigue performance among the steels investigated. Therefore, compared to A706, Talley S24100 was considered to be the superior substitute material for ED bars. Succeeding phase II and phase III study on the bond-slip response of stainless steel reinforcing bars in grouted ducts of precast concrete element was then carried out with a focus on the influence of various duct/bar diameter ratios and different embedment lengths.^A seriesof monotonic pull-out and tension cyclic tests were conducted to investigate the constitutive bond-slip relationship between the bar and duct confined grout and their further applications under seismic loadings. Results showed that for A706 and Talley S24100 steels, both the duct/bar diameter ratio and embedment length influenced the bond-slip behavior in the monotonic pull-out tests. A one-dimensional nonlinear bond spring model exhibited a good performance in simulating the test results. In addition to the conventional bond-slip model, an "end-slip model" is also proposed in this study to describe the loaded end slip behavior of a bar anchored in grouted duct with a relatively deep embedment (12,16and 24 db). Each bond-slip and end-slip model has a five segment structure (each segment is linear). Recommended design equations were developed for development lengths for A706 and Talley S24100 reinforcing steels, respectively.^The local ED bar strains at different column top drift levels were investigated.

Bridge Maintenance, Safety, Management, Resilience and Sustainability

Bridge Maintenance, Safety, Management, Resilience and Sustainability
Author: Fabio Biondini
Publisher: CRC Press
Total Pages: 4119
Release: 2012-06-21
Genre: Technology & Engineering
ISBN: 0203103386

Bridge Maintenance, Safety, Management, Resilience and Sustainability contains the lectures and papers presented at The Sixth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2012), held in Stresa, Lake Maggiore, Italy, 8-12 July, 2012. This volume consists of a book of extended abstracts (800 pp) Extensive collection of revised expert papers on recent advances in bridge maintenance, safety, management and life-cycle performance, representing a major contribution to the knowledge base of all areas of the field.

Energy Dissipation Capacity Of RC Bridge Columns Under Seismic Demand

Energy Dissipation Capacity Of RC Bridge Columns Under Seismic Demand
Author: Syed Ali
Publisher: LAP Lambert Academic Publishing
Total Pages: 308
Release: 2015-07-15
Genre:
ISBN: 9783659546198

Field studies were carried out to investigate various parameters of bridges found in northern part of Pakistan. After the Kashmir earthquake of Mw7.6 in 2005, detailed field investigations of seismic performance of bridges was undertaken. A mathematical function to define the functionality of bridges was developed which is helpful for quantifying the seismic resilience of bridges. Criterion for minimum required functionality for different bridges and limit states were defined for large rare earthquake and for moderate occasional earthquakes. From the field data, a series of experimental studies were undertaken on scaled models representing typical bridge pier of low concrete strength having single solid circular section. The experimental results of hysteresis and dynamic characteristics are used to establish expected prototype bridge columns. Detailed numerical studies were undertaken in which inelastic nonlinear dynamic analyses were carried out on calibrated numerical model. Period based response modification factors are established. This research is sponsored by Higher Education Commission of Pakistan & facilitated by University of Engineering & Technology Peshawar.

Reinforced Concrete Structures

Reinforced Concrete Structures
Author: Robert Park
Publisher: John Wiley & Sons
Total Pages: 794
Release: 1991-01-16
Genre: Technology & Engineering
ISBN: 9780471659174

Sets out basic theory for the behavior of reinforced concrete structural elements and structures in considerable depth. Emphasizes behavior at the ultimate load, and, in particular, aspects of the seismic design of reinforced concrete structures. Based on American practice, but also examines European practice.

Seismic Behavior of Circular Reinforced Concrete Bridge Columns Under Combined Loading Including Torsion

Seismic Behavior of Circular Reinforced Concrete Bridge Columns Under Combined Loading Including Torsion
Author: Suriya Prakash Shanmugam
Publisher:
Total Pages: 634
Release: 2009
Genre: Bridges
ISBN:

"Reinforced concrete (RC) columns of skewed and curved bridges with unequal spans and column heights can be subjected to combined loading including axial, flexure, shear, and torsion loads during earthquakes. The combination of axial loads, shear force, and flexural and torsional moments can result in complex failure modes of RC bridge columns. This study carried out experimental and analytical studies to investigate the seismic performance of circular RC columns under combined loading including torsion. The main variables considered here were (i) the ratio of torsion-to-bending moment (T/M), (ii) the ratio of bending moment-to-shear (M/V) or shear span (H/D), and (iii) the level of detailing for high and moderate seismicity (high or low spiral ratio). In particular, the effects of the spiral reinforcement ratio and shear span on strength and ductility of circular RC columns under combined loading were addressed. In addition, the effects of torsional loading on the bending moment-curvature, ductility, and energy dissipation characteristics were also considered. The analytical investigation examined the development of existing models for flexure and pure torsion. Interaction diagrams between bending, shear and torsional loads were established from a semi-empirical approach. A damage-based design approach for circular RC columns under combined loads was proposed by decoupling damage index models for flexure and torsion. Experimental and analytical results showed that the progression of damage was amplified by an increase in torsional moment. An increase in the transverse spiral reinforcement ratio delayed the progression of damage and changed the torsional-dominated behavior to flexural-dominated behavior under combined flexural and torsional moments"--Abstract, leaf iii.