[PDF] High Strength Stainless Steels For Corrosion Mitigation In Prestressed Concrete eBook

Author : Robert David Moser
Publisher :
Page : pages
File Size : 17,99 MB
Release : 2011
Category : Corrosion and anti-corrosives
ISBN :

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The use of stainless steel alloys in reinforced concrete structures has shown great success in mitigating corrosion in even the most severe of exposures. However, the use of high-strength stainless steels (HSSSs) for corrosion mitigation in prestressed concrete (PSC) structures has received limited attention. To address these deficiencies in knowledge, an experimental study was conducted to investigate the feasibility of using HSSSs for corrosion mitigation in PSC. The study examined mechanical behavior, corrosion resistance, and techniques for the production of HSSS prestressing strands. Stainless steel grades 304, 316, 2101, 2205, 2304, and 17-7 along with a 1080 prestressing steel control were included in the study. Tensile strengths of 1250 to 1550 MPa (181 to 225 ksi) were achieved in the cold-drawn HSSSs. 1000 hr stress relaxation of all candidate HSSSs was predicted to be between 6 and 8 % based on the results of 200 hr tests conducted at 70 % of the ultimate tensile strength. Residual stresses due to the cold drawing had a significant influence on stress vs. strain behavior and stress relaxation. Electrochemical corrosion testing found that in solutions simulating alkaline concrete, all HSSSs showed exceptional corrosion resistance at chloride (Cl- ) concentrations from zero to 0.25 M. However, when exposed to solutions simulating carbonated concrete, corrosion resistance was reduced and the only HSSSs with acceptable corrosion resistance were duplex grades 2205 and 2304, with 2205 resistant to corrosion initiation at Cl- concentrations up to 1.0 M (twice that in seawater). Based on these results, duplex grades 2205 and 2304 were identified as optimal HSSSs and were included in additional studies which found that: (1) 2304 is susceptible to corrosion when tested in a stranded geometry, (2) 2205 and 2304 are not susceptible to stress corrosion cracking, and (3) 2205 and 2304 are susceptible to hydrogen embrittlement. Efforts focused on the production of 2205 and 2304 prestressing strands showed that they could be produced as strands using existing ASTM A416 prestressing strand production facilities. Due to the ferromagnetic properties of 2205 and 2304, a low-relaxation heat treatment was found to be a viable option to reduce stress relaxation and improve mechanical properties. The overall conclusion of the study was that HSSSs, especially duplex grades 2205 and 2304, show excellent promise to mitigate corrosion if utilized as prestressing reinforcement in PSC structures exposed to severe marine environments.

Author : Daniel Philip Schuetz
Publisher :
Page : pages
File Size : 23,7 MB
Release : 2013
Category : Building materials
ISBN :

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Bridges and other coastal structures in Georgia and throughout the Southeast are deteriorating prematurely due to corrosion. Numerous corrosion initiated failures have occurred in precast prestressed concrete (PSC) piles and reinforced concrete (RC) pile caps, leading to the costly repair and replacement of either the entire bridge or the affected members. With the Federal Highway Administration's goal of a 100-year bridge service life and recent legislative action such as the Bridge Life Extension Act, new emphasis has been placed on the development and implementation of new corrosion mitigation techniques. This thesis involves the mechanical testing, and proposed future test program of high-strength stainless steel (HSSS) prestressing strand to be used in prestressed marine bridge piles. The metallurgy for two types of HSSS strand was selected from a previous study of the corrosion resistance, mechanical properties, and feasibility of 6 candidate HSSS drawn wire samples. Duplex stainless steel (DSS) grades 2205 and 2304 were selected for production of 7-wire 1/2" diameter prestressing strand. DSS wire rod was drawn, stranded, and heat-treated using the same production methods and equipment as used for standard of practice, high carbon prestressing strand. The production process was documented to analyze the problems facing this production method and suggest improvement and optimization. After production, the strands were subjected to a series of mechanical tests. Tension testing was performed to provide a stress-strain curve for the strands and related mechanical properties. Wire samples were also taken at varying points in the drawing process to give more information about the work hardening of the stainless steels. Stress relaxation testing was performed on both strand and wire samples to assess the overall losses and to provide comparisons between strand and wire test results as well as drawn wires before and after heat-treatment. An experimental program for future study was designed to assess the HSSS prestressing strand behavior in precast piles. This testing involves assessment of pile driving performance, pile flexural and shear behavior, strand transfer and development length, long-term prestressing force losses, and material durability.

Author : Luca Bertolini
Publisher : John Wiley & Sons
Page : 389 pages
File Size : 10,94 MB
Release : 2013-02-26
Category : Technology & Engineering
ISBN : 3527651713

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Steel-reinforced concrete is used ubiquitously as a building material due to its unique combination of the high compressive strength of concrete and the high tensile strength of steel. Therefore, reinforced concrete is an ideal composite material that is used for a wide range of applications in structural engineering such as buildings, bridges, tunnels, harbor quays, foundations, tanks and pipes. To ensure durability of these structures, however, measures must be taken to prevent, diagnose and, if necessary, repair damage to the material especially due to corrosion of the steel reinforcement. The book examines the different aspects of corrosion of steel in concrete, starting from basic and essential mechanisms of the phenomenon, moving up to practical consequences for designers, contractors and owners both for new and existing reinforced and prestressed concrete structures. It covers general aspects of corrosion and protection of reinforcement, forms of attack in the presence of carbonation and chlorides, problems of hydrogen embrittlement as well as techniques of diagnosis, monitoring and repair. This second edition updates the contents with recent findings on the different topics considered and bibliographic references, with particular attention to recent European standards. This book is a self-contained treatment for civil and construction engineers, material scientists, advanced students and architects concerned with the design and maintenance of reinforced concrete structures. Readers will benefit from the knowledge, tools, and methods needed to understand corrosion in reinforced concrete and how to prevent it or keep it within acceptable limits.

Author : fib Fédération internationale du béton
Publisher : fib Fédération internationale du béton
Page : 24 pages
File Size : 30,10 MB
Release : 2001-01-01
Category : Technology & Engineering
ISBN : 9782883940512

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Without doubt, active corrosion protection of prestressing steels by cement grout can be one of the most economic and durable solutions, if properly executed. Numerous other corrosion protection systems which fulfill requirements such as controllability and exchangeability are available. This state-of-the-art report, prepared by a task group and approved by fib Commission 9 Reinforcing and prestressing materials and systems, concentrates exclusively on factory applied corrosion protection that can be produced in controlled processes which should assure a better quality than corrosion protection applied on site. The report is addressed to designers and installers (executing persons) attempting to inform them about the various possibilities for industrially applied corrosion protection and to provide the necessary knowledge for their application.

Author : Joseph Rogelio Fernandez
Publisher :
Page : pages
File Size : 42,6 MB
Release : 2011
Category :
ISBN :

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Results of Phase 1 showed that for exposure at 135oC (275oF) cracking of alloys 316 L and 2205 occurred after 1 hour while XM29 experience cracking after 24 hours. At 90oC (194oF) alloy 316L cracked after 4 hours; XM29 did not crack after 96 hours while 2205 did crack after 96 hours. The results were interpreted with an Arrhenius relationship between time to cracking and test temperature to extrapolate toward the anticipated service regime. Results of Phase 2 showed that SCC was less likely to initiate in high pH conditions than in low pH conditions at typical marine environment temperatures and chloride concentration. In these limited tests the SCC performance of XM29 was better relative to that of the other two alloys.

Author : A. F. Hoenie
Publisher :
Page : 48 pages
File Size : 14,26 MB
Release : 1966
Category : Martensitic stainless steel
ISBN :

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This report presents information on the physical metallurgy, chemical composition, mechanical and physical properties, corrosion resistance, fabrication, and cleaning of several of the newer high-strength stainless steels. The alloys covered include one semiaustenitic precipitation-hardenable stainless steel, PH14-8Mo, and the following martensitic precipitation- hardenable stainless steels: PH13-8Mo, 15-5PH, Custom 455, AM-363, AM-362, and AFC-77. Also included is 17-4PH as a sheet and strip product.