strengthening and repairing of existing structures

... span structures has been growing in recent years Material Usage and Condition of Existing Bridges in the U.S REFERENCES “Material Usage and Condition of Existing Bridges in the U.S.,” Portland ... District of Columbia, PR = Puerto Rico 19 Material Usage and Condition of Existing Bridges in the U.S Table A.10 – Number and Percent of Bridges with Main Span Material of RC, PS, Steel and Timber ... District of Columbia, PR = Puerto Rico 20 Material Usage and Condition of Existing Bridges in the U.S Table A.11 – Deck Area and Percent of Bridges with Main Span Material of RC, PS, Steel and Timber...

Ngày tải lên: 20/12/2013, 20:15

... contact surfaces of the structure and seal, galvanic corrosion if the seal plate is of a dissimilar metal to that of the structure itself, or erosion corrosion if abrasive sand and silt particles ... locations on all structures (i.e., trunnion assembly of gates and valves, end posts of lift gates, and end disks of roller gates), lifting connections, and areas where skin plate ribs are attached to ... members and connections and not just view them from a distance Inspectors should use various measuring scales, magnifying glasses, and other hand tools to identify, measure, and locate areas of concerns...

Ngày tải lên: 19/01/2014, 23:20

... hydroxide often forms Deposits of film-forming materials such as oil and grease and sand and silt can also contribute to corrosion by creating crevices and ion concentration cells (2) Corrosion of steel ... 2001 Engineering and Design INSPECTION, EVALUATION AND REPAIR OF HYDRAULIC STEEL STRUCTURES Purpose This manual describes the inspection, evaluation, and repair of hydraulic steel structures, including ... cracking of a component The most important factors governing the fatigue life of structures are the severity of the stress concentration and the stress range of the cyclic loading The fatigue life of...

Ngày tải lên: 19/01/2014, 23:20

... Hydroblasting and Coating of Steel Structures Hyd robIast ing and Coating of Steel Structures Andreas W Momber Privatdozent, Department of Mining, Metallurgy and Earth Sciences, RWTH ... 3.Building, Iron and steel - Cleaning 1.Title 620.1’06 ISBN 185617395X Library of Congress Cataloging-in-PublicationData Momber, Andreas W., 1959 Hydroblasting and coating of steel structures / Andreas ... building sanitation and rehabilitation: concrete hydrodemolition: decontamination and demilitarisation: demolition of technical structures: Hydroblasting and Coating of Steel Structures 3000 2500...

Ngày tải lên: 05/03/2014, 19:20

... Hydroblasting and Coating of Steel Structures Hyd robIast ing and Coating of Steel Structures Andreas W Momber Privatdozent, Department of Mining, Metallurgy and Earth Sciences, RWTH ... 3.Building, Iron and steel - Cleaning 1.Title 620.1’06 ISBN 185617395X Library of Congress Cataloging-in-PublicationData Momber, Andreas W., 1959 Hydroblasting and coating of steel structures / Andreas ... building sanitation and rehabilitation: concrete hydrodemolition: decontamination and demilitarisation: demolition of technical structures: Hydroblasting and Coating of Steel Structures 3000 2500...

Ngày tải lên: 14/03/2014, 17:20

... Hydroblasting and Coating of Steel Structures Hyd robIast ing and Coating of Steel Structures Andreas W Momber Privatdozent, Department of Mining, Metallurgy and Earth Sciences, RWTH ... 3.Building, Iron and steel - Cleaning 1.Title 620.1’06 ISBN 185617395X Library of Congress Cataloging-in-PublicationData Momber, Andreas W., 1959 Hydroblasting and coating of steel structures / Andreas ... building sanitation and rehabilitation: concrete hydrodemolition: decontamination and demilitarisation: demolition of technical structures: Hydroblasting and Coating of Steel Structures 3000 2500...

Ngày tải lên: 22/03/2014, 12:20

... Hydroblasting and Coating of Steel Structures Hyd robIast ing and Coating of Steel Structures Andreas W Momber Privatdozent, Department of Mining, Metallurgy and Earth Sciences, RWTH ... 3.Building, Iron and steel - Cleaning 1.Title 620.1’06 ISBN 185617395X Library of Congress Cataloging-in-PublicationData Momber, Andreas W., 1959 Hydroblasting and coating of steel structures / Andreas ... building sanitation and rehabilitation: concrete hydrodemolition: decontamination and demilitarisation: demolition of technical structures: Hydroblasting and Coating of Steel Structures 3000 2500...

Ngày tải lên: 27/06/2014, 17:20

... 2001 Engineering and Design INSPECTION, EVALUATION AND REPAIR OF HYDRAULIC STEEL STRUCTURES Purpose This manual describes the inspection, evaluation, and repair of hydraulic steel structures, including ... have exhibited fatigue and fracture failures, and many others may be susceptible to fatigue and fracture problems (see c below and Chapter 8) b Types of hydraulic steel structures Lock gates are ... girder at the top and one at the bottom of the leaf The horizontal girders transmit the loads to the miter and quoin at the top of the leaf and into the sill at the bottom of the leaf Horizontally...

Ngày tải lên: 05/08/2014, 11:20

... cracking of a component The most important factors governing the fatigue life of structures are the severity of the stress concentration and the stress range of the cyclic loading The fatigue life of ... cooling of the weld material and HAZ promotes the formation of martensite, which is a brittle phase of steel Preheat and postheat requirements have been adopted (American National Standards Institute/American ... adopted the Sr-N approach for design of welded structures and has published Sr-N curves and guidelines for categorization of welded details for redundant and nonredundant structural members (ANSI/AWS...

Ngày tải lên: 05/08/2014, 11:20

... the lock chamber water level and to opening and closing of gates The number of load cycles is a function of the number of lockages that occurs at the lock The number of load cycles due to gate ... operation of the existing structure, and overstress conditions may 2-14 EM 1110-2-6054 Dec 01 exist Current information, including modern welding practice and fatigue and fracture control in structures, ... the combined effect of the stress range Sr and the stress concentration is reflected in the AASHTO Sr-N curves of Figure 2-1 The fatigue life N is a function of Sr and type of detail (fatigue...

Ngày tải lên: 05/08/2014, 11:20

... contact surfaces of the structure and seal, galvanic corrosion if the seal plate is of a dissimilar metal to that of the structure itself, or erosion corrosion if abrasive sand and silt particles ... locations on all structures (i.e., trunnion assembly of gates and valves, end posts of lift gates, and end disks of roller gates), lifting connections, and areas where skin plate ribs are attached to ... members and connections and not just view them from a distance Inspectors should use various measuring scales, magnifying glasses, and other hand tools to identify, measure, and locate areas of concerns...

Ngày tải lên: 05/08/2014, 11:20

... detectability and reliability of the inspection method, inspector qualifications, and economic considerations A summary of NDT methods that describes advantages and disadvantages of each is provided ... components of the structure (5) The inspector should complete a report following the actual inspection The report should include the identification and location of inspected structures, date and time of ... inspection, the type and extent of the deformation must be described accurately and in detail so that an assessment of the effect of the damage can be made The location of the damaged member...

Ngày tải lên: 05/08/2014, 11:20

... effect of bead configuration, and macrodefects of welded joints The quality of welds can be evaluated as a function of ductility to resist cracking during bending The top and bottom surfaces of a ... joint, and one of the cut side surfaces becomes the tension side of the bent specimen For all types of bend tests, face, root, and side, the specimen is tested at ambient temperature, and deformation ... 0.2 percent offset yield strength and KIc is the plane strain fracture toughness of the material at the desired test temperature and loading rate The initial selection of a size of specimen may...

Ngày tải lên: 05/08/2014, 11:20

... in Figures 6-8 through 6-16 (Barsom and Rolfe 1987) Barsom and Rolfe and Tada, Paris, and Irwin (1985) contain compilations of solutions for a wide variety of configurations c After the stress-intensity ... permission of PrenticeHall, Inc., Englewood Cliffs, NJ) where KT = theoretical stress concentration factor, aN = half of the long dimension of the ellipse, b = half of the short dimension of the ... copies of the standard can be obtained by post from BSI Publications, Linford Wood, Milton Keynes, MK14 6LE) Figure 6-7 Interaction of discontinuities with surfaces (Extracts from British Standards...

Ngày tải lên: 05/08/2014, 11:20

... Relation between dimensions of a discontinuity and the parameter ā for embedded discontinuities (Extracts from British Standards Institution 1980 Complete copies of the standard can be obtained by ... Association of State Highway and Transportation Officials 1996; American Institute of Steel Construction 1994; EM 1110-2-2105) (5) Integrate the crack growth rate expression (i.e., Equations 6-8 and ... characterize the fatigue strength and life of the riveted member detail (c) When Sre ≥ 68.9 MPa (10 ksi), use Category D and Sre to characterize the fatigue strength and life of the riveted member detail...

Ngày tải lên: 05/08/2014, 11:20

... structural integrity of the spillway gate must be evaluated (a) Since an evaluation of the local buckling of the strut arms was conducted when it was first observed and the amount of buckling on the ... and geometry of detail are known and the stress level and material fracture toughness have been estimated, the crack can be evaluated for fracture by calculating the stress intensity factor and ... factor of safety (FS), KIf , is given by  a FS   K If = 1.12σ π a FS • k   b  (7-7) where a = crack size k = function of a and b b = half-width of the plate (Tabulated values for k and stress...

Ngày tải lên: 05/08/2014, 11:20

... Hydraulic Steel Structures Steel standards for the period when many hydraulic steel structures were constructed are of interest from both a structural evaluation and a repair and maintenance standpoint ... fracture and fatigue analysis of this example consists of three propagation steps (1) The first step is to analyze the crack propagation of a hemispheric surface crack having an initial radius of 1.6 ... yield point of 310 MPa (45 ksi) and tensile strength of 552 to 655 MPa (80 to 95 ksi)) through a high level of carbon (0.44 percent maximum) It also had limits on its phosphorus and sulfur contents...

Ngày tải lên: 05/08/2014, 11:20

... possibility of poor quality welds Moisture, paint, and other foreign material that can produce weld defects and cracking are often present Welding residual stresses and degradation of material ... grinding, peening, remelting, and hole drilling The appropriate repair method for a given situation is dependent on the size and location of the crack and the type of detail at which the cracking ... range (algebraic sum of the tensile and compressive stress), and the crack size a (see Equation 6-1) includes the extent of the hole Equation 8-1 is valid for structural steel and provides reasonable...

Ngày tải lên: 05/08/2014, 11:20

... type of connection (intersection of bracing members, diaphragms, and girders) is a very common occurrence on lift gates, miter gates, tainter gates, and bridges Flanges of bracing members and ... Cause of cracking The crack was located in the tension flange of the vertical girder at the intersection of the bracket plate and the flange plate The weld that joins the bracket plate and flange ... Cracked girder, diaphragm, and bracing in a lift gate (2) Cause of cracking The location and orientation of cracks indicate that cracking initiated at weld terminations and weld intersections The...

Ngày tải lên: 05/08/2014, 11:20

... New Construction and Maintenance CWGS 05036 Metallizing: Hydraulic Structures CWGS 09940 Painting: Hydraulic Structures American Association of State Highway and Transportation Officials 1996 American ... Department of Transportation 1988 Pennsylvania Department of Transportation 1988 “Guidelines for Fatigue and Fracture Safety Inspection of Bridges,” Commonwealth of Pennsylvania, Department of Transportation, ... increased brittleness and likelihood of embedded discontinuities The use of uncoped stiffeners should always be avoided; however, there are many such cases in existing USACE structures A similar...

Ngày tải lên: 05/08/2014, 11:20