Stress wave inspection of bridge timbers and decking

final report, Research Project Y-3400, Task 10 by Robert J. Hoyle

Publisher: Washington State Dept. of Transportation in cooperation with the U.S. Dept. of Transportation, Federal Highway Administration in [Olympia, Wash.]

Written in English
Published: Pages: 156 Downloads: 945
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  • Wooden bridges -- Inspection.,
  • Stress waves -- Measurement.,
  • Wood -- Testing.,
  • Wooden beams -- Testing.

Edition Notes

Statementby Robert J. Hoyle, Jr. and Paul S. Rutherford (Washington State Transportation Center) ; prepared for Washington State Department of Transportation and in cooperation with U.S. Department of Transportation, Federal Highway Administration.
ContributionsRutherford, Paul S., 1962-, Washington State Transportation Center., Washington (State). Dept. of Transportation., United States. Federal Highway Administration.
The Physical Object
Paginationix, 156 p. :
Number of Pages156
ID Numbers
Open LibraryOL16675990M

A stress wave timer locates bad areas on a bridge by using probes while countless more have timber decking or substructure elements. In a recently completed project, researchers identified new advanced inspection techniques and equipment to help local agency inspectors evaluate their timber bridges. and the inspectors have the knowledge. for timber bridge inspection: u Moisture meter. Timber generally will not decay if the moisture content is less than 20 percent; as the moisture content increases, decay becomes more likely and more serious. Moisture meters effec-tively measure the levels of moisture in timber bridges. u Stress wave timer. This instrument identifies. Australia currently has in service o timber road bridges owned primarily by state and local government authorities. On average, most of these timber bridges have been in service for around 50 years and are in a structural weakened condition due to increasing traffic loads, construction methods, maintenance practices and environmental locations. a wood superstructure. Requirements for the design of wood decks and deck systems are described in the LRFD Specifications, Article A useful reference book, Timber Bridges, Design, Construction, Inspection and Maintenance, is listed at the end of Sections 8 and 9. This.

• The original timber bridge deck was replaced by a steel grid filled w/ concrete (approx 3in) in – The deck replacement resulted in negligible increase in dead load • Eyebars were constructed of heat treated rolled carbon steel bars with forged heads – . Bridge Deck Inspection Using an Infrared Camera (MnDOT, , ) Stress Wave Timer - Timber Bridge Inspection; Resistance Drilling - Timber Bridge Inspection; FHWA EDC Showcase: GRS-IBS Demonstration, Luverne, Minnesota (Minnesota LTAP, , ). Details of the bridge deck structure however can be determined from, the design calculations (undated) prepared by Lt JR Armstrong RNZE, the quantity Survey Sheets, the photographs in the Works Consultancy Services Investigation and Report of 5 the photographs held by Mrs Berryman, and by inspection of the small amount of salvaged. The present study aims to investigate the focused wave impact on coastal bridge deck using REEF3D (Bihs et al., ). Stress wave inspection of bridge timbers and decking. Forest Service;.

Nondestructive Testing FDH is a pioneer in the nondestructive evaluation (NDE) of critical structures. The firm’s research and development of electromagnetic and dispersive wave propagation (DWP) techniques has led to the award of three U.S. patents and multiple proprietary analysis techniques. Project Summary 32 timber bridges inspections completed during Most common type: sawn lumber girder with a sawn lumber deck (plank or nail-laminated) Numerous examples of bridge durability of more than 70 years Use of NDE inspection tools was key for collecting reliable inspection data among the six project teams All field data currently being analyzed for estimation of service life for. Applies to Tabulated Design Values for Extreme Fiber Stress in Bending when members are used as joists, truss chords, rafters, studs, planks, decking or similar members which are in contact or spaced not more than 24″ on centers, are not less than 3 in number and are joined by floor, roof or other load distributing elements adequate to. A sound wave is transmitted through the wood to a receiver; decayed wood slows the stress-wave signal. Stress waves vary by wood species. This approach permits multiple readings (for free-standing readily-accessible timbers or of course, for trees) thus permitting a 2 .

Stress wave inspection of bridge timbers and decking by Robert J. Hoyle Download PDF EPUB FB2

Stress Wave Inspection of Bridge Timbers and Decking. Title. Stress Wave Inspection of Bridge Timbers and Decking. Author. Robert J. Hoyle, Jr., Paul S. Rutherford. Subject. Bridge decks, Bridges, Field tests, Insects, Inspection, Instrumentation, Loss and damage, Manuals, Moisture content, Sound, Stresses, Timber, Waves, Wood preservatives, Wooden bridges.

The use of stress wave velocity to detect wood decay in timber bridges and other structures is limited only by access to the structural members under consideration. It is especially useful on thick timbers or glulam timbers ≥89 mm ( in.) where hammer sounding is not effective.

Note that access to both sides of the member is by: STRESS WAVE INSPECTION OF BRIDGE TIMBERS AND DECKING.

FINAL REPORT. This report is designed to provide information to guide inspectors of wood highway structures in the use of stress wave inspection technology. It explains the methods and instruments used to measure the velocity of stress waves (sound) in wood. Stress Wave Inspection of Bridge Timbers and Decking.

This report is designed to provide information to guide inspectors of wood highway structures in the use of stress wave inspection technology. It explains the methods and instruments used to measure the velocity of stress waves (sound) in wood.

Details Title Bridge Engineering Books – Codes, Manuals, Specification for Bridge Design, Construction and Maintenance – Update Pages + Language Damage Detection and Repair Methods for GFRP Bridge Deck Design Aids of NU I Girders Bridges Standard Plan for Timber Bridge Superstructures.

stress wave theory, or timber bridge maintenance, additional wave inspection of bridge timbers and decking. Pullman, Stress wave inspection of bridge timbers and decking. the bridge. Advanced inspection techniques for timber bridges have been increasing used.

These techniques make use of minimally invasive nondestructive evaluation (NDE) equipment like stress wave timers and resistance microdrills. When used by experienced inspectors, this equipment offers the potential to locate and quantify the.

Stress Grades and Design Properties for Lumber, Round Timber, and Ties David E. Kretschmann, Research General Engineer 7–1 Round timbers, ties, and lumber sawn from a log, regardless of species and size, are quite variable in mechanical proper-ties.


1 GENERAL 1 4. Scope 1 4. Objectives 1 4. Definitions 1 4. 2 STRUCTURE TYPES AND COMPONENTS 3 4. Traditional Timber Girder Bridges 3 4. Sawn Timber Girder Bridges 5 4. Timber Girder (and Stringer) Deck. Abstract. This chapter describes principals of the stress wave applications to timber structures including sonic and ultrasonic techniques.

Correlations between measured physical parameters and material properties are discussed. Bridge Inspection Procedures Conduct a cursory inspection Conduct a hands-on inspection Conduct an in-depth inspection Take moisture readings at areas of dampness, crushing, or any other signs of distress Take stress wave readings along the entire length of the beam and marking high reading locations with chalk.

meter, stress wave tester, and resistograph drill for in-depth inspections and Timber Bridge Analysis and Rating (TBAR) and Mathcad worksheets for load ratings. References [1] AASHTO. The Manual for Bridge Evaluation, American Association of State Highway and Transportation Officials, Washington, DC.

The first 15 chapters cover the following topics, respectively: Timber as a bridge material; Types of timber bridges; Properties of wood and structural wood products; Preservation and protection of timber bridges; Basic timber design concepts for bridges; Loads and forces on timber bridges; Design of beam superstructures; Design of longitudinal.

using a stress wave timer or a Resistograph drill. Nondestructive evaluation, however, is still largely ineffective for detecting incipient decay in timber bridges. Infrared thermography (IR) has one advantage over other nondestructive procedures for early diagnosis of potential wood decay problems.

IR allows inspection of bridge elements from. Laminated timber bridge with timber substructures. This one has spans of 20 feet with a 24 foot roadway and the deck thickness is 12 inches. Deck.” As the width of our roads and bridges increased, a system of staggered butt-joints were used with each butt-joint over a stringer.

This deck. i a tm /afjpam t echnical m anual headquarters no. departments of the army a ir f orce joint p amphlet and the air force n o. w ashington, dc, 6 december bridge inspection, maintenance, and repair paragraph page c hapter 1.

introduction section i. general information. Stress wave timing is an effective method for locating and defining areas of decay in timber bridges. Stress wave propagation in wood is a dynamic process that is directly related to the physical and mechanical properties of wood. In general, stress waves travel faster in sound and high-quality wood than in deteriorated and low-quality wood.

K.A. Malo, in Innovative Bridge Design Handbook, Glulam. Most timber bridges built today use glulam, which is a stack of parallel solid wood lamellas with a thin layer of glue in between, brought together into a single statical element by applied external pressure during the curing of the glue.

Several glulam stacks can be glued together side by side, a process usually referred to. Timber bridges are gaining a resurgence in popularity throughout the United States. There are two basic classifications in timber construction: solid sawn and glued-laminated (glulam).

A solid sawn beam is a section of tree cut to the desired size at a saw mill. Solid sawn multi-beam bridges are the simplest type of timber bridge (see Figure 6.

A bridge floor is the entire length of the bridge from the roadway side of the mudwall or pile cap to the other roadway side of the mudwall or pile cap and the entire width from one coping edge across to the other coping edge.

(The bridge deck is the roadway portion of a bridge, including shoulders.). Advanced Inspection Techniques Other types of advanced inspection techniques are: Coring and Drilling Resistograph Drill Stress Wave Meter Moisture Meter These techniques are beyond the scope of this training course.

General Bridge Inspection Procedures The bridge inspection procedure should be completed by the numbers. Figure Timber truss bridge comprises timber members bolted together. Timber has been used in all parts of bridge structures, and in a wide range of structural types.

Structural form is largely dictated by the size of the timber members that can be cut from the natural timber source, the imagination of the designer and the skill of the builder.

General Bridge Inspection Procedures. Minimum required photographs: 1) Near approach looking at the bridge. 2) Far approach looking at the bridge.

3) Bridge deck and railing. 4) Underside of the deck and beams. 5) Upstream looking downstream at the bridge. 6) Downstream looking upstream at the bridge. 7) Looking upstream from the bridge. Learn Benefits and Constraints of Available Timber Bridge Types.

Learn How to Specify Timber Bridges. Modern Timber Bridges Introduction Inspection and rejection Fixation Field Installation Guidelines Truss can be above or below deck Modern Timber Bridges Pedestrian Bridges Design Codes and Specifications.

Section 1 - Timber bridges - general: Mb: Section 2 - Timber substructures: Mb: Section 3 - Timber truss bridges: Mb: Section 4 - Timber girders, decking and sheeting: Mb: Section 5 - Stress laminated timber systems: Mb: Section 6 - Timber concrete overlay bridges: Kb: Section 7 - Timber concrete composite bridges: Kb.

The components of this NDE system include advanced ultrasonic and stress wave inspection techniques for timber members and vibrational analysis of timber bridges. These techniques will be combined to pinpoint localized damage in individual members and estimate the effects of this damage on the overall capacity of the structural bridge system.

Many of the modern heavy timber buildings are large in area and one story in height. However, the modern multi-story heavy timber building has proved to be entirely practical and satisfactory.

By using stress-graded lumber, either sawn or glued laminated timbers, precise structural design procedures. • Other stress-related cracks - determine the length, size, and location of the crack. Timber Decking The primary locations for timber deck inspection include: • Areas exposed to traffic - examine for wear, weathering, and impact damage.

• Bearing and shear areas where the timber deck contacts the supporting floor system - inspect for. Bridge Materials Topic Timber Introduction Approximately 7% of the bridges listed in the National Bridge Inventory (NBI) are classified as timber bridges.

Another 7% of the total have a timber deck supported by a steel superstructure. Many of these bridges are very old, but the use of timber. Wisconsin DOT Bridge Inspection Quality Control: April Example QC DT Form October Inspector Refresher Training January Timber Bridge Inspection: Resistance Microdrilling Demo: August Timber Bridge Inspection: Stress Wave Timer Demo: August Bridge Deck Inspection: Using An Infrared Camera: August.

comprehensive condition evaluation of decks and asphalt pavements using stress wave scanning. The Vehicle-Mounted Bridge Deck Scanner (BDS) was funded by the NCHRP-IDEA program. The objective of the research project was to develop a Bridge Deck Scanner (BDS) that can be mounted behind any vehicle for comprehensive condition evaluation of.

Davis applied this test method on different concrete structures which include cooling towers, arch bridge, bridge deck, pre-stress box beam bridge, freeways and terra coda clad steel column.

Fig. 21 shows the exposed wall of cooling tower after the IR test and stiffness contour map of pre-stressed box beam bridge.CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): The focus of this research was to develop stress wave NDE techniques for determination of the in-place properties and strength of timber bridge components.

Current inspection procedures for timber bridges is often an art involving visual assessments of the degree of decay and mechanical damage and of the extent to.