《TRAILBRIDGEINSPECTION.ppt》由会员分享，可在线阅读，更多相关《TRAILBRIDGEINSPECTION.ppt（53页珍藏版）》请在三一文库上搜索。
1、TRAIL BRIDGE INSPECTION BRIDGE INSPECTION PROCEDURES,Objectives:,Learn the different inspection methods Learn a standard procedure to conduct routine bridge inspection Learn what to look for during an inspection,Bridges Inspection Methods,There are three basic methods used to inspect a timber bridge
2、. They include: Visual Physical Advanced inspection techniques,Visual Inspections,For timber members, visual inspections reveal areas that need further investigation such as checks, splits, shakes, fungus decay, deflection, or loose fasteners.,Types of Visual Inspections,Cursory Inspection Involves
3、reviewing the previous inspection report and visually examining the members Involves a visual assessment to identify obvious defects “Hands-on” Inspection. Requires the inspector to visually assess all defective timber surfaces at a distance no further than an arms length Timber surfaces are given c
4、lose visual attention to quantify and qualify any defects.,Physical Examination,Once the defects are identified visually Physical procedures are then used to find out the extent of the deterioration or decay The basic methods for physical examination are: Pick Test Sounding,Pick Test,Probing with a
5、pointed tool such as an awl will locate decay near the wood surface. Decay will be evidenced by excessive softness or lack of resistance to the probe penetration and the breakage pattern of the splinters. A brash break indicates decayed wood, whereas a crisp splintered break with the splinter hingin
6、g from one end indicates sound wood.,Pick Test,Decayed wood breaks abruptly across grain without splintering.,Sound wood pries out as long splinters.,Sounding,Sounding the surface by striking it with a hammer is one of the oldest and most commonly used inspection methods. Although sounding is widely
7、 used, interpretation is VERY subjective. Soundings are based on the tonal quality of the ensuing sounds and the rebound of the hammer Practical experience has shown that sounding is only useful for members less than 4 inches thick.,Sounding,Interpreting Soundings: Sound timber gives a crisp sound.
8、Defective timber gives a dull sound. Loose hardware will vibrate. Note: A 2 inch thick shell of competent wood is sufficient to mask any interior rot.,Advanced Inspection Techniques,Other types of advanced inspection techniques are: Coring and Drilling Resistograph Drill Stress Wave Meter Moisture M
9、eter These techniques are beyond the scope of this training course.,General Bridge Inspection Procedures,The bridge inspection procedure should be completed by the numbers. Which means the bridge is inspected in a methodical way from either top to bottom or bottom to top. It is important to document
10、 the inspection.,General Bridge Inspection Procedures,Documentation should include: An inspection report and notes And lots of photographs Photographs should be a minimum of 10 pictures with additional pictures of problem areas.,General Bridge Inspection Procedures,Minimum required photographs: Near
11、 approach looking at the bridge Far approach looking at the bridge Bridge deck and railing Underside of the deck and beams Upstream looking downstream at the bridge Downstream looking upstream at the bridge Looking upstream from the bridge Looking downstream from the bridge Near side substructure Fa
12、r side substructure,Near and far approaches looking at the bridge,Bridge Deck and Railing,Underside of Deck and Beams,Looking upstream and downstream from the bridge deck,Looking upstream and downstream at the bridge,Looking at right and left abutments,Additional Photos,Anything that needs to be not
13、ed or watched.,Starting an Inspection,First conduct a cursory visual inspection of the entire bridge looking for indications of problems.,Cursory Visual Inspection,Look for: Sagging or twisted beams Hanging or broken beams Pounding water Settlement,Next, conduct a hands-on visual inspection of the b
14、ridge parts taking into account any indications of problem found during the cursory inspection. During the hands-on visual inspection, the inspector should look for signs of deterioration or decay that will require a physical examination.,Where to look for decay?,Where to look for decay?,Around Chec
15、ks Around Splits Around Shakes Around Cracks Around Fasteners Areas in contact with soil Areas where debris and water collect,Conduct the inspection BY THE NUMBERS Start at the top of the bridge and work your way down the load paths. This will help you from missing any parts of the structure.,One In
16、spection order could be: Railings/curbs Decking (Planks) Superstructure (Beams, Stringers) Substructure (Abutments, Sills) Channel Approaches Signage,General Bridge Inspection Procedures,1) Inspection of railings/curbing Things to looking for? Missing rails, posts, curbs or hardware Broken rails, po
17、sts or curbs Deteriorated (rotten) rails, posts or curbs,1) Inspection of railings/curbing,Missing rails, posts, curbs or hardware,1) Inspection of railings/curbing,Broken rails, posts or curbs,1) Inspection of railings/curbing,Deteriorated (rotten) rails, posts or curbs,General Bridge Inspection Pr
18、ocedures,2) Inspection of decking Things to looking for? Missing planks or hardware Broken planks or hardware Deteriorated (rotten) planks Wear of the deck Debris on deck,2) Inspection of decking,Missing planks or hardware,2) Inspection of decking,Broken planks or hardware,2) Inspection of decking,D
19、eteriorated (rotten) planks,2) Inspection of decking,Wear of the deck,2) Inspection of decking,Debris on deck,General Bridge Inspection Procedures,3) Inspection of superstructure Things to looking for? Sagging beams Broken or cracked beams Missing hardware Deteriorated (rotten) beams Impact damage o
20、f beams from floating debris or ice,3) Inspection of superstructure,Sagging beams,3) Inspection of superstructure,Broken or cracked beams,3) Inspection of superstructure,Deteriorated (rotten) beams,3) Inspection of superstructure,Impact damage of beams from floating debris or ice,General Bridge Insp
21、ection Procedures,4) Inspection of substructure Things to looking for? Settlement of the substructure Missing substructure or hardware Deteriorated (rotten) substructure Damage of substructure from floating debris or ice Scour damage,4) Inspection of substructure,Settlement of the substructure,4) In
22、spection of substructure,Deteriorated (rotten) substructure,4) Inspection of substructure,Scour damage,4) Inspection of substructure,Other things to look for: Missing substructure or hardware Damage of substructure from floating debris or ice,General Bridge Inspection Procedures,5) Inspection of the
23、 Channel Things to looking for? Degrading of the stream (down cutting) Aggrading of the stream (deposits) Scour of the banks Loss of bank protection Floating debris or Ice damage,General Bridge Inspection Procedures,6) Inspection of approaches Things to looking for? Approach material washed away Slu
24、mping of the approaches at the backwall Unraveling at the edges of trail Potholes,General Bridge Inspection Procedures,7) Inspection of signs Things to looking for? Broken or damaged signs and posts Dont forget to count the bullet holes Missing fastners Missing signs/object markers for ATV and Snowm
25、obile bridges,References,FHWA Bridge Inspection Reference Manual FHWA Field Manual for Timber Bridge Inspection, Draft FPL Controlling Decay in Water Front Structures FPL Timber Bridges Design, Construction, Inspection and Maintenance FPL Wood Handbook FPS Wood and Timber Condition Assessment Manual R6 Trail Bridge Inspection R10 Training PowerPoints,End Bridge Inspection Procedures,