1. |
Data Collected |
|
1.1 |
General condition of rocker bearings and surrounding components, including: |
|
1.1.1 |
Longitudinal/lateral shift of rockers. |
|
1.1.2 |
Excessive rotation of rockers. |
|
1.1.3 |
Proper seating and uplifting of rockers and girders. |
|
1.1.4 |
Exposed pintles. |
|
1.1.5 |
Missing nuts. |
|
1.1.6 |
Condition of the anchor bolts. |
|
1.1.7 |
Corrosion and pack rust between rockers and masonry plates; corrosion of other bearing parts. |
|
|
2. |
Onsite Equipment and Personnel Requirements |
|
2.1 |
Equipment: |
|
2.1.1 |
PRE-PL-LO-004, Personal Health and Safety Plan. |
|
2.1.2 |
Ladder, access platform, snooper, bucket truck, man lift, and/or high-reach equipment (if necessary). |
|
2.1.3 |
Wire brush or hand broom. |
|
2.1.4 |
Tape measure. |
|
2.1.5 |
6-ft folding rule. |
|
2.1.6 |
Crack gage. |
|
2.1.7 |
Digital level. |
|
2.1.8 |
Thermometer. |
|
2.1.9 |
Mirror. |
|
2.1.10 |
Plumb bob. |
|
2.1.11 |
Laser measuring device (optional). |
|
2.1.12 |
Hand compass or other angle-measuring device. |
|
2.1.13 |
Temporary marker. |
|
2.1.14 |
Digital camera. |
|
2.1.15 |
Pencil, sketch pad, and clipboard. |
|
2.2 |
Personnel: PRE-PL-LO-005, Personnel Qualifications. |
|
|
3. |
Methodology |
|
3.1 |
Use the segmentation and numbering system for the superstructure (FLD-OP-SC-002, Structure Segmentation and Element Identification System) to identify the bearing being evaluated. |
|
3.2 |
Measuring, recording, and evaluating characteristics of bearings: |
|
3.2.1 |
Record the ambient temperatures above the deck and at the location of the bearing at the time of evaluation. |
|
3.2.2 |
Record if the bearing is a fixed or a moveable (expansion) bearing. |
|
3.2.3 |
Record if the bearing is still in its proper alignment. |
|
3.3 |
Measuring, recording, and evaluating characteristics of rocker assembly: |
|
3.3.1 |
Clean the bearing area by removing any debris or excessive corrosion products. |
|
3.3.2 |
Record the conditions of the rocker and pin, noting if there is any corrosion or loss of section. |
|
3.3.3 |
Does the bearing still rock (still allow movement), or is it “frozen?” |
|
3.3.4 |
Measure the longitudinal and lateral shift and displacement (movements), as well as rotation (tilt angle). |
|
3.3.5 |
Note any exposed, loose, cracked, broken pintles. |
|
3.3.6 |
Look for vertical movement and uplifting of girders under a live load. |
|
3.3.7 |
Use a mirror, if necessary, to examine the bearing area closest to the abutment backwall. |
|
3.4 |
Measuring, recording, and evaluating characteristics of sole plate assembly: |
|
3.4.1 |
Examine the connection of the sole plate to the girder. Record any loss of bond or connection between the sole plate and the girder. |
|
3.4.2 |
Examine the sole plate, and record any cracks, corrosion, or section loss of the sole plate. |
|
3.5 |
Measuring, recording, and evaluating characteristics of the masonry plate: |
|
3.5.1 |
Examine the connection of the masonry plate to the bearing device and the masonry plate to the abutment or pier. Record any loss of connection. |
|
3.5.2 |
Examine the masonry plate and record any cracks, corrosion, or section loss. |
|
3.6 |
Measuring, recording, and evaluating characteristics of anchor bolts: |
|
3.6.1 |
Examine the anchor bolts connecting the masonry plate to the pier or abutment. Record the diameter of the bolts. |
|
3.6.2 |
Record any missing bolts, nuts, or washers. |
|
3.6.3 |
Record any rust or corrosion of the bolts. |
|
3.6.4 |
Examine the concrete around the anchor bolt and record if any part of the main body (shank) of the anchor bolt is exposed. |
|
3.7 |
Measuring, recording, and evaluating characteristics of concrete surface (under and next to the bearing): |
|
3.7.1 |
Check the condition of the concrete surfaces under and next to the bearing and record any defects. |
|
3.7.2 |
Check for spalls, section loss, or cracks in the pier or abutment top surface. |
|
3.8 |
Documenting defects: |
|
3.8.1 |
Take photographs of any defects using FLD-DC-PH-002, Photographing for Documentation Purposes, and create a photo log. |
|
3.8.2 |
Use sketches as needed to document defects and supplement the photographs. |
|
3.9 |
Storing data, documents, and images: |
|
3.9.1 |
FLD-DS-LS-001, Data, Document, and Image Storage—Local, for local storage. |
|
3.9.2 |
FLD-DS-RS-001, Data, Document, and Image Storage—Remote, for remote storage. |
|
3.10 |
Reporting: Transfer all metadata, data, documents, and images to Federal Highway Administration (FHWA), and/or upload all metadata, data, documents, and images into the Long-Term Bridge Performance (LTBP) Bridge Portal. |
|
|
4. |
Data Collection Table |
|
4.1 |
Table: |
|
# |
Field Name |
Data Type |
Accuracy |
Unit |
Field Description |
Row Color |
1 |
State |
Text |
|
|
State Code, e.g., Virginia = VA |
Green |
2 |
NBI structure number |
Text |
|
|
Item 8, Structure Number from NBI Coding Guide |
Green |
3 |
Structure name |
Text |
|
|
Descriptive name for the bridge, e.g., Route 15 SB over I–66 |
Green |
4 |
Protocol name |
Text |
|
|
Title of the protocol |
Green |
5 |
Protocol version |
Text |
Month and year |
|
Month and year the protocol version was published; e.g., May 2015 |
Green |
6 |
Personnel performing data collection activities |
Text |
|
|
First name(s) Last name(s) |
Green |
7 |
Date data were collected |
Text |
Exact date |
|
mm/dd/yyyy |
Green |
8 |
Ambient temperature above deck |
Number |
1 |
°F |
|
Green |
9 |
Bearing number |
Text |
|
|
Evaluate and record data for each individual bearing |
Blue |
10 |
Ambient temperature at bearing location |
Number |
1 |
°F |
|
Yellow |
11 |
Is the bearing fixed or moveable (allows for expansion)? |
Predefined list |
|
|
Fixed or movable |
Yellow |
12 |
If it is a moveable bearing, does it still allow for expansion? |
Predefined list |
|
|
Yes, No, or Not Applicable |
Yellow |
13 |
Is the bearing still in its proper alignment? |
Predefined list |
|
|
Yes or No |
Yellow |
14 |
Condition of the rocker |
Predefined list |
|
|
Indicate no visible defects or document the presence of cracks, corrosion, and/or section loss |
Yellow |
15 |
Condition of the pin |
Text |
|
|
Indicate no visible defects or document the presence of cracks, corrosion, and/or section loss |
Yellow |
16 |
Longitudinal shift/displacement |
Number |
0.125 |
in. |
|
Yellow |
17 |
Lateral shift/displacement |
Number |
0.125 |
in. |
|
Yellow |
18 |
Rotation/tilt |
Number |
1 |
Degrees |
|
Yellow |
19 |
Condition of pintles |
Text |
|
|
Indicate no visible defects, or document any exposed, loose, or cracked pintles. |
Yellow |
20 |
Uplift |
Text |
|
|
Describe any uplift under live load |
Yellow |
21 |
Sole plate connection to girder—Surface bond condition |
Text |
|
|
Indicate no visible defects or document the presence of bond or no bond, movement of sole plate, and other defect (specify under comments) |
Yellow |
22 |
Sole plate condition |
Text |
|
|
Record any corrosion or section loss |
Yellow |
23 |
Masonry plate connection to the abutment or pier |
Text |
|
|
Record any loss of connection |
Yellow |
24 |
Masonry plate condition |
Text |
|
|
Record any corrosion or section loss |
Yellow |
25 |
Diameter of anchor bolts |
Number |
0.125 |
in. |
|
Yellow |
26 |
Condition of the anchor bolts |
Text |
|
|
Record any missing bolts, nuts, washers, or loose bolts; any rust or corrosion of the bolts; or if the anchor bolt is partially exposed |
Yellow |
27 |
Condition of the concrete under and next to the bearing |
Text |
|
|
Indicate no visible defects or document the presence of shear cracks, spalling, on abutment seat or pier cap, and/or other defects (specify under comments) |
Yellow |
28 |
Defect photos |
BLOB |
|
|
Document typical defects with photos |
Yellow |
29 |
Comments |
Text |
|
|
|
Orange |
|
4.2 |
Table Key: |
|
Column Descriptions |
# |
Sequential number of data item |
Field Name |
Data field name |
Data Type |
Type of data, such as text, number, predefined list, binary large object (BLOB), or PDF file |
Accuracy |
Accuracy to which the data are recorded |
Unit |
Unit in which a measurement is taken and recorded |
Field Description |
Commentary on the data or list of items in a predefined list |
Row Color Key |
Green |
Data items only entered once for each protocol for each day the protocol is applied |
Pink |
Logical breakdown of data by elements or defect types (not always used) |
Blue |
Data identifying the element being evaluated or the type of defect being identified |
Yellow |
LTBP data reported individually for each element or defect identified |
Orange |
Comments on the data collection or data entered |
|
|
5. |
Criteria for Data Validation |
|
5.1 |
Compare measurements with measurements from previous inspections of the same structure to make sure that values make sense. |
|
5.2 |
Compare measurements with photo documentation to make sure results shown in photos are consistent with items measured. |
|
5.3 |
If an element’s condition is improved when compared to the condition documented in a previous inspection, check with the State department of transportation to determine if any maintenance, repair, and/or bridge preservation actions have occurred. If so, document these maintenance, repair, and/or bridge preservation actions using appropriate protocols. |
|
|
6. |
Commentary/Background |
|
6.1 |
This protocol provides guidance on evaluating the condition of rocker bearings and for collecting data that help determine if the bearing is functioning as intended. |
|
6.1.1 |
Sole plates are attached to the underside of bridge girders and transfer the force from the bridge girder to the bearing device. |
|
6.1.2 |
The bearing device sits on top of a masonry plate. Masonry plates are attached to piers and abutments and transfer the force from the bearing device to the pier or abutment. |
|
6.1.3 |
Anchor bolts are used to attach the masonry plate to the pier or abutment. The body of an anchor bolt (shank) should not be visible. Only the head of the anchor bolt, a nut, and a washer should be visible. If the body (shank) of the anchor bolt is visible, then the anchor bolts are said to be exposed. |
|
6.1.4 |
The rotation or tilt of the rocker can be determined by measuring the vertical height from the masonry plate to the bottom horizontal edge of the rockers at the front and back sides and the length of the rocker horizontal surface. |
|
6.1.5 |
Measure the longitudinal shift, if any, by measuring the distance from the center line of the rocker to the center line of the masonry plate. |
|
6.1.6 |
Determine the lateral shift by noting any lateral shift of the rockers with respect to keeper plates. |
|
6.1.7 |
A pintle is a pin set into the masonry plate to prevent the rocker from sliding off the masonry plate while allowing rotation to occur. |
|
|
7. |
References |
|
7.1 |
LTBP Protocols: |
|
7.1.1 |
PRE-PL-LO-004, Personal Health and Safety Plan. |
|
7.1.2 |
PRE-PL-LO-005, Personnel Qualifications. |
|
7.1.3 |
FLD-OP-SC-002, Structure Segmentation and Element Identification System. |
|
7.1.4 |
FLD-DC-PH-002, Photographing for Documentation Purposes. |
|
7.1.5 |
FLD-DS-LS-001, Data, Document, and Image Storage—Local. |
|
7.1.6 |
FLD-DS-RS-001, Data, Document, and Image Storage—Remote. |
|
7.2 |
External: |
|
7.2.1 |
FHWA-NHI-12-053, Bridge Inspector’s Reference Manual, Federal Highway Administration, Washington, DC, 2012. |
|