bridge truss constructions

Mabey Inc.6770 Dorsey RoadElkridge, Maryland 21075T: 410-379-2800F: 410-379-2801mabey.com

1

CONTENTS

INTRODUCTION 2 Basic Bridge Components 2 BRIDGE DIMENSIONS 3 BRIDGE TRUSS CONSTRUCTIONS Construction Diagrams 4 Key to Abbreviations 5 BRIDGE PROPERTIES Bending Moment & Shear Capacities 6 BRIDGE WEIGHTS Table of Bridge Weights 7 LOAD SPECIFICATIONS AASHTO HS20/HS25 Design Loading 8 Truck Loading 8 Lane Loading 8 SPAN CONSTRUCTION TABLES AASHTO HS20 Design Loading 9 AASHTO HS20 Design Loading with 2” Asphalt Surfacing 10 AASHTO HS25 Design Loading 11 AASHTO HS20 Design Loading with 2” Asphalt Surfacing 12 ALLOWABLE LOADS ON TRANSOMS AND DECK SYSTEMS General Notes 13 Transoms for Single Lane Roadways – Maximum Axle Loads 13 Transoms for Two Lane Roadways – Maximum Axle Loads 13 Steel Decking – Maximum Wheel Loads 13 BRIDGE FOUNDATIONS Notes Pertaining to the Bridge Abutment Diagrams 14 Typical Foundation Layout 15 MULTIPLE SPAN BRIDGES Top Pin Out 16 Span Junction Equipment 16 Continuous 16 Separate Bearings 16

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INTRODUCTION The Mabey Universal Panel Bridge System has been developed to enable a large range of bridge spans, with various roadway widths and in diverse span configurations, to be built from a standard range of stock components. Mabey Universal bridges can be easily transported to site using standard trucks. They are also very quick and easy to erect and install. The use of galvanized high strength steel ensures long term low maintenance structures. The constraints of space in this publication prohibit dealing with many aspects of the system, including:

• Standard panels and chords • Footwalks – both internal and external (cantilevered) • Special deck systems (incl. timber decked bridges) • Pedestrian Bridges – both through truss and box truss • Deck Bridges • Bridge assembly details • Bridge installation methods • Inspection and maintenance procedures

For information on these features, bridge constructions required for other highway or non-standard loadings, or any other questions about aspects of the bridge system, please contact Mabey Bridge & Shore, Inc.

BASIC BRIDGE COMPONENTS

3

BRIDGE DIMENSIONS

Clear between Trusses = Dim. B - 914"

17'-1

13 16"

Dou

ble

Stor

ey R

einf

orce

d

5"

2'-434"

16'-3

13 16"

Dou

ble

Stor

ey

B

A

C

8'-1

115 16"

Dou

ble

Stor

ey R

einf

orce

d

8'-1

15 16"

Sing

le S

tore

y

2'-434" 5"

D

ROADWAY WIDTHS

DIMENSIONS

13.8ft

24.1ft

30ft

34.4ft

A 13’-93/8” 24’-13/8” 30’-011/16” 34’-53/8” B 16’-3” 27’-0” 32’-31/4” 38’-07/8” C 22’-55/8” 32’-61/2” 37’-57/8” 43’-73/8” D 2’-25/8” 2’-101/2” 2’-107/8” 3’-13/4”

Notes:

1. Dimensions are subject to manufacturing tolerances. 2. Dimensions are to steel components, please add additional height for any surfacing required.

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BRIDGE TRUSS CONSTRUCTIONS

CONSTRUCTION DIAGRAMS

TDHR3H

TSHR3H

TDH TDHR2H

DDHR1HDDH DDHR2H

TSH TSHR2H

DSHR1HDSH

SSH

DSHR2H

SSHRH

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BRIDGE TRUSS CONSTRUCTIONS

KEY TO ABBREVIATIONS

CODE

DESCRIPTION OF TRUSS CONSTRUCTION

SSH

SSHRH

DSH

DSHR1H

DSHR2H

TSH

TSHR2H

TSHR3H

DDH

DDHR1H

DDHR2H

TDH

TDHR2H

TDHR3H

H

*

SINGLE SINGLE: each truss has a single panel line in single story.

SINGLE SINGLE REINFORCED: each truss has a single panel line in single story, with a reinforcing chord attached to both the bottom and the top of the panel. *

DOUBLE SINGLE: each truss has two panel lines in single story.

DOUBLE SINGLE REINFORCED ONE: each truss has two panel lines in a single story, with a reinforcing chord attached to both the bottom and the top of the inner panel of the truss only. *

DOUBLE SINGLE REINFORCED TWO: each truss has two panel lines in single story, with a reinforcing chord attached to both the bottom and the top of all panels. *

TRIPLE SINGLE: each truss has three panel lines in single story.

TRIPLE SINGLE REINFORCED TWO: each truss has three panel lines in single story, with a reinforcing chord attached to both the bottom and the top of the inner and outer panels of the truss only. *

TRIPLE SINGLE REINFORCED THREE: each truss has three panel lines in single story, with a reinforcing chord attached to both the bottom and the top of all panels. *

DOUBLE DOUBLE: each truss has two panel lines in double story.

DOUBLE DOUBLE REINFORCED ONE: each truss has two panel lines in double story, with a reinforcing chord attached to both the bottom and the top of the inner panel of the truss only. *

DOUBLE DOUBLE REINFORCED TWO: each truss has two panel lines in double story, with a reinforcing chord attached to both the bottom and the top of all panels. *

TRIPLE DOUBLE: each truss has three panel lines in double story.

TRIPLE DOUBLE REINFORCED TWO: each truss has three panel lines in double story, with a reinforcing chord attached to both the bottom and the top of the inner and outer panels of the truss only. *

TRIPLE DOUBLE REINFORCED THREE: each truss has three panel lines in double story, with a reinforcing chord attached to both the bottom and the top of all panels. *

The letter “H” is used after the panel configuration or the reinforcing chord configuration to signify that super panels or super chords are to be used to form the bridge trusses, instead of standard panels or standard chords, for example: “SSR” signifies that standard panels and standard chords are to be used in the bridge truss.

Note that the final bay at each end of a span is always of unreinforced construction.

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BRIDGE PROPERTIES

BENDING MOMENT AND SHEAR CAPACITIES

SHEAR CAPACITY (kips)

TRUSS CONSTRUCTION

MOMENT CAPACITY (k-ft) STANDARD SHEAR HIGH SHEAR

SSH SSHRH

DSH DSHR1H DSHR2H

TSH TSHR2H TSHR3H

DDH DDHR1H DDHR2H

TDH TDHR2H TDHR3H

3615 7155

7873 12233 16594

11322 19671 23849

14458 21570 28712

21680 35911 43045

156 156

282 211 282

422 353 422

524 379 524

786 654 786

223 223

403 302 403

604 504 604

564 408 564

846 706 846

Notes:

1. The Moment and Shear properties tabulated above are total bridge capacities (two trusses). 2. These capacities incorporate a minimum factor of safety against failure of 1.7. 3. The two columns of Shear capacities listed refer to the versions of shear panels available for

Mabey Universal Super Panel Bridges, which are as follows: Standard Shear Super Panel having a capacity of 77 kips per panel. High Shear Super Panel having a capacity of 110 kips per panel.

4. The Moment capacities above for all constructions (except SSH & SSHRH) assume the use of horizontal bracing frames. Bracing frames may be omitted on the bridge in some instances, but users should contact Mabey Bridge & Shore, Inc. engineers for further information.

5. All double story constructions must have end posts at abutments.

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BRIDGE WEIGHTS

TABLE OF BRIDGE WEIGHTS

13.8ft r/w 24.1ft r/w 30ft r/w 34.4ft r/w BRIDGE

TRUSS CONSTR-UCTION

FULLY DECKED

NO DECK

FULLY DECKED

NO DECK

FULLY DECKED

NO DECK

FULLY DECKED

NO DECK

SSH SSHRH

DSH DSHR1H DSHR2H

TSH TSHR2H TSHR3H

DDH DDHR1H DDHR2H

TDH TDHR2H TDHR3H

10.23 12.27

13.94 15.90 17.86

16.95 20.87 22.83

20.27 22.23 24.19

26.32 30.24 32.19

5.37 7.40

9.07 11.03 12.99

12.08 16.00 17.96

15.41 17.37 19.33

21.45 25.37 27.33

17.56 19.59

21.26 23.22 25.18

24.28 28.19 30.15

27.60 29.56 31.52

33.64 37.56 39.52

9.23 11.26

12.93 14.89 16.85

15.94 19.86 21.82

19.27 21.22 23.18

25.31 29.23 31.19

21.28 23.31

24.98 26.94 28.90

28.00 31.91 33.87

31.32 33.28 35.24

37.36 41.28 43.24

10.66 12.69

14.36 16.32 18.28

17.37 21.29 23.25

20.70 22.65 24.61

26.74 30.66 32.62

24.89 26.92

28.60 30.55 32.51

31.61 35.53 37.48

34.93 36.89 38.85

40.97 44.89 46.85

13.09 15.12

16.80 18.75 20.71

19.81 23.73 25.68

23.13 25.09 27.05

29.17 33.09 35.05

Notes: 1. The weights tabulated above are in kips per 14.76ft long bay and are based upon the theoretical

component weights with an allowance of 2.5% for galvanizing and finishes. 2. The “fully decked” weights are with all steel deck components fitted, and the “no deck”

weights are with neither steel deck units nor curbs fitted. 3. No surfacing weights are included in the fully decked weights. 4. The final bay at either end of a bridge is always unreinforced, even when the bridge is of a

reinforced truss construction. 5. To calculate the total weight of the bridge, the designer must include additional weight for End

of Bridge Components and additional weights for High Shear Panels. See Mabey Bridge & Shore, Inc. engineers for further information.

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LOAD SPECIFICATIONS

(AS APPLICABLE TO SIMPLY SUPPORTED BRIDGE TRUSSES)

AASHTO HS20/HS25 DESIGN LOADING HS20 design loading, according to the Standard Specification for Highway Bridges adopted by the American Association of State Highway and Transportation Officials (AASHTO), comprises two alternate forms of highway loading, Truck Loads and Lane Loads. Both of these loads should be analyzed for the span under consideration, and the worst effects of either applied to the bridge structure. HS25 is obtained by increasing the HS20 loads by 25%. TRUCK LOADING The truck loading consists of a three axled truck with axle loads and longitudinal and transverse geometry as shown in the diagrams below. HS20-44 Truck

32,000 lbs

14 ft

8,000 lbs

14 ft

32,000 lbs

(WheelCenters)

6 ft

10 ft(Design Lane)

LANE LOADING The lane loading consists of a uniform load with a single concentrated load, so placed to produce the maximum stress. HS20-44 loading Uniform Load 640lbs per linear foot of load lane Concentrated Load - 18,000lbs for Moment

- 26,000lbs for Shear Notes:

1. Both the Truck Loads and the Lane Loads occupy a width of 10 feet. These loads are placed in a 12-foot wide design traffic lane, spaced across the entire bridge roadway width measured between curbs.

2. Both the Truck Loads and the Lane Loads are increased for impact, according to the formula: I = 50/(L+125) I = impact fraction (maximum 30%) L = span of the bridge in feet.

3. The above loadings are for simply supported spans only, for continuous structures please refer to Mabey Bridge & Shore, Inc. engineers.

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SPAN CONSTRUCTION TABLES

AASHTO HS20 LOADING

BRIDGE SPAN ROADWAY WIDTHS FEET BAYS 13.8ft

Single lane 24.1ft 2 lane

30ft 2 lane

34.4ft 3 lane

59 4 SSH DSH DSH DSH 73 5 SSH DSH DSH DSH+ 88 6 SSH DSH DSH DSH+ 103 7 SSHRH DSH DSHR1H++ DSHR2H+ 118 8 SSHRH DSHR1H+ DSHR1H++ DSHR2H+ 132 9 SSHRH DSHR1H++ DSHR2H+ DSHR2H++ 147 10 SSHRH DSHR1H++ DSHR2H+ DSHR2H++ 162 11 SSHRH+ DSHR2H+ DSHR2H++ DSHR2H++ 177 12 DSHR1H DSHR2H++ DSHR2H++ TSHR2H++ 192 13 DSHR1H+ TSHR2H+ TSHR3H+ TSHR3H++ 206 14 DSHR1H+ TSHR3H TSHR3H+ DDHR2H+ 221 15 DSHR2H TSHR3H+ DDHR2H TDHR2H 236 16 DDHR1H DDHR2H TDHR2H TDHR3H 251 17 DDHR1H TDHR2H TDHR3H TDHR3H 265 18 DDHR2H TDHR3H - -

Notes:

1. The number of “+” after a construction indicates the number of bays at each end of the bridge span that are to be constructed using High Shear Super Panels as follows: + = 1 bay of High Shear Panels required at each end of the span ++ = 2 bays of High Shear Panels required at each end of the span

2. Truss constructions are based on full scale load test results with a minimum Factor of Safety of 1.7. Some codes may require different factors of safety. If a different factor of safety is required, span constructions may change.

3. No consideration has been made for Live Load Deflection limits. 4. Constructions are chosen for a minimum fatigue life of 100,000 cycles of loading. Where a

longer fatigue life is required, the advice of Mabey Bridge & Shore, Inc. engineers should be sought.

5. A maximum span to depth ratio of 25:1 has been assumed. 6. The constructions tabulated above assume the use of standard deck systems which are adequate

for the specified loading. If a heavy deck system is required (see page 13), the tabulated constructions may not be adequate. Contact Mabey Bridge & Shore, Inc. engineers for advice.

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AASHTO HS20 LOADING with 2” ASPHALT SURFACING



30ft 2 lane

34.4ft 3 lane

59 4 SSH DSH DSH DSH 73 5 SSH DSH DSH DSH+ 88 6 SSH DSH DSH DSH+ 103 7 SSHRH DSH DSHR1H++ DSHR2H+ 118 8 SSHRH DSHR1H++ DSHR2H+ DSHR2H++ 132 9 SSHRH+ DSHR1H++ DSHR2H++ DSHR2H++ 147 10 SSHRH+ DSHR2H+ DSHR2H++ TSHR2H++ 162 11 DSHR1H DSHR2H++ TSHR2H++ TSHR2H++ 177 12 DSHR1H+ TSHR2H+ TSHR3H+ TSHR3H++ 192 13 DSHR1H+ TSHR3H+ DDHR2H TDHR2H 206 14 DSHR2H DDHR2H DDHR2H+ TDHR2H 221 15 DSHR2H+ DDHR2H TDHR2H TDHR3H 236 16 DDHR1H TDHR2H TDHR3H - 251 17 DDHR2H TDHR3H - - 265 18 DDHR2H - - -

Notes:







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AASHTO HS25 LOADING



30ft 2 lane

34.4ft 3 lane

59 4 SSH DSH DSH+ DSH+ 73 5 SSH DSH DSH+ TSH 88 6 SSHRH+ DSH DSHR2H+ TSH 103 7 SSHRH+ DSHR2H+ DSHR2H+ TSH 118 8 SSHRH+ DSHR2H+ DSHR2H++ TSHR2H+ 132 9 SSHRH+ DSHR2H+ DSHR2H++ TSHR2H+ 147 10 SSHRH+ DSHR2H+ TSHR2H+ TSHR2H++ 162 11 DSHR1H DSHR2H++ TSHR2H++ TSHR2H++ 177 12 DSHR1H+ TSHR2H+ TSHR2H++ TSHR3H++ 192 13 DSHR1H+ TSHR3H+ TSHR3H++ DDHR2H+ 206 14 DSHR2H TSHR3H+ DDHR2H+ TDHR2H+ 221 15 DSHR2H DDHR2H+ TDHR2H TDHR3H 236 16 DDHR1H TDHR2H TDHR3H TDHR3H 251 17 DDHR2H TDHR3H TDHR3H - 265 18 DDHR2H TDHR3H - -

Notes:







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AASHTO HS25 LOADING with 2” ASPHALT SURFACING



30ft 2 lane

34.4ft 3 lane

59 4 SSH DSH DSH+ DSH+ 73 5 SSH DSH DSH+ TSH 88 6 SSHRH+ DSH DSHR2H+ TSH 103 7 SSHRH+ DSHR2H+ DSHR2H+ TSH 118 8 SSHRH+ DSHR2H+ DSHR2H++ TSHR2H++ 132 9 SSHRH+ DSHR2H++ DSHR2H++ TSHR2H++ 147 10 DSH DSHR2H++ TSHR2H++ TSHR2H++ 162 11 DSHR1H+ DSHR2H++ TSHR2H++ TSHR3H++ 177 12 DSHR1H++ TSHR2H++ TSHR3H++ TDHR2H 192 13 DSHR2H TSHR3H++ TDHR2H TDHR2H+ 206 14 DSHR2H+ DDHR2H+ TDHR2H TDHR3H 221 15 TSHR3H TDHR2H TDHR3H TDHR3H 236 16 DDHR2H TDHR3H - - 251 17 DDHR2H TDHR3H - - 265 18 DDHR2H - - -

Notes:




longer fatigue life is required the advice of Mabey Bridge & Shore, Inc. engineers should be sought.


for the specified loading. If a heavy deck system is required (see page 13), the tabulated constructions may not be adequate, contact Mabey Bridge & Shore, Inc. engineers for advice.

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ALLOWABLE LOADS ON TRANSOMS & DECK SYSTEMS

GENERAL NOTES 1. The loads given below may be increased by a factor of up to 1.3 if impact is not required. 2. No fatigue requirements have been considered, however, the normal transom and deck systems

upon which all data in this publication is based are suitable for regular use by the axle and wheel loads given below. For specific fatigue requirements, contact Mabey Bridge & Shore, Inc. engineers.

3. For occasional controlled crossings (where the vehicles are driven slowly along the center of the roadway) heavier wheel and axle loads may be permissible. Contact Mabey Bridge & Shore, Inc. engineers for advice.

TRANSOMS FOR SINGLE LANE ROADWAYS – MAXIMUM AXLE LOADS a) Single Axles b) Dual Axles c) Triple Axles

4 ft

28 kips44 kips 28 kips

4 ft

20 kips20 kips 20 kips

4 ft

Specific Notes:

i) Longitudinal spacings of less than 4 ft will reduce the allowable axle loads. ii) There can be no other axle for at least 7.4 ft in either direction beyond the above axles. iii) The minimum transverse wheel spacing on each axle is 6 ft (center to center)

TRANSOMS FOR TWO LANE ROADWAYS – MAXIMUM AXLE LOADS Heavy duty (type HS25) two lane transoms are suitable for two of the above maximum axle loads, one in each lane, side by side, simultaneously. For light duty (type HS20) two lane transoms carrying two lanes of traffic, however, the maximum axle loads should be limited to 80% of the above. STEEL DECKING – MAXIMUM WHEEL LOADS The safe single wheel load is 22 kips. Normal steel deck units of the type, assumed throughout this manual, have been tested to a million cycles of a 22 kip wheel load applied on a contact area of approximately 8” x 20”, plus an additional 30% for dynamic impact, without failure. For applications where heavy wheel loads, high tire pressures or high fatigue requirements are anticipated, heavier deck systems are available. Contact Mabey Bridge & Shore, Inc. engineers for advice.

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BRIDGE FOUNDATIONS

NOTES PERTAINING TO THE BRIDGE ABUTMENT DIAGRAMS

1. Typical foundation layouts required to accept the Mabey Universal Bridge System are shown. This gives the geometric layout of the foundations only. The foundations must be designed by a competent engineer, taking into account the suitability of the soils on which the abutments and piers will bear. In the final analysis, a piled foundation may be required.

2. The foundations should be designed to accept both the in-service loads and the installation

loads. The installation loads, which consist of longitudinal loads as well as vertical and lateral loads, may govern the design when a large bridge is being launched. As the bridge is pushed over the rollers placed on the launch abutment or on piers, the overturning moment thus produced can be severe, and additional concrete or steel may have to be provided to resist this effect.

3. Abutments and piers should be designed such that there is minimal differential deflection

beneath the trusses.

4. The design of the abutments should incorporate casting the backwalls AFTER the bridge is in place to allow for tolerances in the bridge. Starter bars for reinforcing steel should be bent clear of the bridge during installation, and should be omitted completely from areas where jacks are to be used.

5. It is recommended that the anchor bolts for the bearings are NOT cast into the abutment, but

rather, a suitable void is cast at their location. Once the bridge is in position and seated on its bearings, the anchor bolts can be grouted into place. It is essential that all of the bearings on an abutment are set in the same plane to avoid maldistribution of stresses in the bridge. This may necessitate the use of a non-shrink grout beneath the bearings.

6. For temporary bridges, consideration should be given to the removal of the abutments upon

completion of the project. In some instances a timber abutment with a timber backwall may be suitable. Suitable steel beams may also be used for abutment foundations.

7. Piers for multi-span bridges should be designed to accept both the in-service loads and the

installation loads. The overturning effects from the bridge (from wind loads and breaking loads during service, and from wind loads and launch loads during the installation) should be taken into account and provision made.

15

BRIDGE FOUNDATIONS

TYPICAL FOUNDATION LAYOUT

Preferred

Brg.Build AreaElevation of =

C

C

LBridgeLCCCL

L

ELEVATIONABUTMENT

C

ABUTMENT SECTIONSCL=

=

B (Backwall Face)

=

A

Brg.= CL

=

LCLCL

firm &

leve

l

BUILD A

REA

Constructed AfterBridge is in Place

Backwalls

OF BRIDGE

[19" with End Posts]16" min.

MALE END

105 8"

=

105 8"

C

D

PLAN

E

=

CL Bridge LC

GradeFinished

2'-4

3 4"

A

OF BRIDGEFEMALE END

Male EOBSame as

- 5" w/o End Posts Brg. c/c = Bays x 14.76'

Behind BearingsBrg. to BackwallCL Brg. to Backwall

Behind Bearings

+ 5" with End Posts

CL

Launch Direction

2'-4

3 4"

ROADWAY WIDTHS

DIMENSIONS

13.8ft

24.1ft

30ft

34.4ft

A 16’-3” 27’-0” 32’-31/4” 38’-07/8” B 14’-6” 24’-6” 31’-0” 35’-0” C 2’-101/4” 3’-6” 3’-63/8” 3’-91/2” D 53/4”* 61/8”* 63/16”* 63/4”* E 95/8”* 913/16”* 913/16”* 105/16”*

* If End Posts are used subtract 5”. Dimensions D & E include 1” clearance from bridge to backwall face. This should be adjusted to allow for thermal expansion as required.

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MULTIPLE SPAN BRIDGES Where a gap to be bridged is too wide to be economically crossed by a single span structure, it is necessary to provide intermediate piers and install a multiple span bridge. The positioning of the intermediate piers is often dictated by the geology or topography of the site. Where this is not the case, the positioning and quantity of piers to be provided depends upon the most economic balance between the cost of the piers and the cost of the bridge truss construction appropriate to the varying span lengths. The Mabey Universal Bridge System can be configured in one of several ways when forming a multi-span bridge. In all cases a continuous travel surface is maintained across the pier. The heights of the bearings vary at the piers from the abutments depending on the system that is used. For details, refer to Mabey Bridge & Shore, Inc. engineers. TOP PIN OUT The simplest method of accommodating a pier is to simply break the span at the pier by removing the pins from the connection at the top of the truss. Each span shares a bearing at the pier. The bridge is typically installed with the trusses connected continuously at the pier and, once it is in place, the top pins removed. Different slopes for each span can be accommodated using this method. This method can only be used for single story spans. The longitudinal location of the pier(s) is critical in this instance, but limited inaccuracies in the elevation and differential settlement of the piers can be accommodated. SPAN JUNCTION EQUIPMENT When a double story span reaches a pier, connecting to either a single story span or another double story span, span junction equipment must be used. This consists of a pair of end posts which connect together at the deck level. Only one of the end posts is located on the bearings at the pier. Typically the shorter span “hangs” from the longer span. Use of span junction equipment increases the overall length of the bridge by ¼ bay (3.7 ft). CONTINUOUS If a bridge is built as a continuous structure over the piers, the maximum in-service total bending moment, and also the maximum deflection, is reduced. Typically, the maximum shear force in the trusses is increased when considering continuous spans. For longer spans, where the bending moment governs the construction, continuous bridges can result in savings in the trusses. In addition, the longitudinal location of the piers is not critical. At the piers, the trusses bear upon distribution beams, approximately 12ft long, which pick up several strong points along the panels. The elevation of the piers is critical when configuring a bridge as continuous, as a slight change in elevation can result in the bending moments being increased significantly. It is also critical that no differential settlement of the piers is experienced during the life of the bridge. Continuous bridges are not recommended when there is a large difference in the length of the spans as this can lead to uplift at the abutment of the shorter span. SEPARATE BEARINGS The least common solution, involves providing a pier wide enough to accommodate two sets of bearings. Each span bears upon its own bearings. A filler deck unit is required between the two spans.

Any bridging materials can become dangerous if improperly assembled, maintained or used. Bridging materials must only be used as approved by the manufacturer, in accordance with assembly, use, maintenance and weight restrictions. Only properly trained personnel should handle these materials. Representatives of Mabey Bridge & Shore, Inc. should be contacted to obtain information and training. Whilst every effort has been made to ensure the accuracy of all data contained herein, Mabey Bridge & Shore, Inc. reserves the right to amend or adjust the design criteria as may become necessary from time to time. Any person wishing to place reliance on any statement contained herein must not do so without having first obtained express written confirmation from Mabey Bridge & Shore, Inc.

MBSI MU04-01 - 8/31/2006

Mabey Bridge & Shore Inc. ®

6770 Dorsey Road ♦ Baltimore, Maryland 21075 ♦ (410) 379-2800 ♦ FAX: (410) 379-2801

Mabey Inc.6770 Dorsey Road • Elkridge Maryland • 21075 • 410-379-2800 • 410-379-2801

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