1. All about Mitre Gates PIANC Report No. 154 Overview
Prepared by:
Eric Johnson, P.E., S.E.
Josh Repp, P.E.
Michael Hough, P.E.

2. Working Group 154 Objectives:
Mitre gates are used in most of the navigation locks in the world and are critical to lock system performance
Identifying “Best Practices” for the design, fabrication, and operation of lock mitre gates
Meetings:
September 2013 Maastricht, Netherlands
February 2014 Brussels, Belgium
September 2014 Ontario, Canada
April 2015 Bremen, Germany
November 2015 Paris, France
November 2016 Seattle, USA

3. Members - Working Group 154

4. Meeting Highlights
Maasbracht Locks Complex (The Netherlands): Remote Operation
Welland Canal Locks 3 thru 7 (Canada): Self-mooring, finger joints
Klaas Siemens (Germany): Fabrication practices and challenges
Chittenden Locks (USA): Composite Contact Blocks
Good overall discussions about challenges,
designs, and best practices that we have
each encountered from the variety of member backgrounds

5. European vs. North American comparison
Differences
Locks and Gates are narrower in Europe
(Europe lock widths 12.5-m, 16-m & 24-m,
North America mostly 33m)
Top & Bottom Hinge Styles
Filling & Emptying devices in gates
Similarities
Pintle/Pivot problems
Contact Block wear
Materials
Seals

6. Report Overview Mitre Gate Systems Mitre Gate Components
Mitre Gate Design Issues and Guidance
Gate and Component Materials
Mitre Gate Seals
Ancillary Components
Operations and Maintenance
Conclusions
References

7. Chapter 1: Systems Goals: Identify History Terminology
Selection Process
Geometry
Structural System

8. Chapter 1: Systems (Selection Process)

9. Chapter 1: Systems (Structural System)
Vertically Framed Gate
Horizontally Framed Gate

10. Chapter 2: Components Goals: Structural Arrangements
Hinges / Gudgeon / Pintles (Pivots)
Anchorage
Heel (Quoin) / Mitre Blocks
Diagonals
Operating Machinery
Control System

11. Chapter 2: Components (Structural Arrangements)
Bottom pintle, top hinge arrangement b)
Bottom hinge, top pintle arrangement c)
Gate suspension
outside hinges d)
Application of buoyancy tanks

12. Chapter 2: Components (Pivots)
Free Pintle
Free Pintle
Floating Pintle
Fixed Pintle

13. Chapter 2: Components (Anchorages)
Top hinge design typical in Europe (ROK Design of Locks – Part 1)
Figure 2-
Typical Upper Mississippi (3-pin) lapped

14. Chapter 2: Components (Anchorages)
Five-pin anchorage (USACE, Greenup Lock).
Five-pin anchorage cross-section with spherical bushings (USACE, The Dalles Lock)

15. Chapter 3: Design Issues and Guidance
Goals:
Global Design Guidance
Design Load Conditions
Fatigue
Connections
Flexibility / Stiffness
Gate Recess Design
High Lift Lock Gates

16. Chapter 3: Design Issues and Guidance

17. Chapter 3: Design Issues and Guidance
Load Considerations (Usual and Unusual Conditions)
Impact Loads (PIANC WG 151)
Environmental Load (Waves, Ice, Silt, Obstructions)
Construction
Load Redistributions with Worn / Misaligned Gates
Analysis Considerations
2D vs. 3D Modeling
Fatigue
Connections
High Lift Locks

18. Chapter 4: Gate Components and Materials
Goals:
Framing Materials
Contact Materials
Seals Materials
Hinge Materials
Sliding Materials

19. Chapter 4: Gate Components and Materials
A small FRP polyester mitre gate at Werkendam the Netherlands after working life of approx. 13 years in brackish water

20. Chapter 4: Gate Components and Materials
FRP mitre gates in the Wilhelmina Canal Tilburg, the Netherlands

21. Chapter 4: Gate Components and Materials
High Strength Fibre Reinforced Concrete
Timber
Example of FRC sliding gate
at IJburg, Amsterdam
Example of a timber monumental mitre gate at the Wilhelmina Canal, Tilburg
(the Netherlands)

22. Chapter 5: Mitre Gate Seals
Miter Gate Seals
Seals serve an important purpose in sealing the perimeter of the gate to the lock walls and sills
Bottom Seal
The bottom seal of the gate against the lock sill is important since the high water pressures can cause excessive leakage and damaging vibrations to the gate
Side Seal
The side seals of the gate against the lock walls are primarily for water retention

23. Chapter 5: Mitre Gate Seals
Side Seals
Side seals run full-height of the quoin blocks
Used to improve gate leak asthetic performance
Be careful – Side seals can mask quoin block alignment issues
Bottom Seals
Located at the bottom sill
Limits leakage induced vibration

24. Chapter 5: Mitre Gate Seals
Bottom Seal Example Types
Inclined J-bulb Seal
Round Rubber Seal

25. Chapter 5: Mitre Gate Seals
There are several factors to consider in choosing a seal:
Durability
Maintenance Intervals
Leakage Limits (Cosmetic and Hydrologic)
Load Transfer Ability (Stiffness)
Environmental Conditions (Temperature, UV exposure)

26. Chapter 6: Ancillary Components
Lubrication
Impact Protection

27. Chapter 6: Ancillary Components
Lubrication
Lubrication is essential to proper operation of mitre gates.
Top hinge, pintle, operating strut arm connection
Challenges include:
High loads
Small angles of rotation
Low cycles of movement
Joints only rotate approximately 70º out of their 365º circumference, making it difficult for the lubrication to uniformly distribute.
Self-lubricating materials offer potential for improved performance.
Corrosion resistant
Examples: Kamatics KAron V, Tenmat Ferroform/Ferroglide

28. Chapter 6: Ancillary Components
Pintle Ball Lubrication Grease Lines
Used to evenly distribute grease across the pintle ball circumference
Improves performance and corrosion resistance
Self Lubricating Pintle
Improved service performance
Corrosion resistant
Eliminates need for grease systems
Higher initial cost

29. Chapter 6: Ancillary Components
Impact Protection
Mitre gates are very susceptible to impact damage by vessels entering and leaving the lock.
Protection Feature Types
Gate fenders, gate bumpers, guard gates, and ship arrestors
Fender Materials
Timber, metal, polyethylene, and rubber

30. Chapter 6: Ancillary Components
UHMW-PE Glass Reinforced Gate Fenders
Low coefficient of sliding friction
Reduces “Stick-Slip” behavior on contact
Long service life
Timber Gate Fenders
Economical
Good energy absorption
Potentially shorter service life than UHMW - rotting

31. Chapter 6: Ancillary Components
Automated Cable Ship Arrestor System
Design reduces the potential for mitre gate damage due to vessel impact
These can be expensive constructions for which the investments will have to be weighed against the risk of failure of the water retaining structure and navigation interruptions
Not common in the USA

32. Chapter 7: Operations and Maintenance
Spare Parts
Spare Gates
Gate Repair
Ice and Debris Management
Inspections

33. Chapter 7: Operations and Maintenance
Spare Parts
The operation of mitre gates requires stocking spare parts for the most fragile parts on a permanent basis.
Split into two categories:
Emergency Parts
Replacement cannot be foreseen and therefore cannot be scheduled
Anchorage bars and linkages, pintles, gudgeon pins, diagonal bars, and operating strut arms
Scheduled Replacement Parts
Those parts which will need to be replaced due to normal wear and tear
Pintle bushings, gudgeon pin bushings, anchorage bushings, gate actuator parts and sensors, fenders, seals, and sensors

34. Chapter 7: Operations and Maintenance
Spare Gates
Typically, the acceptable time period for navigation interruption is much shorter than the time required for major repairs or replacement.
This is why there is a need for spare mitre gates that can be placed into operation in a relatively short amount of time.
Depending on gate size and crane capacities, gates are stored at locks, on barges or in special buildings to preserve their condition.
A lifecycle analysis needs to be performed to determine the costs of navigation interruption compared to the costs of having spare gates.

35. Chapter 7: Operations and Maintenance
Gate Repair
Gate weight, site accessibility and navigation interruption time will drive the need for repairing the gate in-place or removal of the gate.
The mitre gate may contain lifting lugs that were used during construction
Facilitates handling during shop fabrication, erection, and initial placement of the gate
Facilitates maintenance operations
Larger gates should be designed with jacking points
Allows the gate to be moved vertically using hydraulic jacks for removal or maintenance of the pintle or seals

36. Chapter 7: Operations and Maintenance
Ice and Debris Management
Ice prevention and ice breaking measures require flexibility. Why?
Disparity of the inland waterways
Geographical location within the country
Type of inland waterway traffic
High volume air bubbler systems
Move ice and debris from the gate recess area such that the gate may fully recess
Low volume air systems or propeller systems can be attached to the gates to prevent the build-up of ice on the gates
Electric thermal strip systems

37. Chapter 7: Operations and Maintenance
Inspections
Underwater divers
Historical method
An alternative technique
Refers to a process which replaces and prevents diving (human immersion)
Remote camera inspection
A complementary technique
Submerged or non-submerged assistance operations provided during an underwater diving operation
The main objective of complementary techniques to diving is to improve the safety of the underwater operations and reduce the risks faced by divers

38. Chapter 8: Conclusions
Mitre gates have a long history and have been used in a wide variety of conditions, heights, and widths
Vertically framed more economical and easier to maintain for height-to-width ratios of less than about 0.7
Top and Bottom Hinges that accommodate tolerances for fabrication, wear, and construction improves load transfer and longevity
Design to accommodate ease of future maintenance
Consider new materials weighing advantages and limits
Standardization

39. Questions? Feedback? Eric.O.Johnson@usace.army.mil