MJS Monolith Joint Seal

MJS™ Monolith Joint Seal System

STRUCTURAL TECHNOLOGIES’ MJS™ is a proprietary replacement waterstop monolith joint seal system that controls leakage of water through existing joints, particularly in dams, locks, large retaining walls and other structures.

The system is installed in a drilled hole and uniformly pressurized to offset hydrostatic pressure.

The MJS™ System is a long-lasting solution that holds up to water and joint movement without damaging the system itself.

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mjs dam seal
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Installed in a Drilled Hole
  • Ensures continuity throughout length of joint.
  • System won’t track into opened joint – preventing damage to the dam seal
  • May be removed or replaced
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Maintains Uniform Internal Pressure
  • Offsets hydrostatic pressure from the water source regardless of joint movement
  • Accommodates pressure heads to 150 psi and depths over 300 feet
  • Adapts to variation in weather from -50°F to 120° F
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Overall System Advantages
  • Maintains water control when the joint opens and closes
  • Eliminates need for divers
  • Eliminates need for chemicals to contaminate water supply
  • Easily maintained and serviced
  • Restores original water control features designed into the structure
  • Easy to inspect via remote cameras during and after installation

Concrete Repair Engineering Support

Engineered Solutions:

STRUCTURAL TECHNOLOGIES’ Moisture Control Team provides solution building services for difficult-to-solve moisture problems.
Our specialty is taking on problems where traditional products and design solutions have failed.

Our experts integrate with engineers, owners and builders to assist with initial assessments through design and material selection

Moisture Control Team Leader

Read more about our products and applications on our moisture control solution builder page

Design-Assist & Engineered Product Support

• Investigation Support
• Solution Development
• Budget Development
• Specification Assistance
• Constructability Consulting
• Application Engineering
• Quality Control Programs
• Project-Specific Design-Assist