SJS-Seismic Joint System
&
SJS-FP--For Plaza Decks & Split Slabs

The SJS by EMSEAL is comprised of silicone-and-impregnated-foam hybrid components that ensure watertightness, absorb sound, dampen vibration and offer uncomplicated installation.

Created from the latest evolution in the field-proven technology that EMSEAL has used for 30 years of sealing horizontal plane joints with impregnated foam sealants, the SJS is constructed from two horizontal joints pre-assembled in parallel adjacent to a heavy-duty extruded aluminum spline. The spline acts as a receptor for attaching the surface-mounted traffic plates that bear vehicle and other loads. The result is a system that offers features and benefits not found in alternative products intended for large horizontal structural joint gaps.

Features:
Watertight – The tensionless silicone bellows are installed flush to the mounting height of the system and just below the coverplate ensuring watertightness at the traffic surface. This eliminates the need for ineffective moisture barriers and secondary gutter systems.

Sound Attenuation – The flanking impregnated foam and silicone hybrid dampens sound and shock effectively. When installed over EMSEAL-supplied elastomeric nosing material, the result is arguably the quietest watertight coverplate system available.

Easier Installation – Using non-invasive anchoring the SJS eliminates hard metal-to-concrete connections as well as intrusive pins, anchors, screws, bolts or tracks, trays or rails. The system is locked to the joint faces by the backpressure of the foam and an epoxy adhesive, and by the weight of the assembly.

Self-Locating Coverplate Screws – The center spline is a continuous receptor for the coverplate screws that are self-tapped into the anchor channel. This dramatically reduces the installation-related problems of locating self-centering, sliding ball devices and pantographs. The probability of screws being left out is eliminated ensuring proper anchoring.

Self-Locking, Vibration-Dampened Screws – Vibration in systems that rely on metal-to-metal connections and contact points is the main cause of screw loosening. SJS by EMSEAL minimizes vibration through the dampening action of the massive and continuous springs of impregnated foam along the entire length of the joint. In addition, 30 pounds of force is required to loosen the screws offering excellent screw tightness without the need for thread-lock compounds.

Field-Adjustable Plate Support – Concrete in new and retrofit applications is inevitably uneven across and along the joint. The SJS is installed over a leveling-bed of EMSEAL-supplied elastomeric nosing material providing the ability to fine-tune the support of coverplate sections reducing rocking and noise caused by unleveled plates. Systems that attach or utilize intrusive extruded rails to receive sliding ball and socket devices cannot be adjusted to eliminate unevenness across and down the length of the joint.

Continuity of Seal – All EMSEAL expansion joint systems feature continuity of seal through changes in plane and direction –– an essential performance differentiator. Fabricated transitions from deck to wall, at curbs, sidewalks, parapets, tees, and crosses are available with the SJS.

Finite Element Analysis (FEA) Compiled Safety Factors – Prior to field trials, the SJS by EMSEAL was modeled using FEA to determine the suitability of design to worst case possible parking deck loads. Under the scenario of a 4,000 lb vehicle skidding across the joint system to full stop once past the coverplate, FEA modeling predicted lateral displacement of the coverplate of less than 3/4-inches (19mm) and safety factors in key components as follows:
FEA Safety Factors:
Traffic Plate - 5 ; Screws - 11 ; Spline Pins - 10; Center Spline - 7

SJS-SYSTEM in STADIUMS--Watertight system for large concourse and tread and riser joints.  Shown here replacing rubber-encased coverplate.

(click images to enlarge)

Link to Watertight Stadium Joint Selection Guide