Briefly About Us

Our motto is “Sky is the Limit”. Since 1993 we have been installing and supplying all types of expansion joints for bridges in all regions of Russia and all over the world.

We manufacture and supply:
- Bridge expansion joints;
- Protective transition areas of expansion joints;
- Waterproofing for bridges, tunnels and subways;
- Binders, mastics, impregnations, emulsions and primers for road construction;
If you want to have a job done well, you should hire a professional. We meet your most ambitious expectations and help you save your money.

THE PRAS GROUP OF COMPANIES welcomes you to our company's website!
We are glad that you have made the right decision. When choosing bridge expansion joints, a crucial task is to select a reliable supplier that ensures timely deliveries, installation and maintainability of the structures within the warranty period. We also provide professional advice, designer supervision and bespoke solutions tailored to suit your needs.

Our company was founded in 1993 by the leading experts of the Bridge Laboratory of SoyuzDorNII (Road Construction R&D Institute). With the benefit of many years of research and development and the best technical solutions based on international practices, we offer our customers only reliable and proven constructions and materials.

PRAS GC IS THE DEVELOPER AND PATENT HOLDER (since 2002) OF THE PLUG EXPANSION JOINT "FORMOSHOV®" (an asphaltic plug expansion joint), which was developed especially for the Russian climate; its analogues are expansion joints of Thorma-Joint®, Nafutekt Plus, C-Joint®, Lafrentz, etc.

PRAS GC IS A DEVELOPER AND SUPPLIER of protective transition areas of expansion joints, including the Transition Butt Joint (TBJ); based on the TBJ design, an equivalent structure - SEGMC (strong-elastic granite-mastic composition) was developed.

PRAS GC IS A DEVELOPER AND SUPPLIER of praSCrete that is plastic concrete intended for the construction of protective transition areas of bridge expansion joints. In physical and mechanical properties praSCrete is superior to its analogues such as Wabo®Crete II, Strelax, etc.

PRAS GC IS THE DEVELOPER of ULTRAMAST seamless spray-applied waterproofing, and of ULTRAMOST bridge waterproofing.PRAS GC MANUFACTURES POLYMER- MODIFIED BITUMINOUS SEALANTS, POLYMER-BITUMEN BINDERS (PBB), MASTIC FILLERS, MASTIC SEALANTS FOR EXPANSION JOINTS, WATERPROOFING MASTICS, AND WATERPROOFING SYSTEMS.

PRAS GC OFFERS INSTALLATION OF EXPANSION JOINTS FOR BRIDGE STRUCTURES, WATERPROOFING APPLICATION AND BRIDGE REPAIRS.

FORMOSHOV Expansion Joints: Stone Mastic Plug Expansion Joints (asphaltic plug joints) have been recommended for use by the State Committee for Construction of Russia since 2003 for all climatic zones, including areas with extreme weather conditions. The joints comply with the ODM 218.2.025-2012 Requirements on "Expansion joints of automobile bridges. Federal Road Agency 2012”. FORMOSHOV expansion joints are used for bridge structures of any motorways and can accomodate movements of end sections from 10 mm to 60 mm. Some of the Thorma-Joint BJ (UK) and Nafutekt Plus (Germany) asphalt plug joints are similar in design. These Thorma-Joint BJ (UK) and Nafutekt Plus (Germany) joints designed to use in European climatic zones are also used in Russia and their characteristics and structures are similar to FORMOSHOV ones. The FORMOSHOV expansion joints comprise the special ULTRASHOV binder which performance characteristics surpass those of its counterparts, namely BJ-200 Super and Nafutekt Plus binders, as well as the ULTRASTONE mixture of specially-graded cubiform crushed stone treated with a unique polymeric composition. The special treatment of each particle of the ULTRASTONE granite mixture gives uniformity to the FORMOSHOV stone mastic mixture, which prevents FORMOSHOV expansion joints from cracking and partial destruction in service, unlike similar structures (using washed aggregate) or joints made of poor-quality or non- certified materials in a non-professional manner.

T. I. S UBK (UNIBLOK) SERIES EXPANSION JOINTS ARE RUBBER-METAL EXPANSION JOINTS MADE OF HIGH-QUALITY NEOPRENE REINFORCED WITH STEEL PLATES. THEY ARE USED FOR ALL TYPES OF BRIDGES, TRESTLES, OVERPASSES, PARKING LOTS AND CAN ACCOMMODATE LONGITUDINAL MOVEMENTS UP TO 350 MM, TRANSVERSE MOVEMENTS UP TO 300 MM AND VERTICAL ONES UP TO 40 MM. UNIBLOK (UBK series) is a steel-reinforced elastomeric (neoprene) molded monolithic system. The type and size of UNIBLOCK sections are selected depending on the movements predicted in service and the characteristics of the structure. The design is a neoprene molded reinforced section. Different sizes are available (Table 1). Fast and easy to install. No embedded parts. Self-cleaning design. The joints are installed after the asphalt concrete is laid. When the asphalt-concrete surfacing is under repair, expansion joints can be dismantled and adjusted to the new road surface level. This structure is one of the most reliable today. Over 200,000 meters of UNIBLOCK expansion joints are used worldwide, more than 2,000 meters of which are used in Russia.

The expansion joint design comprises steel edges with different types of profiles (Z, F or C) fixed on the mating structural elements of the bridge, and a rubber (neoprene) seal locked into the edges with dovetail joints. Expansion joints of the MMSH SP series also comprise intermediate beams with rubber seals fixed on both ends. The intermediate beam is mounted on traverses which ends are placed in the niches of the mating elements and can move freely in the longitudinal direction. Seal deformations are synchronized by special devices attached to the edges and to the longitudinal beam. The front and side views of section lengths and edge outlines and of the longitudinal beam are determined by the configuration of the bridge roadway and sidewalks. To accommodate movements of mating elements up to 120 mm the expansion joints MMSH OP-50,80,100,120 with flexible rubber seals embedded in metal edges at the level of the asphalt concrete surfacing are used (their closest analogues are Mauer expansion joints manufactured by Maurer Soёhne, Mageba expansion joints and the K8, OP-DSH ones). This design differs from its analogues. First, the dovetail configuration is used for seals locking and, second, it comprises profile details machined from sheet metal. Edge metal structures are embedded in the span concrete floor and/or abutment with grouted anchors or welded to the deck plate of orthotropic bridges. To accommodate movements of mating elements from 160 to 320 mm the modular expansion joints MMSH MP 160, 200, 240, 280, 320 are used. Comprising simple mechanical movement synchronizers, they are easy to manufacture and highly reliable in contrast to imported expansion joints. Moreover, these joints have all advantages of imported ones, such as noiselessness, watertightness, etc.

Focusing on reliability and quality, our prices are easily affordable. All products are certified and meet the safety requirements/quality standards/GOST state standards.
We would like to offer you the quickest service and perfect quality at a convenient time and attractively-priced!

Maintenance-free TBJ (transition butt joints).

Dynamic impact and rutting in the expansion joint area;
Destruction of the abutment of the road pavement to the expansion joint;
Weak adhesion and poor compaction of asphalt concrete in the area adjacent to the expansion joint;
Effect of salts, corrosive waters, leaks within the expansion joint.

Reliable solution to the problem of expansion joint failure is the use of TBJ transition areas.

TBJ transition areas are developed by the leading experts of the Bridges Laboratory of FSUE “SoyuzDorNII”;
Accessories delivered at place in the Russian Federation and all over the world and consultancy support;
Quick and partial repair service in case of localized damage
20,000 linear meters in service since 2002.

TBJ Use

Transition areas between expansion joints and road pavement
Grouting of expansion (movement) joints in various structures
Reducing dynamic traffic impact on expansion joints
Prevention of rutting in the area of expansion joints
Leveling and protective covering for repair and maintenance of existing joints
Areas adjacent to railway lines at railway crossings
Repair and maintenance of edges of reinforced concrete structures and cantilevers.

Applications: bridge structures, civil-engineering structures of transportation facilities, parking lots, railway crossings and areas adjacent to railway lines.

Description

The TBJ transition butt joint consists of the ULTRAPREN high-quality bitumen-polymer binder and the ULTRASTONE mixture of well-graded cubiform crushed granite stone treated with a special polymeric composition.

Packaging Accessories for the installation of TBJ joints are supplied in the following kits:

ULTRAPREN in 15 kg adhesive bags

ULTRASTONE in 25 kg bags

Reliable protection of the expansion joint from damage
Maintenance-free service life up to 10 years
Quick and easy installation, manufacturer's warranty
Low cost of materials and installation

A special compound modified with elastomers for the construction and repair of transition zones of expansion joints for use in bridge decks, freeways, any engineering constructions and in the construction of transportation facilities.

praSCrete Use

Transition areas between expansion joints and road pavement
Grouting of expansion (movement) joints in various structures
Reducing dynamic traffic impact on expansion joints
Prevention of rutting in the area of expansion joints
Leveling and protective covering for repair and maintenance of existing joints
Areas adjacent to railway lines at railway crossings
Repair and maintenance of edges of reinforced concrete structures and cantilevers.

Applications: bridge structures, civil-engineering structures of transportation facilities, parking lots, railway crossings and areas adjacent to railway lines. Analogues of praSCrete are Wabo-Crete II and Strelax Wabocrete.

praSCrete consists of two elastomeric components A and B, and component C which is a mineral mixture of different powder fractions from fine rheologically active powder to high-strength particles up to 5 mm. The component A (resin) is a black low-viscosity liquid, the component B (activator) is a transparent viscous liquid, and the component C (filler) is a well-graded mineral mixture.

Advantages

Durability, strength, resistance to wear, flexibility
Resistant to ozone, UV, aggressive media and chemicals.
Ready for use in 2-2.5 hours after finishing.
Ability to work on small areas or with limited windows of time.
Prevention of rutting in the expansion joint area.
Protecting expansion joints from traffic impacts and evenly dispersing traffic loads.
High adhesion to metal and concrete substrates.

Substrate preparation:

Requirements:

The concrete substrates must be free from contaminants and dust removed. The substrate must be dry and sound. Newly placed concrete must be cured minimum of 14 days. All traces of contaminants, such as oil, grease, chemicals, and laitance, must be removed. Weak and contaminated concrete must be removed. Tensile strength of the concrete substrate must be at least 1.5 MPa.

Metal surfaces must be sandblasted or treated by other mechanical methods to Sa 2 ^½standard.

To install an expansion joint on substrates made of other materials, please consult a specialist.

Consumption:

Material consumption depends on various factors. One set of praSCrete polymer concrete A+B+C of 18.7 kg is enough for filling 10 dm3 +/- 2%. The exact consumption is adjusted by testing in the field. Preparation of the praSCrete mixture Pour entire contents of components A and B into a clean dry container of 20 liters or more, mix components A + B with a mixer for 15-45 seconds until the mixture becomes homogenous. Add component C slowly and continue mixing for 1-1.5 minutes until the mixture becomes homogenous. Use a low-speed electric mixer (350-400 rpm) equipped with a butterfly paddle to mix the components. → Do not use spiral paddles. Works can be carried out in the temperature range from +1°С to +45C^о. In cold weather ensure that all components and tools are warm to facilitate mixing. In hot weather avoid the components being heated and keep away from direct sunlight.

Polymerization: praSCrete

Pouring to the depth of more than 120 mm is performed in several steps. Allow each layer to harden before pouring the next one. Works can be performed at ambient temperatures ranging from + 1°С to +45°С. At 20°С curing starts in 20 minutes. Approximate time before the commencement of service: 2-2.5 hours. Complete polymerization: up to 72 hours. The formwork must be covered with plastic strips or other materials to dismantle it easily.

Equipment cleaning Cleaning must be carried out at a sufficient distance from the work site. Application equipment can be cleaned with solvents (Xylene) immediately after use. Safety precautions must be observed.

ULTRAMOST is a two-component system applied mechanically with an airless spraying unit. Waterproofing is applied with a two-channel sprayer equipped with special nozzles.

Bridges are complex engineering structures which operational reliability depends not only on their correct design, but also on the use of appropriate materials to ensure the long-term durability. One of the causes of premature bridge failure is concrete degradation and reinforcement corrosion of decks and beams of superstructures due to poor waterproofing.

Waterproofing of bridges must comply with the requirements of SNiP2.05.03-84 “Bridges and Pipes", VSN 32-81 "Guidelines for hydraulic insulation of structures of Bridges and Pipes railway, automobile and city roads". However, the requirements specified in these documents for waterproofing of bridge structures, design and technologies of road pavements, and waterproofing materials cannot provide reliable protection of reinforced concrete load-bearing structures from corrosive damage by water and dissolved salts penetrating through the pavement. At present, four main types of materials are used for waterproofing of bridge decks and road beds of transportation infrastructure:

Sheet-applied welded or adhesive waterproofing membranes;
"Hot-" and "cold-applied" waterproofing mastics;
Sheet-applied mastic waterproofing;

Bitumen latex emulsions (liquid rubbers).

However, in practice sheet-applied welded waterproofing membranes are the most often used in the construction and repair of bridges and motorways, which is about 85% of the total number of structures and only 15% of the market accrue to new technologies. To change that and solve this global challenge for road pavement waterproofing we decided to develop a special crack- prevention membrane which would allow asphalt concrete or poured asphalt be laid directly onto the surface of waterproofing material.

We supply rubber bearings (RB) used in various bridge structures, trestles and overpasses, as well as in different engineering structures when it is necessary to transfer vertical and horizontal loads from the structure to the support unit and to provide linear or angular movements due to elastic shear deformation.

Our rubber bearings can be used in any climatic zone:

- for different technological constructions (ramps, supporting and access trestles, etc.);
- in civil engineering for different buildings and constructions;
- as anti-vibration mounts when installing different equipment, for example, machine tools, presses, etc.;
- as technological devices in construction, e.g., for incrementally launched bridges.

RB types and designations

Rubber bearings are classified:

- according to the degree of flexibility:

a) free bearings (RB)
b) guided sliding bearings, including bearings displacing in the longitudinal direction (LRB) and in the transverse direction (TPRB);
c) fixed bearings (FRB)

- according to the modification:

a) RB: laminated rubber bearings encapsulated by a rubber cover;
b) RB_s: rubber bearings designed for seismic areas;
c) RB_c: rubber bearings with top and bottom checker plates to transfer horizontal force to the structure.

- according to rubber grade:

a) RB-N: bearings made of NO-68-1 rubber. Application: estimated operating temperature higher than -40⁰C.
b) RB SO: bearings made of IRP-1347-1 rubber with lateral cover made of NO-68-1 ozone-resistant rubber. Application: operating temperatures higher than -55⁰C.

Note: the design sub-zero air temperature is assumed according to Standard SNiP 23-01-99 as the average outside temperature of the coldest five-day period in the construction area, reliability of 0.92 for concrete and reinforced concrete structures and 0.98 for steel structures and parts of steel-reinforced concrete structures.

- by type and sizes: the design and dimensions of bearings are selected depending on design load and displacements.

Reference table of rubber bearings (RB)

To design or order rubber bearings (RB), please refer to the following table:

Mastics and polymer-bitumen binders

Production of binders

We have been producing bitumen-polymer materials for road, industrial and civil construction for over 15 years.
We manufacture products superior in performance requirements and quality to their analogues presented on today's market of construction materials.
All products meet the requirements of GOST and industry standards and even surpass the most of them.
In addition to the items produced according to our designs, we can manufacture items according to the customers need based on customized performance characteristics.
Our production facilities offer the following materials:
- bitumen polymer-modified binders (BPB) based on SBS block copolymers;
- composite organic binders (COB);
- mastics and compositions for filling construction joints and cracks in any coatings;
- priming compositions and impregnating solutions for road construction and repair of asphalt concrete;
- mixtures and impregnating compositions such as Dorsan and Slurry Seal
- high binder anionic bitumen emulsions (ABE) and cationic bitumen emulsion (CBE);
- ULTRAMAST and ULTRAMOST liquid spray-applied waterproofing rubber

Installation and repair of expansion joints on bridges, trestles and overpasses

We work for you

Do you need a professional installation of expansion joints on bridges, waterproofing of bridges, tunnels and underground structures? Our specialists with 20 years of experience in the installation of bridge structures perform all the work required at high quality within the specified time frame. Warranty is provided. Would you like to estimate your project on installation and repair of expansion joints, waterproofing of bridges and underground structures, or components and materials? Please send your engineering documentation to e-mail: info@formoshov.com or leave your phone number in the form below and we will contact you.

Licenses and certificates