Welesgard solution for Steel and Concrete bridges protection СИЛА СОЛНЦА И ВОДЫ
Introduction Road or rail bridges, concrete or steel, all need protection to stop them from corroding or eroding. Welesgard coatings and waterproofing membrane offer long term protection with minimize downtime caused by weather conditions (such as low temperature, high relative humidity and dew point restriction) for new construction as well as for maintenance Welesgard solutions for bridges protection: Steel structures: Steel corrosion protection systems Steel maintenance systems Steel cable protection systems Concrete structures: Concrete protection systems Bridge decks: Steel and concrete bridge deck waterproofing Asphalt pavement
1. STEEL STRUCTURES Steel corrosion protection systems Steel maintenance systems Steel cable protection systems
Steel bridges. Overview Modern bridges are designed to last for at least 120 years, therefore, performance of the protective coating system is a critical factor. The minimum requirements for coating systems are currently as follows: No maintenance for 15 years. Minor maintenance from 15 years. Major maintenance after 25 years. Selection of a suitable coating system is determined by following factors: Corrosivity category (environment in which the bridge is situated); Durability of coating system; Type of painted surface (new structures or maintenance); Surface preparation; Condition during application (temperature, relative humidity and dew point); Minimum and maximum recoat time; Resistance to mechanical damage during transportation; Economic efficiency.
Steel bridges. Advantages of Welesgard moisture cured polyurethane coatings + Provide long term (at least 30 years) protection + Can be applied at at high relative humidity (up to 99%) and low temperatures up to -15 C. + No dew-point restrictions. Application conditions for traditional coatings Epoxy coatings Two-component PU coatings Maximum Relative Humidity during cure: Minimum air and substrate temperature: Dew-point: 80-85% 80-85% 10 C (for pure epoxy and standard epoxy mastics) -5 C (for winter grade epoxy-mastic) The temperature of the substrate should be at least 3 C above the dew point of the air 0 C + Single-component materials, and as a result: no pot life limitation and no mixing errors; + lowed immersion in fresh or salt water and not afraid rain or fog within 30 minutes after application. + No maximum recoat time limitation. + Suitable for various type of surfaces. + High resistance to abrasion and impact.
Only exterior Steel bridges. Systems for new construction HO 2 O 2 UV Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Zn Blast cleaned (at least to Sa 2½) steel surface Zn uminum pigments. Zinc pigments. MIO (micaceous iron oxide) pigments. Primer: WG-Ferrogalvanic - unique system with zinc and MIO. Provide excellent cathodic and barrier protection. As an independent coating protect up to 5 years. Intermediate coat: WG-Weleflex intermediate coating with MIO. Provide barrier protection. Top coats: WG-Sulacover an aliphatic PU topcoat. Excellent UV and weathering resistance. Available in different colors (RAL). WG-Welesilver an aromatic PU topcoat with aluminum pigments. Excellent UV and weathering resistance. Color: silver metallic
Only exterior Steel bridges. Maintenance systems HO 2 O 2 UV For protection over then 15 years Existing rust Power or Hand tool cleaned (St 2) steel surface uminum pigments. MIO (micaceous iron oxide) pigments. Primer: WG-Welestone surface tolerant primer with aluminum and MIO. Provide perfect barrier protection. Intermediate coat: WG-Weleflex intermediate coating with MIO. Provide barrier protection. Top coats: WG-Sulacover aliphatic PU top coating. Excellent UV and weathering resistance. Available in different colors (RAL). WG-Welesilver aromatic PU top coating with aluminum pigments. Excellent UV and weathering resistance. Color: silver metallic
Steel bridges. Exterior and Interior coating systems for new construction Exterior: 1 st : WG-Ferrogalvanic (shop application) 2 nd : WG-Weleflex (shop or site application) 3 rd : WG-Sulacover or WG-Welesilver (site application) The cross section of bridge beams Interior: 1 st : WG-Ferrogalvanic (shop application) 2 nd : WG-Weleflex (shop or site application) Interior Exterior
Steel bridges. Exterior and Interior coating systems for maintenance Exterior: 1 st : WG-Welestone 2 nd : WG-Weleflex (for protection over then 15 years) 3 rd : WG-Sulacover or WG-Welesilver The cross section of bridge beams Interior: 1 st : WG-Welestone(shop application) 2 nd : WG-Welestone(shop or site application) Interior Exterior
Steel bridges. Coating systems pre-qualifications Russian Highways Agency (TSNIIS) Russian Rail Agency (VNIZHT) Coating systems Surface prep. ISO 8501-1 Name Primer Intermediate coat Top coat DFT, µm Name DFT, µm Name Total DFT, µm Expected durability, years DFT, µm TSNIIS VNIZHT 1. New structure 1. Exterior Sa 2½ WG-Ferrogalvanic 80-100 WG-Weleflex 80-100 WG-Sulacover 60-80 240-260 25 25 2. Interior Sa 2½ WG-Ferrogalvanic 80-100 WG-Weleflex 80-100 - - 160-180 25 25 3. Exterior 4. Interior Sa 2½, St 3 Sa 2½, St 3 2. Maintenance WG-Welestone 80-100 - - WG-Sulacover 60-80 160-180 10 10 WG-Welestone 80-100 - - WG-Welestone 60-80 140-160 10 10
Steel bridges. HSFG bolted connections The friction surfaces of the HSFG (High Strength Friction Grip) are usually unpainted. Hence, they should be blast cleaned before the parts are finally bolted together. It is not technological and require additional costs. The coefficient of friction of the surfaces primed with WG-Ferrogalvanic 0,463... 0,506. WG-Ferrogalvanic was approved for protection of the friction surfaces of the HSFG bolted connections. Typical average values for coefficient of friction (µf) Treatment of surface Coeff. of friction (µf) Clean mill scale 0,33 Sand blasted surface 0,48 Surfaces blasted with shot or grit and hot-dip galvanized Surfaces primed with WG-Ferrogalvanic 0,10 0,463-0,506
Steel bridges. Steel cable protection systems An unique protective coating system, especially designed for the protection of structural steel cables on cable-stayed bridge structures. 1 st : 80-100 µm WG-Welestone 2 nd : 80-100 µm WG-Welestone or 80-100 µm WG-Sulacover Properties: Excellent corrosion protection characteristics. Flexible, even at low temperatures. High UV and weathering resistance. Suitable for steel and galvanized steel surfaces.
2. CONCRETE STRUCTURES Concrete protection systems
Concrete bridges. Overview To improve the performance and durability of reinforced concrete surfaces of bridge structures protection systems are frequently required. Benefits of concrete protection: Protection from carbonation; Protection from chloride penetration; Protection of reinforcing steel against corrosion; Protection against frost; UV resistance; Surface beautification; Easy to clean surface;
Concrete bridges. Protections areas Splash and tidal zones Immersion in sea or fresh water, buried in soil
Concrete bridges. Welesgard concrete protection systems Corrosion environment Coating systems Total DFT C3, C4, C5-I, C5-M Splash and tidal zones Immersion in sea or fresh water, buried in soil 40 µm WG-Weleflex Sealer 80-100 µm WG-Welefleх 60-80 µm WG-Sulacover 40 µm WG-Weleflex Sealer 2 х100 µm WG-Welefleх 80 µm WG-Sulacover 40 µm WG-Weleflex Sealer 2 х150 µm WG-Weleforce 40 µm WG-Weleflex Sealer 120 µm WG-Welefleх 80 µm WG-Sulacover 40 µm WG-Weleflex Sealer 250 µm WG-Weleforce 180-220 µm 320 µm 340 µm 240 µm 290 µm WG-Weleflex Sealer WG-Welefleх WG-Sulacover WG-Weleforce moisture cured polyurethane deep penetrating sealer for porous mineral surfaces. Provide excellent adhesion of subsequent coatings to the substrate. moisture cured polyurethane coating with MIO. Provide excellent barrier protection. an aliphatic moisture cured polyurethane topcoat with excellent UV and weathering resistance. a glass flake reinforced epoxy coating for extreme exposure.
Concrete bridges. Welesgard concrete protection systems test Coating system: WG-Weleflex Sealer 40 µm WG-Weleflex 80-100 µm WG-Sulacover 60 µm Total DFT: 200-220 µm Tested for: I. Water penetration (GOST 31383-2008) II. Water absorption (GOST 12730.3-78) III. Frost resistant (GOST 31383-2008) IV. Abrasion resistance (GOST 13087-81) V. Adhesion (pull off test) I. WATER PENETRATION TEST Equipment for determination of water penetration RESULTS: Specimens Concrete with coatings A. Front pressing: B: Backside pressing: Test schema A B 1. Test specimens (concrete) 2. Protective coating 3. Water supply direction Pressure of water before wet spots formation 1,8 Mpa 0,8 MPa Concrete markes W18 W8 Concrete without coatings A. Front pressing: 0,4 Mpa W4 A. Pressing of water from front B. Pressing of water from backside
Concrete bridges. Welesgard concrete protection systems test II. WATER ABSORPTION TEST Specimens Concrete with coatings Concrete without coatings Weight before immersion, m 0, g Weight after immersion, m 1, g Δm, г W, % 679,3 683,1 3,8 0,6 797,8 801,2 3,4 0,4 756,9 759,7 2,8 0,4 809,3 840,9 31,6 3,9 799,4 832,5 33,1 4,1 752,8 783,8 31,5 4,2 Average value Wa, % 0,5 4,1 III. FROST RESISTANT TEST Freezing in 5% NaCl solution From +10 C to -10 C to -50 C to -10 C (5 hours) without coatings with coatings 500 Freezing- Thawing cycles = 20 test cycles Thawing in 5% NaCl solution from -10 C to +18 C (1,5 hours) Specimens after 20 test cycle IV. ABRASION RESISTANCE TEST V. ADHESION TEST Concrete with coatings Concrete without coatings 0,54 g/sq. sm 0,91 g/sq. sm Adhesion to wet concrete = 2,8 MPa Adhesion to dry concrete = 3,2 MPa Cohesion concrete destruction
3. BRIDGE DECKS Steel and concrete bridge deck waterproofing Asphalt pavement
Bridge deck waterproofing. Overview To increase the durability the bridge decks have to be waterproofed. Due to dynamic loading, the bridge decks must be protected with elastic crack-bridging systems which are able to accommodate every movement. The whole system shall be able to withstand the traffic load for which the bridge is designed. In addition bridge deck waterproofing system must provide a good bond to the asphalt pavement. Requirements for Waterproofing Systems: Impermeable to water; Extended service life of 50 to 100 years; Good adhesion to deck / substrate; Capable of bridging cracks in the concrete deck or opening of joints between adjacent precast members; Easy and quick application under different weather condition; Able to carry load after 1 hour; Easily repairable; Bond to different types of asphalt pavements. Types of waterproofing Systems Sheet systems Liquid systems
Bridge deck waterproofing. Sheet waterproofing system problem Blistering and cracking Slowness of Application Joint Failures Poor Detailing Puncturing Low durability Poor Adhesion To Deck Poor Adhesion to Surface Materials
Bridge deck waterproofing. Welesgard liquid spray applied system WG-Welestrong AP is a 100% solids two-component, bridge-grade elastomeric polyurea coating used to waterproof both steel and concrete bridge decks. WG-Welestrong AP provides a seamless, flexible, extremely durable barrier against water penetration and stray current. Processing of spray polyurea requires specialized, high pressure and high temperature plural spray equipment. Graco Reactor EX-P II WIWA-Airless DUOMIX PU 460 Area of Application: WG-Welestrong AP membrane is specifically engineered for use on highway and railroad bridge decks, bridge abutments, pier caps, tunnels and pedestrian walkways. WG-Welestrong AP membrane can be used on intermodal and LRT rail bridges with or without protection board, providing fast turnaround for demanding schedules.
Bridge deck waterproofing. WG-Welestrong AP properties Properties WG-Welestrong AP Color: UV resistance: Temperature stability: Tensile strength: Grey Normal In temperature from -60 C till +220 C (short-term till +260 C) not less 20 МPа Elongation: not less 350% Adhesion Concrete: Steel : Hardness (Shore A) 96% Abrasion resistance 100 cycles 1000g wheel H-18: Curing time Gel: Tack free: 2,5 N/sq.mm 4,0 N/sq.mm 150 g 15 sec 40-60 sec
Bridge deck waterproofing. WG-Welestrong AP Crack Bridging Elongation > 350% Tensile Strength > 20% Tensile Strength > Bond To Deck
Bridge deck waterproofing. WG-Welestrong AP key benefits + Fast Cure, and as a result: a) One-coat system with layer thickness of several millimeters is cured within several seconds b) Can be sprayed on sloped (and even vertical) surfaces without drip or run formation c) Foot traffic can resume on coatings applied to horizontal surfaces within 30 seconds + Can be applied under high relative air humidity (till 98%) and low temperatures (till -15 С) + Excellent waterproofing and anti-corrosion properties + High chemical resistance + Excellent physical properties, including tensile strength, tear strength and elongation + High temperature stability (from -60 C till +220 C, short-term till +260 C) + Excellent adhesion to clean substrates such as concrete, wood, asphalt and fresh blasted steel + 100 % solids. Environmentally friendly + Reinforcible fibers and fillers can be incorporated during application
Bridge deck waterproofing. WG-Welestrong AP systems different types of asphalt pavement WG-Welestrong AP Adhesive polyurea waterproofing membrane WG-Welestrong AP WG-Welestrong Sealer WG-Welestrong Primer properly prepared concrete bridge deck properly prepared steel bridge deck
Bridge deck waterproofing. WG-Welestrong sealers, primers and adhesives WG-Welestrong Primer is used on steel surfaces to enhance the bond between polyurea waterproofing membrane and the substrate WG-Welestrong Sealer is used to seal porous surfaces, such as concrete, cement, brickwork and other mineral absorbing surfaces, and improve the adhesion of subsequent polyurea waterproofing membrane WG-Welestrong AP Adhesive is used as adhesive layer between polyurea waterproofing membrane and road surfaces from different types of asphalt pavement (macadam mastic asphalt concrete, rolled and poured asphalt, gussasphalt) WG- Welestrong Contact is used as adhesive layer between old and new polyurea coatings
Asphalt pavement. High-performance solution WG-Welestrong AP Membrane + Gussasphalt Reliability for decades
Asphalt pavement. Gussasphalt performance Gussasphalt ( 2 layers x 40 mm) WG-Welestrong AP Adhesive polyurea waterproofing membrane WG-Welestrong AP WG-Welestrong Sealer or WG-Welestrong Primer properly prepared concrete or steel bridge deck
Asphalt pavement. Gussasphalt performance Water on the surface of the Gussasphalt Gussasphalt is waterproof Waterproofing membrane Gussasphalt is waterproof
Asphalt pavement. Gussasphalt performance Loads in Asphalt pavement Wear layer Base layer Waterproofing membrane
0 5 10 15 20 25 30 35 40 45 50 55 60 Cost, % 0 5 10 15 20 25 30 35 40 45 50 55 60 Cost, % 0 5 10 15 20 25 30 35 40 45 50 55 60 Cost, % Asphalt pavement. Gussasphalt performance Gussasphalt S K = 1.00 100 75 50 25 0 Major maintenance after 30 years Time, years 100 75 50 25 Hot -rolled Asphalt S K = 1.26 0 Major maintenance after 20 years Concrete Asphalt S K = 1.45 Time, years 100 75 50 25 0 Major maintenance after 15 years Time, years
Waterproofing and Asphalt pavement. International standards BD 47/99 Waterproofing and surfacing of concrete bridge decks. ASTM D6153-97(2007) Standard Specification for Materials for Bridge Deck Waterproofing Membrane Systems SIA 281/3 Bitumenbahnen Haftzugprüfung BD 47/99 requirements
Waterproofing and Asphalt pavement. Test specimens
Waterproofing and Asphalt pavement. Shear bond test
Waterproofing and Asphalt pavement. Surface preparation Steel bridge deck Concrete bridge deck 1 machine: 500 sq. m per day 2 machine: 1000 sq. m per day 1 machine: 750 sq. m per day 2 machine: 1500 sq. m per day
Waterproofing and Asphalt pavement. Waterproofing application 1 st layer WG-Welestrong Sealer at concrete bridge deck WG-Welestrong Primer at steel bridge deck
Waterproofing and Asphalt pavement. Waterproofing application 2 nd layer WG-Welestrong AP membrane application
Waterproofing and Asphalt pavement. Waterproofing application 3 rd layer WG-Welestrong AP Adhesive
Waterproofing and Asphalt pavement. Gussasphalt application 1 st layer
Waterproofing and Asphalt pavement. Gussasphalt application 2 nd layer