Pratap Singh Rautela, Nile Waterproofing Materials, Co. S.A.E. company Noida.

Bridges are important infrastructure facilities connecting different areas and allowing smooth movement of men, material and machinery from one place to another. Roads have no purpose unless bridges are provided for crossing rivers. Railway lines (ROB), highways (Flyovers) etc. Early deterioration of cement concrete bridge structures resulting into weakness or even part collapses disturb the movement of traffic and has serious impact over social and financial status of the local society. Minor causes like leakage and seepage of water or deicing salt solution into even the slightly permeable deck concrete surface result into corrosion of reinforcing steel which result into spalling, cracking and loss of section of structure.

The problem can be solved to a great extent if concrete surface is protected against ingress of moisture and salts. In other words, if a protection layer is introduced over the bridge deck concrete surface in form of a dependable water proofing system.

Bridge Decks: Waterproofing Choice

waterproofing latest technique
The waterproofing of bridge decks is recognized in many European countries as a vital and necessary operation to enhance the durability and longevity of the life of bridge.

It represents the first line of defense and prevents the ingress of water, road de-icing salts, and aggressive chemicals which would corrode the steel reinforcing bars in the concrete causing severe structural damages.

Some countries with mainly warm weather and dry climates choose not to waterproof their bridge decks but, a recent analysis in the USA showed that 200,000 Bridge decks are seriously suffering from corrosion resulting in direct cost of $2 billion for replacement and refurbishment.

Concrete will always have some degree of porosity and allied with surface wear and hair line cracking, will allow water and corrosive materials to penetrate and attack the steel reinforcement. The primary defense against such destructive agents is good dense concrete, along with a proven waterproofing system installed by a qualified contractor.

Bridge Deck Waterproofing Systems

Two types of Bridge deck waterproofing systems are available for use:
  1. Sheet Systems These are Polymer Modified Bituminous sheets bonded to the bridge deck, using torch application, hot mopping asphalt, or through self-adhesion. Manufacturers have developed various systems that would satisfy the enhanced requirements of the bridge deck waterproofing market.
  2. Liquid (Sprayed) Systems These systems largely fall into acrylics and Polyurethanes and normally consist of three elements. Primer, Membrane applied in one or two coats and tack coat specially developed to enhance the bond of the membrane to the surfacing mix.

Performance Requirements for the System

Independent of the bridge deck waterproofing system choice, certain performance criteria has to be met in order to avoid potential concerns regarding leakage, poor bonding, embrittlement or softening of the membrane in service.

Such performance criteria are:
  • Impermeability to water under all conditions
  • Good adhesion to deck
  • Good adhesion to surfacing.
  • Capable of bridging shrinkage cracks in concrete
  • High mechanical properties to handle traffic loads including shear forces in curves and during braking and accelerating
  • Tolerant of deck texture and details
  • Tough to withstand site damage and operation
  • Safe to apply
  • Able to withstand elevated surface temperatures
  • Can be applied over a wide range o f ambient conditions
  • Nonegradable

Proper Site Practice the key Success

The success of bridge deck waterproofing operation is often reliant on site procedures, workmanship and weather conditions.
  • Professional preparation is as important as the properties of material or system to be used. Before the work commences at site the following major issues need be addressed:
  • Availability of properly trained workforce and qualified supervisors
  • Site engineer must have design detailing and construction records accessible
  • Provision of adequate strong area for material to be used
  • A Safe access to bridge deck must be secured for personnel, equipment and materials
  • Established method of statement, and execution program discussed and approved by all parties
  • Review of weather conditions likely to affect the waterproofing operation
  • Preparation of concrete deck to meet strict surface finish requirements (Sound, even, uncontaminated, dry, dust free). Thereby offering optimum opportunity for a strong bond to waterproofing membrane.
  • Use of an appropriate primer
  • Choice and application of a waterproofing system approved and in compliance with Highway Agency Standards.
  • Adequate protection of the waterproofing membrane prior to the application of the asphalt road surfacing
  • Use of approved asphalt road surfacing with low void content mix design

Bitunil Bridge Deck Waterproofing System

BITUNIL Bridge Deck Waterproofing System consists of two layers of fully torch welded heavy duty APP modified bitumen membranes with composite polyester reinforcement, applied on a primed substrate.

System Application:
  • Concrete surface must have a minimum acceptable gradient to ensure water drainage on the surface of the asphalt pavement.
  • A primer coat must be applied to concrete deck to seal the voids, promote W.P. adhesion, and assure against blister formation.
  • Prior to membrane application, a reinforcing MBM strip shall be applied to cover all intersections with edge beams.
  • Waterproofing Membrane shall be applied fully bonded to bridge deck, parallel to down slope direction. Side laps and end laps shall be 8-12 cm, and 12-15 cm respectively.
  • Second waterproofing layer shall be applied fully bonded onto the first layer, at the same direction of rolls length, with shifting the side laps 0.5 meter in order to secure the membrane waterproofing system with maximum overlaps.
  • Flashings must extend min. of 10 cm up against the edge beams.
  • Waterproofing must be protected against sunlight until asphalt layers, of drainage, protective and wear courses are applied. It is recommended to apply the asphalt layers as soon as possible.
  • Thickness and mix design of asphalt courses are as per consultant and project specifications.
  • Bridge deck joints must be filled up (Grouted) and covered with 200 mm
  • MBM cover strip prior to membrane application.
  • Bitunil System recommendation is for two layers of MBM fully torch welded onto deck surface however, for bridges with low daily traffic (ADT<2000), without significant importance to local and regional traffic, and without frequent breaking and turning traffic, a single layer system is adequately sufficient.
The wonder product from the Nile Waterproofing Materials Company S.A.E., BITUNIL, is the product of experience, prudence and knowledge. The Bitunil plant is built over an area of 20,000 square meters in Al Max Alexandria Port. The production plant is state-of the- art for manufacturing of modified bitumen membranes, and is fully equipped to manufacture quality products that comply with most of the internationally recognized standards.

Bitunil manufactures and market large types of waterproofing systems to suit different requirements of Engineering industry to mention few of those are BITUBOND–4, BITUBOND 4/E, NILOBIT-PM, NILOBIT-PM-MINERAL NILOBIT-F, BITY FLEX 4 & 4E, BITUPLAST 4 & 4/E, BITUGARDEN 4- 4E & M BITUTER 4 & 4E, BITUGUM MINERAL, NILOBIT-PN, NILOBIT-PM.

The company has achieved great reputation for its products and services it offers to its clients. The products are being used in almost all corners of the world due to their high quality, reliability, uniformity in Quality and successful performance.

Bridge Joints: Selection and Water Management

Based on the predicted movement related to imposed design loads, and temperature variation ranges, the bridge designer specifies the appropriate bridge joints. Selection can vary from a wide range of pre-fabricated expansion joints, to cast in place Asphaltic plug joints. The drainage system for the joint should ideally overlap the deck waterproofing system used. Combined subsurface drainage outlets serve to discharge water and prevent build-up behind the joint. Regular inspection of surfacing and joints is necessary to maintain satisfactory performance throughout bridge service life. Early fault detection, such as blocked drainage or damaged surfacing, is necessary to avoid major remedial work. Inspection and maintenance should be scheduled to coincide with other bridge maintenance work to reduce disruption and consequential costs.
Click Here
To Know More or to Contact the Manufacturer
Please let us know your name.
Invalid Input
Please let us know your Designation.
Please let us know your Contact Number.
Please let us know your email address.
Please brief your query.
Our other Value-Added Services:

To receive updates through e-mail on Products, New Technologies & Equipment, please select the Product Category(s) you are interested in and click 'Submit'. This will help you save time plus you will get the best price quotations from many manufacturers, which you can then evaluate and negotiate.

Invalid Input
Invalid Input
Invalid Input
Durability is a key requirement for modern infrastructure projects – highways and roads, bridges, airports and airfields, walkways and plazas, parking structures and stadiums. Miles of concrete must

Read more ...

Buildings have major environmental impacts over their entire life cycle. Resources such as ground cover, forests, water, and energy are depleted to give way to buildings. Today, India has demonstrated

Read more ...

Scour is a natural phenomenon caused by the erosive action of flowing stream on alluvial beds. Failure of bridge due to scour at their foundations, which in this case consisted of abutments and pier, one 1.2 dia

Read more ...

To protect concrete structures like Flyovers, Bridges, Parking areas, Big Commercial and Residential Buildings, the normal decorative exterior paint will not serve the purpose as these paints are not vapour permeable

Read more ...

Repair Strategy of Stoplog Sill Beams During Operation Stage of 510 MW Teesta-V Power Station in Sikkim Running Power Stations serve as a boom to the economy of the country and any generation loss due to construction

Read more ...

Concrete protective liner is a multipurpose solution for waterproofing and protection of concrete surfaces against corrosion and destruction. The product warranties long-term and reliable protection of structures

Read more ...

Sangeeta Pandey, Chief Manager (Civil), Power Grid Corporation of India Ltd., Patna, PVS Sudhakar, Sr. General Manager (Civil), NOFN Works, Power Grid Corporation of India Ltd., Vishakhapatnam & Dr. Achintya, Professor of Civil

Read more ...

Samir Surlaker, Director, Assess Build Chem Private Limited discusses some new joint treatments and injection systems in waterproofing. It is a myth that waterproofing treatments can be carried out by application of single material

Read more ...

Years of research plus decades of practical experience have enabled FAIRMATE to develop detailed solutions to restore and rehabilitate concrete structures with structural rehabilitation, retrofitting and strengthening of RCC structures

Read more ...

Sunny Surlaker, Head Technical Services, Assess Build Chem writes on the selection ideologies, materials and methods for defect remediation in Concrete Buildings. The building façade or the envelope is the primary line of

Read more ...

This article provides some basic information on effects of fire on concrete, various condition evaluation methods, and show findings from a case study of a fire exposed concrete foundation in California, and informs construction

Read more ...

There is considerable controversy within the concrete repair industry regarding the use of bonding agents as a pretreatment method for the repair of deteriorated concrete. This paper examines the use of bonding agents

Read more ...

This paper discusses the effects of fire on concrete and provides a methodology to assess, evaluate and repair concrete structures. Though concrete is among the best fire-resistant building materials, it does get damaged when

Read more ...

The ACI 562 Code Requirements for Assessment, Repair, and Rehabilitation of Concrete Structures and Commentary was first published in 2013 and revised in 2016. Development of ACI 562 was an industry response to variations

Read more ...

The repair industry in India and for that matter, throughout the world, is like the story of an elephant described by seven blind people. Whichever part of an elephant will come in the hands of a blind man, the elephant will be described

Read more ...

The Chamera Hydro-Electric Project (Stage-III) is located on the river Ravi at village Kharamukh (250.0 m downstream of the confluence of river Ravi and Tundah Nala) in Chamba district of Himachal Pradesh. The Project consists

Read more ...

Terex — a diversified global manufacturer of equipment for mining and quarrying industries — is celebrating 10 years of operations in India and has announced expansion plans for its 45-acre manufacturing plant in Hosur, with which it plans

Read more ...

The rapid boom in the construction industry, has tremendously given rise to the demand for sand, causing deficiency of suitable river sand in many parts of India. Besides, river mining causes imbalance in the river bed water flow, and

Read more ...

Regardless of the quality of pavement material and design, increase in vehicular traffic and changing environmental conditions will reduce the service life of pavements and ultimately result in their failure. The causes and

Read more ...

With the increase in construction of buildings in the last two decades, it has been observed that many of the structures are already showing signs of distress. In some cases, repair measures become necessary even within a span

Read more ...

×
Sign-up for Free Subscription
'India Construction Week'
Weekly e-Newsletter on Construction Industry
Get the latest news, product launches, projects announced / awarded, government policies, investments, and expert views.