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Correct procedure for the installation of Bridge Expansion Joints

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  • Types Of Expansion Joints

  • How Expansion Joints Manufacture

  • Installation Procedure Of Strip Seal & Modular Expansion Joints

  • Defects In Expansion Joints

  • Precaution To Be Taken At Site During & After Installation Of Joints

Type of Expansion Joint

Movement (Not Gap)

Popularity

Buried Expansion joint

Upto 10mm

Only for small bridges

Filler Expansion joint

Upto 10mm

Only for small bridges

Asphaltic Plug Expansion Joint

Upto 25mm

Only for small bridge rehabilitation work

Compression seal Expansion joint

Upto 40mm

Shorter life of upto 10years

Slab seal

Upto 80mm

Liable for excessive wear and tear

Strip seal expansion joints

Upto 80mm

Upto 25years , easy to replace seal

Modular Expansion Joints

Each module can take 80mm (above 80 to 2000mm)

Upto 25years , easy to replace seal

Finger Expansion Joint

Above 80mm

Upto 25year, vegetation is openings ,lot of noise,  require regular maintenance

Installation of  Single strip seal Expansion Joint & Modular Expansion Joint

 

Components Of Strip Seal Expansion Joint

STRIP SEAL EXPANSION JOINT T-TYPE LOOP & PLATE, Bridge Expansion Joints DECG

 

Connecting With Splice Plate

 

 

 

 

Components Of Modular Expansion Joint

Modular Expansion Joints

 

Connecting With Splice Plate

 

 

Preparation of the recess/block-out

 

BLOCK-OUT FOR STRIP SEAL EXPANSION JOINT

BLOCK-OUT FOR STRIP SEAL EXPANSION JOINT

BLOCK-OUT FOR MODULAR EXPANSION JOINT

BLOCK-OUT FOR MODULAR EXPANSION JOINT

a) The dimension of block-out  for strip seal must be 650 mm wide & 300 mm

b) The width of block-out for modular joint must be 1100 mm for 2 seal, increase width by 150 mm for every additional seal .Example for 4 seal modular joint the block-out will be 1400 mm.

c) The minimum depth of block-out must be 400 mm better till bottom shuttering .

d) Check the existing structural reinforcement according to the drawings. If it is less add extra reinforcements

1.It is recommended to lay the road surfacing/wearing coat before commencing installation of joint.

2.The Steel Plate / Shuttering / Wood to be used to seal the space between the underside of the joint face of the recess

3.The recess portion shall be filled with sand bag.

Steel Plate for Strip seal expansion joint

Steel Plate for Strip seal expansion joint

 

 

Shuttering for Modular Expansion Joint

Shuttering for Modular Expansion Joint

Filling Sand Bags For Strip Seal Expansion Joint

Filling Sand Bags For Strip Seal Expansion Joint

 

 

Filling Sand Bags For Modular Expansion Joint

Filling Sand Bags For Modular Expansion Joint

 

 

The recess shall be cleaned thoroughly. If necessary, the surface should be roughened. All loose dirt and debris shall be removed by wire brushing, air blowing and dried with hot compressed air or manually if no facility available at site but cleaning must be done thoroughly.

The recess must be thoroughly watered

The recess must be thoroughly watered

Air Blowing

Air Blowing

Clear Block-Out After Cleaning For Strip Seal Expansion Joint

Clear Block-Out After Cleaning For Strip Seal Expansion Joint

Clear Block-Out After Cleaning For Modular Expansion Joint

Clear Block-Out After Cleaning For Modular Expansion Joint

Placing in the recess/block-out

Before placing of expansion joint in the recess, all segments must be joined together at the splicing location provided at the end of the segments by welding / all spice plate but be weld from all sides , no spice plate cut at site.

 

Connecting Segments & Adjusting Gap for Strip Seal Expansion Joint

Connecting Segments & Adjusting Gap for Strip Seal Expansion Joint

Connecting Segments & Adjusting Gap for Modular Expansion Joint

Connecting Segments & Adjusting Gap for Modular Expansion Joint

 

The gap between edge beams / edge and middle beam shall be adjusted at site based on the temperature

Complete Segment Length of Strip Seal Expansion Joint

Complete Segment Length of Strip Seal Expansion Joint

Complete Segment Length of Modular Expansion Joint

 

Lowering the expansion joint into the recess should be done in such a way that the entire length of the joint is evenly lowered into the recess. Thereafter, the

Leveling The Expansion Jointjoint is precisely leveled and adjusted in the longitudinal, transverse and vertical planes.

If required, the joint must also be adjusted to the gradient of the final surface level. As soon as the joint is accurately placed, the engineer in charge shall provide a written confirmation of the correct placement of the same.

Connecting

The preliminary fixing is made by evenly placing then welding of rebars over the entire length between the anchorage and the deck reinforcement.

Connecting Expansion Joint with main Reinforcement

Connecting Expansion Joint With Main Reinforcement

Connected Strip Seal Expansion Joint with main reinforcement

Connected Strip Seal Expansion Joint with Main Reinforcement

Connected Modular Expansion Joint With Main Reinforcement

Concreting

Concreting

 

 

 

 

 

  • Prior to final concreting, the position of the expansion joint must be recorded.
  • Before pouring the concrete the joint construction should be protected by a cover.

Picture1

Form-Work & Covering of Strip Seal Expansion Joint

Form-Work & Covering of Strip Seal Expansion Joint

Form-Work & Covering of Modular Expansion Joint

Form-Work & Covering of Modular Expansion Joint

  • Controlled concrete having strength  ≥  maximum of  ( that in superstructure , M 35) shall be filled into the recess.
  • The water cement ratio ≤ 0.4 & if required admixtures may be used to improve work-ability.

Concreting

conc2

 

 

 

Removing Clamp after 12 to 24 h of Concreting for Strip Seal Expansion Joint

Removing Clamp

Removing Clamp after 12 to 24h of  Concreting for Modular Expansion Joint

Removing Clamp after 12 to 24h of Concreting for Modular Expansion Joint

The filling concrete must

  • Good compaction (properly vibrated)
  • proper curing at-lest 28 days.
  • Don not allow vehicle to move over Expansion joints till curing period of 28 days over , even with any temporary arrangement like putting plates, sandbags etc.

Installation of Neoprene seal

Installing Elastomeric Seal

Installing Elastomeric Seal

 

 

Installing Elastomeric Seal

Installing Elastomeric Seal

 

 

 

 

Don’t join the strip seal

 

Installing Elastomeric Seal

 

 

 

Final Installation of Strip Seal Expansion Joint

Final Installation of Strip Seal Expansion Joint

 

 

Final Installation of Modular Expansion Joint

Final Installation of Modular

 

FAILURE OF EXPANSION JOINTS : REASONS

Reason The joints was installed before laying of wearing coat There is difference in level of edge beam Splice plates not welded at all Lack of curing

Reason

The joints was installed before laying of wearing coat There is difference in level of edge beam Splice plates not welded at all Lack of curing

 

 

Reason Expansion joint failed due to heavy traffic movement

 

Reason

Expansion joint failed due to heavy traffic movement

 

 

Reason Lack of curing The traffic started before complete period of curing

Reason

Expansion joint failed due to vegetation in openings

 

 

Reason Expansion joint failed due to vegetation in openings

Reason

Vegetation there is no traffic movement area

 

 

 

Vegetation there is no traffic movement area

Reason

Vegetation there is no traffic movement area

 

 

 

PRECAUTION TO BE TAKEN AT SITE DURING & AFTER INSTALLATION OF JOINTS

QUALITY CHECKS & Precaution SITE
BASIC QUALITY CHECK before buying Expansion Joints
  • Buy expansion joints from Reputed company only who is having full fledge production and testing facilities, shot blasting is must before primer and painting in factory.
  • The manufacturing must have all type of testing facilities mentioned in IRC specifications SP 69:2011.
  • Check at least 20% Quantity of Edge Beam of expansion Joint without primer & paint at factory so that it can be check whether manufacturer giving Monolithic Edge Beam for strip seal expansion joints
  • Check thickness of paint

Precaution to be taken at site During installation

  • The joints must be kept at least 6inch (150mm) on wooden planks above floor level and under shed till start of installation.
  • The welding rod must of reputed company like Esab , Modi etc , do not use local made welding rod for fabrication at site Expansion joint with deck reinforcement.
  • The expansion joint installation must be under supervision of manufacturer at least 50% Quantity.
  • The concrete must of at least M30 or higher grade, and must be compacted properly.

Precaution to be taken at site After installation

  • The expansion must be cure for at least 28 days
  • No vehicle shall be allowed to run over joints including small trolley for 28Days.
  • The elastomeric strip seal can be install after 48 hours of concreting , and curing must be continue for 28 days.
DECG InternationalCorrect procedure for the installation of Bridge Expansion Joints
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What is the purpose of bridge bearing

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A bridge bearing is a part of a bridge which typically supply a resting surface between bridge piers and the bridge deck.

The main purpose of a bridge bearing is to authorize controlled movement and accordingly reduce the stresses combine. Possible causes of movement are thermal expansion and contraction, creep, shrinkage, or fatigue due to the assets of the material used for the bearing. External sources of movement include the agreement of the ground below, thermal expansion, and seismic activity.

There are various different types of bridge bearings which are used depending on a number of unlike factors including the bridge span, loading conditions, and achievement specifications.

The elderly form of bridge bearing is simply two plates resting on top of each other. A general form of modern bridge bearing is the elastomeric bridge bearing. Additional type of bridge bearing is the mechanical bridge bearing. There are various types of mechanical bridge bearing, such as the pinned bearing, which in turn includes specific types such as the rocker bearing, and the roller bearing. Different type of mechanical bearing is the fixed bearing, which allows rotation, but not other forms of movement.

Types of bridge bearing

Steel bearings (flat bearings, curved bearings, rocker bearings, and roller bearings): Forces through steel contact surfaces. Bearing displacement is specially achieved by rolling steel and steel.

PTFE bearing (sliding bearing): The seat adopts PTFE and steel plate as the relative sliding surface of the bearing, and the sliding friction coefficient is much smaller than that of steel and steel.

Rubber bearings (plate rubber bearings, basin rubber bearings, PTFE plate-type rubber seats): The bearing force is achieved by a rubber plate. The movement of the carrier is achieved by sliding of PTFE or the shearing of rubber, and the supporting angle is deformed by the compression of rubber.

Concrete bearings (concrete hinge seats). Lead support: The strength part is composed of hard lead. As per to the structure of the bearing type, it can be normally divided into curved bearings, rock shaft bearings, roller bearings, plate rubber bearings, PTFE plate rubber bearings, basin rubber bearings, spherical bearings and so on. The bearings will be described separately below. Bearings are structural part that withstand high stresses. The load of the superstructure is concentrated in very small areas by the bearings. The reaction force of the roller bearing passes the linear contact force linking the roller and the rolling surface, and the force flow construct a significant stress consolidation phenomenon, which makes the contact surface bear high contact stress. And plate rubber bearings, tank rubber bearings, and spherical bearings and other bearings transmit reaction force, through the plane to the plane, the transmission is smooth, no strong flow necking phenomenon, which is a more reasonable power mode.

 

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    Use of expansion joint in building

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    Expansion joint is very essential in building to reduce the cracks because of thermal variation. Bureau of Indian standard fixed the some length of buildings above which the one or more expansion joint is required in building.

    Expansion joint is very essential in building to reduce the cracks because of thermal variation. Bureau of Indian standard fixed the some length of buildings above which the one or more expansion joint is required in building.An expansion joint is provided in concrete to authorize the movement of structural elements due to temperature, moisture & other changes.

    It recognize concrete structure to expand or contract due to thermal variation without causing stress, which can lead to reduce the cracking in a building.

    Expansion joints break the long concrete structure in separate parts that help to prevent the transformation of earthquakes vibration on other parts of buildings.

    If an earthquake occurs, the long structure act as a two or more dissimilar structure due to expansion joints.

    It is also known as movement joints, can be use not only in buildings but also in bridges, sidewalks, railway tracks, piping systems, ships, and other structures. Expansion joints can be incorporated into various building parts to supply complete separation like floors, ceilings, walls, roofs, and facades. They can be placed floor-to-floor, floor-to-wall, wall-to-wall, ceiling-to-ceiling, ceiling-to-wall, roof-to-roof, or roof-to-wall.

    It may serve more than one “joint” purpose at the same time. Generally, these joints isolate a frame into a series of segments with sufficient joint width to allow the building’s thermal expansion. By isolating the segments, expansion joints also recognize relief from cracking due to contraction and therefore act in a dual role an expansion and a contraction joint.

    Where are expansion joints required?

     

    Expansion joints are awaited to fulfill certain criteria like:

    Having high load-carrying volume (e.g. vehicle wheels load)
    Water tightness in the joint and its link at each side to prevent leaking.
    Suitability for pedestrian traffic (e.g. with high-heeled shoes)
    Resistance to aggressive substances
    Reducing vibrations in provision where delicate goods are being transported (e.g. in glass factories)
    Should be eye-pleasing.
    Types of Joints
    Interior Floor Joints
    Exterior Floor Joints
    Interior Wall/Column Celing & Exterior Wall
    Parking Joints

     

     

    Architectural expansion joints recommended in:
    Commercial Buildings , Residential Buildings.
    Hotels, Hospital, Institutional Building, Offices.
    Educational buildings.
    Airports.
    Metro stations & Railway stations.
    Parking, Podium structures.
    Stadium.

     

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      DECG InternationalUse of expansion joint in building
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      Types of Bridge Bearings and their Details

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      Bridge bearings are structure equipment or devices that are installed between bridge substructures or superstructures. The bearings are used to transfer the applied load on the bridge, including earthquake load, wind load, traffic load, etc. Bridge bearings are also responsible for the relative movements between the superstructure and substructure. For example, rotation and translational movements in horizontal or transverse directions.

      Bearings used in constructing bridges are divided into two major categories – expansion bearing and fixed bearing. While the expansion bearings can permit translational and rotational movements, the latter only allows rotational and some translational movements. DECG International is one of India’s best bridge bearing manufacturers that offer all the various types of bridge bearings and also guarantee high quality.

      Types of Bridge Bearing

       The different types of bridge bearings and their uses in various constructional areas are as follows:

      Pot Bearings:

      pot ptfe bearing manufacturer in india

      A bearing consisting of a metal piston supported by a disc of unreinforced elastomer that is confined within a metal cylinder for allowing rotational movement about any axis in horizontal plane and to bear and transmit vertical load. Pot bearings may be provided with sliding assembly (with or without restraint in the form of guide along a desired direction to bear and

      transmit horizontal force) comprising of stainless steel plate attached to metal backing plate sliding in horizontal plane over sliding material confined in recess(s) on the piston which shall be termed as Sliding / Guided Pot bearings. Depending on the desired degree of freedom Pot bearings may be of three types as follows:

      1. Fixed Pot Bearing
      2. Sliding Pot Bearing
      3. Guided Pot Bearing

      Rocker and Pin Bearings

      Rocker is an expansion bridge bearing that is composed of a curved surface at the bottom that can accommodate the translational movement and a pin on the top that facilitates the rotational movement of the bridge structures.

      Rocker and Pin bridge bearings are used in steel bridge structures and are considered when the bridge movement is known and described adequately. These bridge bearings can undergo severe corrosion and deterioration, making regular inspections and maintenance an essential part of the construction.

      Pin Bearing Manufacturer In India

      Roller Bearings

       

      ROLLER-CUM-ROCKER BEARING MARKING DECG

      Roller bearings are used to construct concrete or steel bridge structures. The roller bearing can be used in two different forms, namely – single roller and multiple roller bearings. Multiple roller bearings have several rollers installed under the two plates and can facilitate both rotational and translational motion for the bridge. One of the best things about roller bearings is that they are cheap to manufacture, but they have a limited weight capacity, making them suitable for specific constructions. On the other hand, multiple roller bearings are expensive and can short large vertical loads. These rollers need regular inspections and rehabilitation since they are susceptible to corrosion and damages.

      Elastomeric bearings

      Elastomeric bearings are elastomers manufactured from synthetic and natural rubber. These bridge bearings support both translational and rotational movements through elastomer deformation. Elastomeric bearings can carry large loads and prevent lateral bulging of the elastomers.

       

      Elastomeric Bearing Manufacturer in Indian

      The number of elastomer pads needed for the construction depends on the type of reinforcement used for the bridge. For instance, steel reinforces elastomeric bearings are the strongest, and plain elastomeric pads are the weakest. One of the best things about Elastomeric bridge bearings is that they are neither expensive nor require any maintenance after installation.

      Spherical Bearings:

      The Spherical bearings consists of a pair of matching concave and convex steel spherical backing plates with a low friction sliding interface in between them permitting the rotation by in-curve sliding. For the purpose of providing the translation

      Ability, bearings are combined with the flat sliding elements. Depending on the desired degree of freedom Spherical bearings may be of three types as follows:

      1. Fixed Spherical Bearing
      2. Sliding Spherical Bearing
      3. Guided Spherical Bearing

      Wrapping Up!

      DECG International is one of the best bridge bearing manufacturers in India. We ensure the proper manufacturing of the highest quality bridge bearings for all construction needs. We have an excellent infrastructure that helps us provide the best quality construction products to all our clients.

      Reference Sources:

      Civildigital

      Constructor

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        Why Expansion joints are Important for Bridges?

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        Expansion joints are widely used during the construction of bridges. They are the component which is essential for the life of a bridge. Thus, they must be properly installed and maintained to function properly. The bridge expansion joints efficiently help with the movement and rotations of the superstructure of the bridge. When installed properly, only a small section of the complicated construction is visible.

        The bridges face a lot of challenges and stress. To handle such mechanical stress, expansion joints are used. But this comes to the challenge of corrosion and other environmental factors which can degrade the bridge expansion joints. It can be prevented by the use of robust hot-dip galvanizing.

        Numerous countries worldwide are making use of bridge expansion joints to provide adequate support and help to the bridges. Given the demand finding a reliable expansion joint manufacturer in India isn’t difficult. Given the importance of the expansion joints, you must know about the types and the factors to consider you need to know before purchasing them.

        Why are bridge expansion joints important?

        It is the proper installation and maintenance of the bridge which leads to failure. When the bridges do not have expansion joints installed, they lack adequate flexibility and smooth movement. Further, the structure can collapse, leading to great damage. Thus, it is essential to use bridge expansion joints during the bridge construction. Here’s why they are essential.

        • Helps a bridge in expansion and contraction based on the temperature change.
        • Offers protection that holds up the bridge
        • Help protect the concrete structures present underneath the joints
        • Use of high-quality bridge expansion can offer cost-saving results
        • Helps with the contraction and expansion due to thermal cycle
        • Protects the concrete structures from damage due to vehicle traffic
        • Helps in the natural shrinkage and concrete creep

        Given the important use of expansion joints, you must make a purchase from a reputable manufacturer as this will guarantee quality and safety.

        What are the types of expansion joints?

        The expansion joints are widely used to hold the parts together while safely tolerating the temperature expansion and contraction of the structure. They are designed to allow continuous traffic flow between structures while efficiently accommodating shrinkage, temperature movement, and other forces. It is the expansion joints that prevent the bridges from bending out due to extreme conditions. One can now easily find a number of expansion joints for various purposes. However, there are two most essential types of expansion joints, which include.

        • Open joints

        These bridge expansion joints allow the free flow of water and debris through the joint. They lead to debris build-up, which makes them an inefficient choice. Here’s the top open joint used for bridges.

        Finger joints

        Sliding plane joints

        Butt joints

        • Close joints

        These bridge expansion joints are efficient enough to prevent the movement of water and debris from penetrating inside. However, they must be designed specifically to enhance the movement and properties of the intended joint. Here’s the top close joint used for bridges.

        Compression seal

        Stripe seal

        Poured joints

        Asphalt plug joints

        Reinforced elastomeric joints

        Modular elastomeric joints

        Important factors to consider

        When using concrete as a building material, there are numerous things you need to consider. The most important of all is the weight and strength of the concrete. But besides this, there is another factor, i.e., the effect of the environment on the material. Thus, you need to consider the thermal cycles of the geographical area to ensure you choose the right expansion joint that will offer intended results.

        With the changes in the season and temperature, the structure can greatly be affected. Thus, during such times when the structure expands or contracts, it can take a toll on the joint expansion system.

        Besides this, the heating and cooling cycle of the structure can also lead to expansion and contraction. When the contraction is greater than the tensile strength, of the material then there is a great chance of crack. In contrast, when the expansion is restricted, then the material can crush or distort. Thus, to prevent such failures, you must ensure to fit the concrete bridges with a good material that allows for proper expansion and contraction without causing any damage to the structural integrity.

        However, there are a number of options available. Thus, choosing the best one can be difficult for your requirement. You must consider all the factors as it will help you make the best decision. Further, you need to purchase a good expansion joint manufacturer in India. This will help guarantee you get quality products. Also, they can advise you about the use of the right type of expansion joint for your specific purpose.

        Further, remember each of the compression joints has its specific application method and other parameters that must be followed to ensure proper application and results. It is the accurate sizing of the joints and the accurate assessment of the movement of the structure that must be considered before selecting a bridge expansion joint. Further, it is also essential to consider various other factors like manufacturers’ requirements, climatic factors, preparation plan, physical properties, and joint material limitations.

        Contact a good bridge expansion, joint manufacturer.

        The expansion joints will work to the best only when adequately installed and of high quality. It is the quality of the joints which guarantees smooth and efficient movement. Thus, it is essential that you contact a good bridge expansion joint manufacturer in India to make your purchase. DECG International is among the leading manufacturers who can offer you a guarantee of quality at a fair rate. We have been manufacturing components that help in the construction of bridges and other structures. We can help you get the best expansion joints that fit your requirement. The pricing of all our structures is kept at an affordable rate, meaning you need not have to worry about the cost of your purchase with us. So wait not in contact our company today to get the best bridge expansion joints.

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