Integral brides in basic words can be characterized as extension bridges without joints. Basic bridges are portrayed by solid association between the deck and the substructure (piers and projections). They traverse from one projection, over middle of the road support to the next projection, with no joint in the deck. Necessary extensions have been built everywhere throughout the world including India.
What is meant by Integral Bridge?
The types of bridges built without any extension joint (either between spans or between spans and abutments) and exclusive of any postures are known as integral bridges.
Features of Integral Bridges
The concept of integral abutment bridge is dependent on the theory that because of the elasticity of the piling, thermal stresses are shifted to the foundation by way of a stiff association amid the superstructure and the substructure
Reasons Behind Integral Bridges
- To dispose development joints in the deck
- When quake powers are transcendent or when thought like expanded imperviousness to impacts the vital scaffold idea is a great choice.
- Less costly
- Improved sturdiness
- Easy to plan
Why Integral Bridges?
The expansion joints and bearings, by virtue of their functions are sources of weakness in the bridge and there are many instances of distress in bridges, mainly due to poor performance of these two rudiments.
Complications of Expansion Joints and Bearings
- Leaking of extension joints and closes allow the surface run water from roadway
- Continual wear and overwhelming effect from rehashed live loads and additionally ceaseless phases of development from extension and constriction
- Impact loadings from overwhelming business vehicles
- Elastomeric direction can part and crack because of unforeseen developments, or ratchet out of position.
- Malfunctioning of course can prompt to unforeseen basic harm
- Joints and bearings are costly
Integral Abutment
The integral abutment is known as abutment, which is linked to the bridge deck exclusive of any movement joint for extension or retrenchment of the deck
Why Integral Abutments:
- Basic Design
- Joint less development
- Imperviousness to weight
- Fast development
- Ease in developing banks
- No cofferdams
- Vertical heaps (no battered heaps)
- Basic structures
- Few development joints
- Lessened expulsion of existing components
- Basic bar seats
- Rearranged enlarging and substitution
- Bring down development expenses and future upkeep costs
- Enhanced ride quality
- It Design productivity
- Included excess and limit with regards to calamitous occasions
- Enhance Load conveyance
- Improve insurance for weathering steel girders
Planning Consideration
- Length of the Structure
- Climatic Condition
- Seismic Zone
- Sort of Superstructure
- Sort of Abutments
- Sort of Foundations And Sub-Soil Conditions
- Geometry of the Structure
Quality improvement practices recommended for integral bridges:
- Multifaceted nature in Analysis and Design
- Suggested Quality Improvement Practice for Integrated Bridges
- Create plan criteria or office hones for outlining indispensable projection and join less scaffolds
- In augmenting the rest of the administration lives of existing scaffolds
- Trade data in the regions of outline, development and support of joints and joint less extensions
- The choice to introduce an approach chunk ought to be made by the Bridges and Structures Office, with interview from the Geotechnical gather
- Standardize routine of utilizing sleeper pieces toward the end of all approach sections
Benefits of Integral Bridges over Conventional Bridges
- Rearranged points of interest for development
- Decreased life cycle cost and long haul support
- Enhanced plan productivity Improved riding quality
- Included excess without breaking a sweat in developing dikes
- Disposal of water spillage on basic components
- Lesser resistance limitation because of end of course and extension joints
- Speedier development
- Disentangled extending and substitution detail
Examples of Integral Bridges:
- Dankuni-Palsit Flyover
- It is located in the Durgapur Expressway.The span agreement for the bridge is 15m + 2×22.0 m + 15m, constant over the support. The deck is RC solid slab type fundamental with the twin piers. The bridge is a joint less bridge exclusive of any expansion joint over transitional piers without any bearings.