3D Model of Rabindra Setu Howrah Bridge, India
Introduction to the CAD MODEL
This is a 3D scaled-down model of the Howrah Bridge which spans the Hooghly River, a distributary of the Ganges River that flows through West Bengal, India.
This 3D CAD model was created by CAD FM, a social enterprise based in Glasgow, and is available for 3D printing free of charge for educational purposes.
The 3D model was created using CAD software and will prove beneficial for adults or children interested in the construction or features of the Howrah Bridge or in understanding the uses and benefits of CAD modelling.
The CAD modelling software used depicts the features of the bridge in an authentic way and with maximum realism.
Please note that this model is available for educational purposes and that for any technical details of the bridge you should contact the relevant authorities.
3D Model Design
This 3D model of the Howrah Bridge India was made using CAD modelling software and neutral files are provided for 3D printing.
Features covered in model
This 3D CAD model of the Chaotianmen Bridge displays the famous lower and upper arches and clearly shows the principal structure of the road.
The internal lattice, another feature of what has become a landmark of Chongqing is also shown along with the two bases and the guy wires.
In designing this CAD model of the Howrah Bridge, the most difficult aspect was the internal lattice due to its delicate nature in the model form which belies its real strength.
The top beam was also challenging but the principal porticoes, bases and the road structure were relatively straightforward.
These aspects are large, solid blocks which are one of the simpler CAD modelling designs.
Available file formats
Here are available file formats
Tips for 3D printing
The smallest feature of the model measures 2 mm, which can easily be printed with any commercially available 3D printer. The complete model can be printed with very low infills.
The model is a single piece, it can be scaled and sliced to create a larger version. If you want to print at a larger scale then you should divide the model up into small individual pieces and print each piece separately.
In this way, the multiple pieces of the model are printed separately and then joined together with glue.
About the Howrah Bridge
The Howrah Bridge is a balanced cantilever bridge which spans the Hooghly River in Kolkata, West Bengal.
Balance cantilever bridges are constructed in segments to minimise load unbalance and rely on ‘negative bending’ to produce compression on the bottom side of a beam and tension on the top side to arch upwards.
Originally called the New Howrah Bridge, it was opened in 1943 and was renamed Rabindra Setu in 1965 in honour of the great Bengali poet Rabindranath Tagore, the first Indian and Asian Nobel Laureate.
Despite its official name change, it is still known colloquially as the Howrah Bridge. It is an iconic sight of Kolkata and West Bengal and is one of four bridges which cross the Hooghly River.
The Howrah Bridge is the sixth longest bridge of its kind in the world but is easily the busiest cantilever bridge anywhere on the planet and carries roughly 100,000 vehicles over the river every day.
The bridge contains no nuts and bolts and was put together entirely by riveting. It requires regular cleaning due to excessive spitting and bird droppings which would otherwise cause corrosion.
The Kolkata Port Trust spend Rs 500000 per year on cleaning costs alone!
History and Construction
Due to an increase in demand for crossing the Hooghly River, planners decided to replace the existing pontoon bridge in 1905 with something more substantial.
In 1906 the Port Committee decided a floating bridge should be built but following numerous interruptions to construction, including WW1, the floating bridge was never built.
When the original plans had been devised, the contract for constructing the bridge was almost given to a German company but they were refused due to growing political tensions between Germany and Britain.
The Braithwaite, Burn & Jessop Construction Co., a UK company was eventually awarded the construction contract in 1935. In 1939 when construction was once again due to begin on what was now called the New Howrah Bridge, war broke out again and all steel which had been intended for use on the bridge was rediverted to help the British war effort.
In the end just 3000 tonnes of the 26,500 required to complete the structure were supplied by Britain. When construction began, two anchorage caissons each measuring 16.4m by 8.2m, with two wells 4.9m square, were installed to aid with creating the foundations.
They included working chambers within the shafts which could be temporarily enclosed by steel diaphragms to allow work under compressed air if required.
The caisson on the Kolkata side was set at 31.41m with its opposite number on the Howrah side 26.53m below ground level.
One night during the process of grabbing the muck out, the ground shifted and the construction mass dropped around 6m registering as an earthquake on the seismograph and destroying a local Hindu temple which then had to be rebuilt.