Blog 2
Lambeth Bridge

Lambeth Bridge

Structure Information

The Lambeth Bridge was constructed in 1932 across the Thames River between Westminster and Lambeth. See Figure 1.

Figure 1: Lambeth Bridge Area

This connection was initially necessary because there was a house of the Archbishops of Canterbury at Lambeth that needed to be constantly connected to the King’s palace at Westminster [2]. Initially the Archbishop made the passage across the Thames by barge, then later by ferry. The church bought the ferry so the Archbishop and his goods and servants could travel across freely [2]. The Ferries were taken out during the civil war, so no intruders could pass the Thames this way, but later ferries were returned as a mode of transportation across the Thames [2]. Bridges were proposed as early as 1665. In 1750 the Westminster Bridge was put in very nearby, ending Lambeth Bridge proposals until 1809 [7]. The new Westminster Bridge also ceased the operation of the Archbishop’s Horseferrry, as it was in poor condition and now unnecessary [3]. From the 1809 Lambeth proposal, nothing happened until the Lambeth Bridge Act in 1861, for a toll bridge to be put up [4]. A suspension bridge was eventually selected and opened in 1862 as an 828 foot long, three-span bridge [2]. The old bridge can be seen in Figure 2.

Figure 2: Old Lambeth Bridge

Less than 20 years later, the first Lambeth Bridge was falling apart. The bridge was progressively closed to vehicles and later to people [3]. The current Lambeth Bridge was proposed but delayed by the 1914-1918 war [2]. In 1924, Engineer, Sir George W. Humphreys, and the architects, Sir Reginald Bloomfield and G. Topham Forrest, designed the bridge for King George V and Queen Mary [2&3]. The bridge cost about 80,000 pounds and was fabricated and put up by Dorman Long & Co Ltb in 1932 [4]. See the new bridge in Figure 3.

Figure 3: Lambeth Bridge

Historical Significance

            In 1932, the current Lambeth Bridge was opened, made of steel and pre-stressed concrete [3]. Steel caissons were used to make the piers [4]. This caisson technique along with other details of the construction and design process can be seen in the similar predecessor of the Lambeth Bridge, the Westminster Bridge. The Lambeth Bridge was a common bridge of its time. The bridge itself did not have any major innovations about it and, therefore, was not a model for the future.

In 1965, however, the Lambeth Bridge became the first bridge in London to be tunneled under, making it the first bridge in London that could be walked under [1]. This provided pedestrian access along the embankment, which was not available as it is today. This tunnel and idea of pedestrian use of the embankment sparked the plans for the Albert Embankment to be used as the bustling pedestrian city spot we see today.

 

Cultural significance

Sections of the Lambeth Bridge are painted red to signify the seats in the House of Lords and pylons were added on each end and topped with stone pinecones or pineapples (there is debate over what is represented)[3]. The Bridge Tour guide insisted they were pinecones, a representation of hospitality, but many believe they are pineapples as the Garden Museum is just over the bridge with reference Christopher Columbus whom is known for bringing pineapples to London and presenting them to royalty. To this day, the pineapples/ pinecones cause debate throughout London. Look at Figure 4 and see for yourself!

Figure 4: Pinecones or Pineapple?

Another argument caused by the bridge is less playful. The ferry operators remaining were very opposed to the construction of the bridge. This opposition was to the original Lambeth Bridge, not the one currently standing. The new Lambeth Bridge was well reciprocated because the old bridge was dilapidated and unusable. Luckily, the old bridge caused no injuries or deaths as it was closed before any extreme damage. The new bridge re-opened the pathway across the Thames to cars and pedestrians, helping disperse traffic. Crowds flooded the streets for King George V’s procession, officially opening the new Lambeth Bridge as seen in the video and art piece below [12]. The celebration was so grand it even inspired art, like that in Figure 5.

Figure 5: Grand Opening Inspired Art

Today, the bridge serves the same traffic purposes for cars, busses, bikes, and pedestrians. The increasing traffic, however, has ranked the Lambeth intersections among the top 75 most dangerous in London [11]. A woman on a bike was recently killed in an accident at one of the Lambeth roundabouts. The Lambeth Bridge is soon to be overhauled with safer bike lanes and newly designed intersections [11]. The 12 million pound project is a part of London’s goal to have 80% of people travelling in London to be on foot, bike, or public transit by making the roads safer to travellers [11]. This new project will hopefully make travelling across the bridge a better and safer experience.

The Lambeth Bridge has also been used in a few major films recorded in London. Examples include Harry Potter and the Prisoner of Azkaban, when the Knight bus rescues Harry from a bad holiday with the Dursleys it speeds over the bridge; in Fast and Furious 6, the bridge is used for a view of “Moscow”; and in The Foreigner with Jackie Chan, a bus exploded on the bridge [1]. The Jackie Chan film explosion of a bus caused panic throughout London.

 

Structural Art

            The Lambeth Bridge could hardly be considered structural art. The load path of the bridge is slightly visible through the side panels and from various angles, but is not clear. The Bridge is carried on granite-faced reinforced concrete piers and abutments [4]. The side panels and granite hide the elegance of the structure. Granite facing also adds unnecessary material and requires a stronger structure, taking away from the efficiency of the structure and requiring more expensive structural support. The tall obelisks located at either entrance are solely for aesthetics, adding more to cost. The attention to aesthetics also adds to cost in the metalwork and painting added to the structure. The exposed truss structures that make the light posts, if no small metal decals were attached, could be considered structural art. Overall, the structure does not satisfy any of the 3 E’s and therefore clearly cannot be considered structural art.

In regards to the three S’s of structural art, the Lambeth Bridge presents a bit better. As explained in the cultural significance section, the bridge is clearly very symbolic of its era. The symbolism of the bridge is mostly achieved by aesthetic decals and details added to the structure. The structure itself symbolizes the older designs of its time, so it is not so much structurally symbolic. Scientifically, the Lambeth Bridge does not have any breakthrough innovations. As a “basic” bridge for it’s time, there is no truly scientifically significant details about the bridge itself. Socially, however, the bridge is very influential. From the huge parade and celebration of its opening and connecting two sections of the city and therefore two communities to supporting green transportation, the Lambeth Bridge clearly satisfies the social aspect of structural art. Even though the Lambeth Bridge does better with the three S’s, it still cannot be considered structural art, as it does not satisfy all three S’s.

 

Structural Analysis

Lambeth Bridge is a five span, steel arch structure, carried by reinforced concrete foundations [4]. Steel caissons were used to make the piers [4]. The caissons were dug to the ground and the reinforced concrete foundations were put in place. The steel arches and supports were attached with pin connections, followed by the addition of the reinforced concrete deck and design features. The Lambeth Bridge was constructed very similarly to the Westminster Bridge, which was nearby, and many other bridges of its time.

I will be analyzing the repeating arches and their reactions at the pin connections with live and dead load. The total length of the bridge is 236.5m, with a 50.3m center span, surrounded by two 45.4m spans, and two shore spans of 38.1m [4]. Each span has 9 ribs supporting the reinforced concrete roadway above. See Figure 6.

 

Figure 6: Under the Bridge

The arches are all two-hinged with pin connections. There is a 60’ span on top of the bridge in reinforced concrete. I am assuming the concrete is 12” thick and using a live load of 640lb/ft, that of a truck [9]. By using this live load the bridge reactions will be for worst-case scenario. Reinforced concrete weighs about 150lb/ft^3

Clearance Per Arch in meters [8]

Lambeth 3.1 5.0 6.3 5.0 3.2

 

Load path

The example dead and live loads are observed as a constant force per linear foot. The load is carried from the deck, along the arches into the caissons to the ground. If these were repeating arches of the same height and width, the horizontal loads would cancel except for those on the ends. The horizontal loads do not perfectly cancel in the repeating arches, because they vary in size. This requires abutments to absorb the extra load on the ends. See the load path in Figure 7.

Figure 7: Load Path

Arch Calculations

Tributary Loads, because the beams spread evenly to the edges of the bridge:

Inner: 60’/8 sections

Outer: 60’/(8 sections x2) *because each outer only takes half a section

See the calculations in Figure 8.

Figure 8: Calculations

My calculations show a very simplified version of the calculations necessary to design the foundations and abutments of the bridge. With the reactions at each joint, the load needing support is known and can be designed for.

Design drawings depicted detailed plans for the Lambeth Bridge to the stakeholders and to the construction workers. Calculations were used to show how the load was distributed into the ground via the abutments and piers and caissons. A model for this bridge working was the similar Westminster Bridge adjacent to the Lambeth Bridge. Because of Westminster’s similar design and construction techniques, it acted as standing proof or a full-scale model of the Lambeth Bridge.

 

Personal Response

I never realized how truly necessary having so many bridges was to London. By walking to and across my bridge, I saw the traffic flowing across it and the surrounding bridges. The Lambeth Bridge is a relatively heavily trafficked bridge, and there were cars and pedestrians crossing, on a Bank Holiday at that. Additionally, on the map the bridge seems very distant from Westminster Castle and the Archbishop’s home, however, upon walking, I saw that the bridge arrives just at the Victoria Tower Gardens of Westminster and the Archbishop’s home.

 

References

[1] https://londonist.com/london/history/secrets-of-lambeth-bridge

[2] http://www.british-history.ac.uk/survey-london/vol23/pp118-121

[3] https://www.greatlondonlandmarks.com/place/lambeth-bridge/

[4] https://historicengland.org.uk/listing/the-list/list-entry/1393007

[5] https://www.lambeth.gov.uk/sites/default/files/pl-listed-buildings-beginning-with-l_0.pdf

[6] http://landmark.lambeth.gov.uk/display_page.asp?section=landmark&id=2955

[7] https://vauxhallhistory.org/lambeth-bridge/

[8] http://www.pla.co.uk/Safety/Thames-Bridges-Heights

[9] https://www.inti.gob.ar/cirsoc/pdf/puentes_hormigon/25-Lecture06-Design%20loads.pdf

[10] http://thames.me.uk/s00140.htm

[11] https://www.newcivilengineer.com/tech-excellence/lambeth-bridge-and-waterloo-to-get-37m-overhaul/10021157.article

[12] https://player.bfi.org.uk/free/film/watch-opening-of-the-new-lambeth-bridge-1932-online

[13] https://www.npg.org.uk/collections/search/portrait/mw271297/Opening-of-the-New-Lambeth-Bridge-King-George-V-Queen-Mary-and-others

 

 

Comments

  1. hmurray8 says

    I liked how you included the debate about the pinecone versus the pineapple. It made your post more interesting. I also appreciated how you included 3 different calculations for your arches. It showed the impact of the span on the forces. Great job!