IELTS Reading Intensive Lesson - London Swaying Footbridge - Trí Đức English TRÍ ĐỨC ENGLISH IELTS Reading Intensive — Passage Analysis & Practice I. READING PASSAGE: London Swaying Footbridge [Paragraph A] In September 1996 a competition was organized by the Financial Times in association with the London Borough of Southwark to design a new footbridge across the Thames, which at that time would be London’s only pedestrian bridge and the first new crossing on this part of the Thames. The news quickly spread nationwide and worldwide through TV stations and radio network. The competition attracted over 200 entries. In the end, architect Sir Norman Foster, sculptor Sir Anthony Caro as well as Arup (an engineer team) took the top prize. The Millennium Bridge represents a creative collaboration between architecture, art and engineering. As a key element in London’s pedestrian infrastructure, this bridge has created new routes for Londoners and encouraged new life on the embankment alongside St Paul’s. [Paragraph B] On 10th June 2000, the bridge was opened to the public. It is estimated that 100,000 people crossed it that day, and there were up to 2,000 people on it at any one time. Initially the bridge remained stationary, but it gradually began to sway. Although a few visitors raised the concern when they reached the other end of the bridge, the organizer was not aware of how serious the safety problem was until it began to wobble more noticeably when a large group of people were crossing. The wobble became so marked that people needed to stop walking to regain their balance, and even grab the handrails for support. Quickly, quite a lot of people realized that the bridge was not safe for walking. The decision to immediately limit the number of people crossing was taken, but even so the deck movement was sufficient to make people uncomfortable and to raise concern for public safety so that on 12th June the bridge was closed until the problem could be solved. [Paragraph C] Embarrassed, the engineers searched out a video recording which showed the center span oscillating about 3 inches side to side each second. The engineers first thought that winds might be exerting excessive force on the many large flags and banners bedecking the bridge for its gala premiere. However, they discovered that the pedestrians themselves had a significant impact. Normal human activities like jumping, running, swaying and even walking can create horizontal forces which cause excessive dynamic vibration in a lateral direction on the bridge. As they felt the bridge moving, the pedestrians would naturally have adjusted their walking style to the same rhythm as the bridge. These altered footsteps would have made the motion worse—something like when four people in a boat all stand up together. As more pedestrians copied the movements of the bridge, the dramatic swaying increased, as seen in the video. [Paragraph D] The engineers realized that in order to reduce the movements of t...