How to Build a Bridge

By Mavis

Ten years ago, I was a quality examination person in a big factory (The Railway Department Baoji Bridge Manufacturer). I worked there for ten years when I was young.

In my memory, the huge bridge was built in our factory. This bridge is very famours and important in China. In 1996, we began to build it and finished in 2000. This bridge’s name is ‘Wuhu Yangtze Bridge’.

Wuhu Yangtze Bridge is a key traffic project ,‘The Ninth Five-Year Plan ’,of China . The bridge is a common type , iron dual-purpose steel longer cable –stay bridge ,railway ,grade ,double-line. The highway is a 4 lane, the driveway is 18 meters wide, or both sides all the pavement is 1.5 meters wide. The highway, in the upper strata is in the lower floor. The railway bridge is 10616 meters long. The highway bridge is 6078 meters long, among their step, the river bridge is2193.7meters long. It went into operation formally on March 22, 1997, was opened to traffic in September of 2000. The bridge rises 312 meters, like the combined cale-stay bridge of so large span, is the first in China, it is the first in Asia, there are very few in the world, come out at the top. The bridge highway is wired 23,23-km-long, its south bank is 7.35 kilometers, 15.88 kilometers of North banks. The projected grass investment of the bridge is 4.600 million Yuan. Many people call it ‘century huge bridge’. Meaning it was opened to traffic in September of A.D.2000. It was the beginning of the 21^st century and the end of the 20^th century. Second means it is the largest and most enormous bridge of the project amount in this century of China. Concrete consumption was 570,000 cubic meters, structural steel amount was 110,000 tons, it’s project amount exceeded ‘Wuhan Yangtze River Bridge ’with ‘Nanjing Yangtze River Bridge’. Total, last total length 10,500 meter bridge highway railways main. Third means Wuhu Yangtze Bridge is taller in scientific and technological content, collect the strong point of bridge science and technology in this century of China, its technological leading position will keep for more than 20 years. While it is the new starting point of bridge construction in China in the 21^st century. Wuhu Yangtze Bridge extensive with their new technology and first-class quality , become Chinese bridge continue Wuhan at the history. It is worthy of the century title of significant project of the bridge.

Now, I’ll tell you how to build a bridge. Some bridges construction only needs three and a half months, like a railway small and steel bridge. But this bridge can iterative used. Some new railway line begun, need temporary about 15 meters or 16 meter or 20 meter steel bridge, when this new railway begun used, this bridge will exchanged by the fixed rail. Most bridges, especially build on the river’s bridge need two or three or four years, even more we could finish.

Every new bridge’s build was so important and rigorous for the whole factory. You know building a bridge is a complicated and onerous and difficult work for us. Anyway all factory workers and all department must conquer the whole difficulties!

At first, the geological department surveyed an areas condition that needed a bridge built then they submitted reports to an academy of bridge building. Many architects design a plan to correspond to the area conditions and how long it will take to finished. When the plan are examined and approved, they are graded and passed by government, then the whole plans and blueprint are sent to the bridge building factory.

When the factory receives this plan, the technique department have many technicians, they analysed the whole bridge pictures, like us divided a picture for different and many small parts. At the same time, the manufacture department stipulates the product schedule. The product workshop must work according to the schedule, and the quality department will superintend the whole product quality.

The workshop has two parts: original procedure and half product procedure. Every part has 5 procedures.

ONE: The original procedures:

1^st: Original material examination. All primitive steel material must be qualified by a factory special laboratory chemical examination, Only then will it be use. Moreover the appearance quality, they geometry size needs to be qualified.

2^nd : Original material product (1)drawing line& enlarge picture: The worker will blow up blueprint which gives according to the technical department, the coiling or the large-scale steel plate delimits tallies the blow up shape. (2) Cutting. The flame shears, regarding the 6mm following steel plate , directly on alligator shears yummy treats . Surpasses 6mm the steel plate to need in the flame to cut from the gereratrix machine automation.

3^rd : Machine Product (1) milling: many milling machine tool use a revolving cutter to cut the surface, curve and groove into a metal work piece that is fixed on a work table and moves along with the cutter. (2) drilling: Many drilling machine metal cutting tool for drilling round holes in work pieces . A work piece is fixed at a working table and the drill cuts the hole while rotating. The bridge was made of many steel material, and these steel must be connect with many special holds.

4^th : First adjust: Every steel must adjust, the complanate, the aplomb, the straight angle, to favor the evil ways working procedure the assembly.

5^th :Assemble: The worker put the separate parts together into units or put units and parts into a half product.

After 1st—5^th completing the work piece is called the half-finished product. Enter the special half-finished product workhouse, for the evil ways working procedure separately.

TWO: The half product procedure:

1^st : electric welding: (1) The hand electric welding. (2) The machine electric welding. Some small and light and thin units need the workers put it together and electric weld it. Some large and heaven units must put it together by the machine and general term for.

2^nd : Exact adjust: After higher temperature, the whole material will change its shape or pattern. So the workers need exact adjust these again.

3^rd : Ultrasonic wave: Detect flaws in a metallic material by means of magnetism, like X-rays, Y-rays. Because all the product must be suffered more weight, it is very important for the electric quality. Only watch the welding lines and welding seams quality in our eyes are not able enough. We must used the special machine (Ultrasonic wave) to detected the inside quality for the welding lines or the welding seams. If have some inside flaw or electric shortcoming, when passing the long time, this welding lines will broke out.

4^th : Burnish: After the 2^nd and the 3^rd, units will enter the room which seals up completely By the high-pressure pump the hard sand blasting to the work piece surface , this work is similar to polishing. After hits the granulated substance smoothly the work piece, the surface neat.

5^th: Sprays paint: Spray paint on the metal product by means of a paint spray gun. First, the bottom fluid this kind of paint function is mainly the rust prevention, generally is the scarlet red, must spurt three. Second, the finish coat this kind of paint not can only guard against rust but also wants the water proofing against to expose to the sun rainproof, windproof, must spurt three. Each painting has thickness request, cannot be smaller than 60mm.

After the painting half–finished product will get the qualified steel seal, and will complete the mark. Has the special motorcade to pass through one week long to make a long and wearisome journey and arrival the bridge scene.

The factory already sent out the scene–the assembly personnel two months prepared ahead of time in the scene. All worker one year can go once home. No matter what the weather how about hotter or how about colder. The worker in the same storm stick it out, and tide over difficulties together , until they has insisted the bridge’s completion.

When we build a bridge, the most important thing is quality. The quality is a life for manufacture. Regarding our quality inspector, each bridge’s coming is a challenge. Every day we must be familiar with the blueprint, the research technical program, inspects each working produce the quality whether to fit the requirement. When we finished a bridge, we are very proud of ourselves. Look! This bridge is made by our factory! How wonderful! How splendid!

The most amazing thing about my job as an English teacher, is all the amazing people I get to meet. My students have so much knowledge about so many unusual and fascinating things. Do YOU know how to build a steel span bridge? Mavis does...

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