Construction method of suspension bridge

If the tower is to be built on the water, a caisson must be used to squeeze out the soft ground in the place where the tower is to stand, to build a fixed foundation. If the underlying rock layer is very deep and cannot be reached with a caisson, then use deep drilling to reach the rock layer or build a very large artificial concrete foundation. This foundation has to extend out of the water. If the tower is to be built on land, its foundation must be very deep, and concrete, boulders and steel structures are used to build piers on the foundation. Some bridge piers are part of the bridge deck, in this case the height of the bridge piers must be at least the height of the bridge deck.

On the top of the tower is a smooth structure called a saddle. The saddle may have to be fixed after the bridge is completed. The anchor is fixed in the rock, and a temporary rope or string is towed along the path of the future suspension cable. The other strand is suspended above the first strand, and a pulley can run on this strand. This trolley can run from the anchor at one end to the anchor at the other end. Each suspension cable needs one such pulley. A section of a high-strength steel wire with a diameter of generally less than 1 cm is fixed in an anchor, and the other end is fixed to the pulley and pulled to the anchor at the other end in this way. It is fixed on this anchorage, and then the pulley returns to the anchorage it started to pull the next strand of high-strength steel wire or pull the next strand of high-strength steel wire from the direction where it is.

After the steel wire is towed, anti-rust treatment is required, so that multiple strands of high-strength steel wire are towed to connect the anchorages at both ends. Generally, the cross-section of these steel wires is hexagonal. They are temporarily tied together. After all the steel wires are pulled, they are squeezed together by a high-pressure hydraulic mechanism and other steel wires, so that the cross-section of the suspension cable formed is circular. .

Cable clamps should be added at equidistant positions on the suspension cable, and the suspension cable with a calculated length in advance is mounted on the cable clamp. The other end of these suspension cables will be fixed on the bridge deck in the future, using a special crane, and the bridge deck will be hung on the suspension cables one by one. The crane can be hung on the suspension cable itself or on a special temporary cable. The bridge deck can be hoisted from a ship under the bridge or transported from both ends of the bridge to where they should be placed. When all the bridge decks are hung up, the bridge deck can reach the planned curve by adjusting the suspension cables. Generally, the bridge deck on the water surface is arched to facilitate the passage of ships under the bridge. The deck of a suspension bridge on land is generally flat. After the bridge deck is completed, other details can be carried out, such as drainage and waterproofing system, expansion joints, lighting, railings, painting, paving and so on.