There are criss-crossing rivers and beaches in the area where the West Ring Railway passes, and engineers and technicians will undoubtedly face technical problems such as seawater intrusion and underwater perfusion during the construction process.
The Zhubijiang double-track bridge and Taobaohe double-track bridge of Hainan West Ring Railway obliquely cross Zhubijiang and Taobaohe River, and the river sections they cross are close to the mouth of Beibu Gulf, which is affected by seawater intrusion to form tidal phenomena. During the construction of the two bridges, they were in an extremely serious corrosive environment under the simultaneous action of chloride and sulfate.
In view of this situation, engineers and technicians of China's high-speed rail construction have carried out research on the technical measures for upgrading the bridge structure under the high-temperature and high-humidity marine corrosion environment, and innovated a variety of anti-corrosion technical measures, which improved the durability of the bridge concrete structure and ensured the safe use of the bridge during its service life.
In order to ensure the smooth construction of underwater high-grade concrete for cast-in-place piles in harsh underwater corrosive environment, our country's high-speed rail construction engineers and technicians have strengthened their control from the aspects of concrete raw materials, concrete preparation and construction technology.
High temperature and humidity resistance
Hainan is located in the tropical marine area, and has been in a high temperature and high humidity environment for a long time, which puts forward higher requirements for the construction and maintenance of high-speed rail.
For example, in order to solve the durability problem of T-beam sidewalk in high temperature, high humidity and heavy salt fog environment in Hainan, railway builders adopted fiber reinforced composite (FRP) sidewalk brackets and pedals in Bowen Village double-track bridge (34 km and 382 m). Prior to this, several rounds of theoretical research, material performance test, sample trial production and sample bearing test were carried out, which accumulated rich experience for the popularization and application of railways in China.
The high temperature and humid air in Hainan are a great test for the maintenance of motor trains. The technicians of Sanya motor vehicle application formulated the implementation plan of "man, machine, material, method and environment", and refined and optimized the quality improvement, personnel training and environmental improvement of EMU. In particular, the insulation performance and moisture-proof function of the equipment are mainly rectified and accepted, and every part and bolt are spared to ensure the normal operation of the EMU.
Windproof, anticorrosion and salt spray prevention
In view of the special geographical environment of high temperature, high humidity, salt fog and frequent typhoons in Hainan, the power supply catenary has taken typhoon prevention measures. From the design structure, the integral wrist arm and rigid suspension structure are adopted, which are characterized by typhoon resistance and are suitable for coastal areas (the specified wind speed starts to decrease at 25m/s). The track fastener is treated by patented zinc-nickel infiltration technology, which reduces the maintenance cost and prolongs the service life.
Lightning protection and earthquake prevention
Thunderstorms often occur all over Hainan Island, especially in Haikou, which will be experienced for about one third of the year. Lightning protection technology has been strengthened throughout the West Ring Railway (Haikou section has the highest lightning protection). At the same time, an earthquake early warning system was set up along the line. The buildings and structures in Haikou area are designed according to the seismic intensity of 8 degrees, which is rare in Chinese mainland high-speed railway.