Zhengzhou, August 15 (Reporter Kan Li) The 89.5-meter-high "first pier" along the western extension of the Taihangshan Expressway was successfully topped out on the 14th, marking a breakthrough in the construction of the project. So, how was this thin-walled hollow "first tallest pier" built? Why a thin-walled, hollow design? The contractor analyzed this to the reporter of Chinanews.com.
The picture shows the site of the pier capping. Photo by Wu Yanfeng
The western extension project along the Taihangshan Expressway is one of the four expressways under construction in Jiyuan, the "13445 Project" of Henan Expressway, with a total length of 33.96 kilometers, using two-way four-lane standard construction, and a design speed of 100 kilometers per hour. The above-mentioned high pier is a thin-walled hollow pier with both limbs, which is the highest pier among the hollow thin-walled piers of Huling Special Bridge along the western extension of the Taihangshan Expressway, and the highest pier along the western extension of the Taihangshan Expressway, with a pier height of 89.5 meters.
So why use thin-walled hollow piers instead of solid ones? The relevant person in charge of the 10th Bureau of China Railway, the contractor of the project, told the reporter of China News Network that the thin-walled hollow pier is the best solution for the construction of high piers, and the effect is relatively good in earthquake resistance, which can not only save costs, save energy and environmental protection, but also reduce the weight of the pier body.
How was a thin-walled hollow pier nearly 90 meters high built? The above-mentioned person in charge introduced that the boring pile foundation needs to bury a casing to ensure the stable formation of concrete pouring, and this high pier adopts the latest "rotary drilling fast drive buried splicing casing" process on the casing, which not only shortens the burial time of the casing, but also improves the accuracy of burial. At the same time, the new material hydraulic climbing system is used to solve the complex problems such as vertical transportation, concrete pouring, and structural health care during the construction process.
The person in charge said that in terms of concrete pouring, according to the dense steel reinforcement of the pier and column, the large pouring drop, etc., the construction personnel optimized the concrete ratio from the third level to the second level, and at the same time used the string cylinder to reduce the pouring drop.
The picture shows the construction site of the piers in the Taihang Mountains. Photo by Zhang Jiancheng
He said that the construction of high piers belongs to special high-level operations, which is extremely difficult to construct and has extremely high safety risks, and key monitoring and management are required during the construction of the project. To this end, the project strengthens the safety management of high pier construction by establishing and improving safety management measures such as construction dangerous engineering accounts and strengthening safety organization and safeguard measures, so as to achieve comprehensive control of construction quality, safety and construction period.
The picture shows the construction site of the piers in the Taihang Mountains. Photo by Zhang Jiancheng
According to the contractor, the western extension project along the Taihangshan Expressway will be completed and opened to traffic in 2025. At that time, it will work with the Jiyuan-Xin'an Expressway and the Yellow Expressway to become an important part of the layout of the "three vertical and two horizontal" expressway network in Jiyuan City, providing important interconnection and transportation support for Jiyuan City to quickly build a national industry-city integration demonstration zone and strengthen economic exchanges and cooperation between Jin, Yu and Hebei provinces. (End)