Constructed with great care by Shanghai Construction Group over a period of 6 years，recently, in the core area of Ningbo Eastern New Town, the 409-meter-tall Ningbo Center, the "Tallest Building in Zhejiang", constructed by Shanghai Construction No.1 (Group) Co., Ltd., was officially delivered and put into use.

Ningbo Center is jointly invested and developed by Shanghai Construction Group, Shanshan Corporation, and Greentown China Holdings Limited. With a total construction area of approximately 252,800 m3, it has 80 floors above ground and 3 floors underground. It integrates international Class-A office buildings and super five-star hotels. Floors 1 to 60 are international Class-A office buildings, and floors 61 to 80 are the world's top luxury hotel, the Ritz-Carlton.

Since December 29, 2018, when the first 110 m super-deep rock-socketed pile of Ningbo Center was driven, over 2,293 days, the project team of the First Construction Group, in view of the engineering characteristics such as super-deep foundation pits, ultra-high curved surfaces, complex setbacks, and limited site space, has continuously refreshed the construction records of skyscraper landmarks with their craftsmanship and wisdom.

Deep Dive Downward

During the "deep dive downward" process of the project, the project team overcame three major challenges: the construction of a group of 259 rock-socketed piles with a diameter of 1.1 m and an average hole depth of 110 m in a narrow site, the construction of a near-railway deep foundation pit with a maximum excavation depth of 26 meters, and the construction of a 4.2-meter-thick foundation slab weighing 5,200 t.

By developing the construction technology for super-deep rock-socketed bored piles with a large slenderness ratio and high bearing capacity at the 100-meter level, upgrading the micro-deformation control technology for deep foundation pits, and optimizing the design of dense steel bar joints in ultra-thick foundations, the project team finally ensured the one-time continuous pouring of 22,000 m3 of high-performance concrete, setting a new local record for the one-time pouring volume of high-performance concrete for ultra-thick foundation slabs.

One-time pouring of high-performance concrete for ultra-thick foundation slabs

Growth Upward

Facing the situation of limited site space and the complex working conditions of the setback and deformation of the core tube, the project team developed an integrated tower crane steel column cylinder frame alternating support type integral hydraulic climbing steel platform formwork equipment, which is suitable for the construction of complex-shaped core tubes. It integrates large-scale construction facilities such as tower cranes, construction elevators, evacuation platforms, and concrete placing systems.

Integral steel platform for integrated tower

During the construction of the 370-meter-high main structure core tube, this equipment withstood the tests of four strong typhoons, and the "growth upward" speed could reach an average of 5-6 days per floor.

Ningbo Center climbs to 300 meters

In response to the construction challenges of C60 concrete and ultra-high pumping at 395.53 m, the project team developed the control requirements for key parameters of high-performance ultra-high pumping concrete, refreshing the concrete pumping strength and height records in the Ningbo area.

High-performance concrete ultra-high pumping

Moving Forward with Innovation

During the construction of this super project, the project team of Shanghai Construction No.1 (Group) Co., Ltd. innovatively adopted the operation and maintenance management technology for limited sites in super high-rise construction, achieving efficient underground construction in a limited site within 10,000 m3 and the efficient turnover and utilization of a 30-meter effective construction zone around the tower. They comprehensively applied BIM technology, introduced 3D virtual construction into the detailed node structures to ensure management accuracy and project quality. They also developed the comprehensive construction technology for complex spatial steel structure tower crowns, enabling efficient multi-professional flow construction in a limited space.

The Comprehensive Construction Technology for Complex Spatial Steel Structure Tower Crowns

During the construction period, the project team undertook 3 national-level subject demonstration tasks, obtained 11 authorized invention patents, 10 utility model patents, and 2 provincial and ministerial-level construction methods. The key technology achievements in the construction of ultra-high structures won 1 first prize and 2 second prizes of provincial and ministerial-level scientific and technological progress awards.

In addition, during the construction process, the project reduced carbon emissions by approximately 23,000 tons, and successfully passed the review of Zhejiang Province's Green Construction Demonstration Project.