Project Overview

The Landscape Tower is located in the Liangjiang Collaborative Innovation Zone of Chongqing. There are Mingyue Lake and Mingyue Mountain in the park, and a large number of buildings have been arranged around Mingyue Lake, attracting many entrepreneurs to stay there. The demand for providing park users with a panoramic view of the mountains and rivers and a place to relax and unwind has emerged. We were entrusted by the owner to choose a site to build the tower.

Organisation

gad Design Group Ltd

Team

Wu Yan, Guo Tongjiang, Huang Jia, Wu Zhenhui, Liu Zheng (architecture); Yang Guanglei, He Song, Gao Hongwei (structure); He Changyan, Feng Yuanmeng (Landscape)

Project Brief

The shaping of sensory imagination requires rational implementation of mechanical logic, and only a sufficiently slender supporting structure can achieve architectural intent. The integrated design of space structure has become a key element in project implementation.

Considering the form, stair path, structural force transfer efficiency, etc., the structural design uses "frame column+swing column+stair slant support" to jointly build the support system of the project:
Six frame columns transmit vertical forces and bear bending moments to participate in lateral resistance;
Six swinging columns assist the frame columns in transmitting vertical forces but do not participate in lateral resistance to minimize diameter;
The inclined beam system of the staircase surrounds and connects six frame columns in series, forming a lateral force-resisting system similar to a supporting frame to enhance the overall structural integrity.

Project Innovation/Need

The shaping of sensory imagination requires rational implementation of mechanical logic, and only a sufficiently slender supporting structure can achieve architectural intent. The integrated design of space structure has become a key element in project implementation.

Considering the form, stair path, structural force transfer efficiency, etc., the structural design uses "frame column+swing column+stair slant support" to jointly build the support system of the project:
Six frame columns transmit vertical forces and bear bending moments to participate in lateral resistance;
Six swinging columns assist the frame columns in transmitting vertical forces but do not participate in lateral resistance to minimize diameter;
The inclined beam system of the staircase surrounds and connects six frame columns in series, forming a lateral force-resisting system similar to a supporting frame to enhance the overall structural integrity.

Design Challenge

If the upper limit of the slenderness ratio of conventional steel columns is calculated in reverse, the diameter of the steel columns in the landscape tower should be at least 300mm, but this cannot achieve the design requirements of a "lightweight and slim" floating feeling. Therefore, we adopt a performance-based design method of "high bearing capacity low ductility", breaking through the conventional aspect ratio limitation by increasing the bearing capacity surplus of steel columns, and ultimately achieving a frame column diameter of 245mm, aspect ratio of 150, and a sway column diameter of 152mm, aspect ratio of 200.

The reduction in cross-sectional diameter weakens the lateral stiffness of the structure, and even if the bearing capacity meets the requirements, there will still be perceptible horizontal shaking during wind and large-scale crowd activities. In order to improve the comfort level of the experience, considering that the structural stiffness and weight are greatly affected by construction conditions, the project conducted vibration measurements after the main structure was basically completed, and further analyzed the perceived comfort level through computer calculation. Finally, by adding four 500kg Tuned Mass Dampers (TMDs) arranged along two main axes, the vibration reduction efficiency exceeded 50%.

Sustainability

As a long-term outdoor construction, when selecting materials for the landscape tower, we fully consider the structural load, operating costs, low-carbon, and environmental protection. We have decided to use "recyclable steel" to construct most of the structures, and the structures are all exposed without excessive use of other materials for decoration or shading, making the structure itself present a light and orderly beauty. This can reduce the use of materials, save consumables, and achieve low-carbon and economic sustainability.