Height of 2 towers 27 floors, 2 basements. Gross floor area: 124,500m2
Type: High-rise mixed-use
Designed in 2008. Completed construction and put into use.
At the time of construction design, the project was large-scale, located in the central district of Dong Da. The project includes 2 high-rise towers: 27-storey apartment tower and 25-storey office tower on Tay Son street. 2 basements with an area of more than 1 hectare each. The 2 towers are connected by a 5-storey commercial center base. The project’s ground plan is designed to rotate along the street, creating a diverse space for the street. Below are 2 basements connecting the blocks together. The project is reasonably designed with gardens, flower beds, trees and walking paths.
Modern architectural plan with a typical square column grid of 8.4×8.4m. The design plan uses reinforced concrete structure as a load-bearing frame system along with the elevator core system to create great rigidity for each tower.
Office Block
The ground plan design uses flexible partitions. The requirement for office furniture is to be able to serve many different types of systems, according to user requirements. The basic size according to the column grid is 8.4m x 8.4m. The space serves 12 people to work while still ensuring a comfortable environment. The traffic and technical axis is arranged in the center of the tower. Maximizing the contact surfaces with nature of the office space, ensuring good ventilation.
Due to the flexibility of the open office space and partitions, the prestressed flat floor structure was chosen for the office tower. The use of beam-free floors also helps to create a large clear height, ensuring comfort for workers.
Analysis model of Structural framing Office tower
Analysis model and actual photo during Construction of PT slab Office tower
Apartment tower
Designed with nearly 300 apartments from the 6th to the 22nd floor with a total floor area of 36,700m2. The apartment floors of each tower are arranged with 8 elevators, including 2 large elevators for transporting goods and collecting garbage. The elevator core not only serves vertical traffic but also serves other technical and auxiliary functions. All apartments have at least one side in contact with nature.
The apartment structure uses traditional reinforced concrete beam floors. Secondary beams are arranged to support the walls separating the rooms. Depending on the bedroom interior, ensuring feng shui, avoid arranging beams above the bed, living room, etc.
Structural framing construction of 2 towers
Podium
The architects arranged a skylight in the middle of the commercial area. The purpose is to ensure air circulation and especially create a panoramic view, attracting customers to the commercial activities taking place on the floors. On the other hand, the skylight also creates a natural landscape inside the building.
Building a commercial center atrium
The structure used is still the traditional floor beam. The CGV cinema room needs to leave a row of columns empty to create a 17m wide space (equal to 2 grids of 8.4m columns). Therefore, the roof structure of this area uses beveled beams (haunch beams) with large spans and ensures economy.
17m large span haunches beam
Located above the commercial block is the technical floor. This is where technical requirements such as placing equipment, water tanks, as well as maintenance and service space for the technical area are served. In addition, there is a garden on the roof of the podium block to create a good climate environment for the building’s residents.
Deck of the central air-conditioning technical room of the building
Foundation
Mainly using bored piles with diameter D1200 to bear the load of the tower blocks. Pile depth from 51m to over 61m depending on the depth of the gravel layer that the pile tip leans on. The largest pile cap is at the foot of the stair cores of the building blocks.
Due to the complex geological fluctuations, the pile construction process requires the designer to handle and decide the depth to stop drilling the piles.
Basement construction
The basement excavation is large, extending close to the land boundary. The impact on the neighboring residential area is something that needs to be taken into account in the problem of supporting the excavation hole. A 600mm thick reinforced concrete diaphragm wall is selected. When excavating the ground, the basement area in the middle is dug out, the border area is supported by a reinforced concrete floor on the kingpost system before constructing the foundation and frame columns. Previously, the border area was supported by a soil slope (see more construction methods in the attached file). At the depth of the slope is sandy soil, prone to landslides. Along with water flowing into the foundation pit, increasing the displacement of the diaphragm wall when it rains, these are issues that design consultants must calculate and handle.
Basement construction excavation
Lotte mart retrofit
Due to business requirements, it is necessary to change the function to suit the new shopping center. Some commercial floor areas require a larger load than the original design. The problem of renovating the load-bearing structure is carried out on the constructed areas. The final renovation plan chosen is External prestressing.
Reinforcement of commercial floor beams with external prestressing
Participated with major design consulting firms for the project: VNCC and Finenco (architectural design). Large projects with diverse skills were carried out with a team of engineers and architects. Followed the project from the first conceptual sketches, supervised the author until the completion of construction. The completed project met the investor’s requirements in operating a multifunctional complex.
🎁Attached is the calculation explanation and construction method of the basement.
