Designed and built in 2014, started construction in 2015. The project was completed and put into operation in 2017.
This is a twin tower project consisting of 2 32-storey apartment buildings, with a total floor area of over 150,000m2. The location is right on the spacious new Tan Mai street, creating great value for apartment real estate. The architectural design language is modern and simple. The facade is stepped in height, ensuring the construction density according to the planning, avoiding the monotonous feeling like a matchbox, and natural ventilation for all apartments. The design consultant focuses on the main function of housing, the key real estate business product. The apartments are designed with open space for the maximum number of rooms. This design also creates a clear view from every corner, bringing the most comfortable living experience to residents. Therefore, the investor added a swimming pool utility on the roof of the podium, which is a 6-storey commercial center. Extremely spacious parking space under 2 basements, actually considered 3 floors with 2-3 floors automatic parking system in basement 1.
Based on the requirement to maximize the functionality of the apartment, structural design engineers have proposed many options to consider from the conceptual design stage, including the following items:
Structural column option
Typical apartment floor load-bearing structure design ideas
The idea comes from the apartment floor plan to advise on column grid design. Flat columns are always chosen to optimize the clear area, which is the business area that turns into money for the investor, according to the regulations of the new construction law. If using a square column structure, it will not only take up space but also lose the interior aesthetics.
The most beautiful is the column hidden in the wall, the design engineers have chosen a column thickness of 250mm. The column should be constructed with plywood formwork, so that the finished concrete surface is flat and beautiful without the need for plastering. The column thickness is therefore equal to the wall thickness including plastering. The column length is calculated to bear the load, the remaining length is the brick wall according to the partition wall.
Floor framing plan
As mentioned, the floor structure accounts for a large proportion of the construction cost. Therefore, design engineers must spend a lot of time paying attention and convincing for their choice of this structure.
Weighing with the Prestressed floor, with the column grid with a small span of the apartment block, the beam floor structure is chosen. The beam width is designed equal to the column width, for convenience in construction and structure of connection with the frame column. Therefore, the beam is also hidden in the partition wall, the beam height can be freely selected according to the load-bearing requirements. Another reason for using beam floors for housing functions is that there are many positions for the toilet floor, loggia, and technical openings. If using prestressed force, the floor structure will be complicated, and it will not be flexible if you want to drill and chisel according to the interior changes in the apartments later.
The design of the beam structure is hidden in the partition wall, there is no beam in the middle of the room, so the clear height to the concrete ceiling of the rooms is up to 3m. This is a huge benefit in terms of convenience, luxury, especially for the living room space.
Apartment structural design ideas – Visualization of the living room load-bearing frame
Apartment Structural Design Ideas – Visualization of Secondary Beams on the Corridor
Foundation Plan
With a large number of floors, only bored pile foundations are suitable structures. Due to the large number of piles, the design engineer needs to optimize the pile structure. Choose large piles for the tower block and smaller diameter for the Podium.
Structural design – Comparative pile options
– Option 1: D1500 and D1000 💶164 billion
– Option 2: D1200 and D1000 💶170 billion
The individual pile cost estimate shows that option 1, D1500 piles, has a smaller number of piles (hence the pile drilling progress) and cost. If we consider that the foundation cost must be larger for more D1200 piles, the reason for choosing option D1500 is even more convincing.
Choosing basement floor structure option 2: should we make a flat floor for easy pouring or make a floor with beams (foundation beams)? After comparing the economic calculations, the structural engineer was forced to choose the floor option with foundation beams, specifically as follows:
Estimated cost of constructing basement 2 floor beams:
– Option 1: 600mm thick beam-free floor 💶50 billion
– Option 2: 350mm thick floor with foundation beams 💶42 billion
Basement construction method
The basement covers the entire land area of more than 1 hectare. The design engineer expected the basement construction method to be quite similar to the Mipec Tower project: digging a large hole combined with Semi-topdown to support the perimeter of the basement, using Kingpost steel profiles buried in piles as temporary support columns.
The deepest excavation location is the wastewater treatment plant area, underground under basement 2 (depth equivalent to 4 basements). The problem of supporting the excavation hole for this most dangerous area, which needs to be done on the Plaxis model, is the problem of 2 layers of earth retaining walls.
The foundation pits under the elevator core are also deep, requiring additional layers of sheet piles when digging similarly.
Below is a summary of the project’s basement construction steps:
(if you don’t like to listen to the sound, turn on Vietsub, CC button)
🎁Attached is the construction design explanation, calculation of excavation pit and basement construction method.
