Construction update: Symphony – Business Bay in Dubai
Gemini Property Developers and National Piling outline the progress of piling and foundation activities for the 29-storey Symphony tower in Dubai’s Business Bay
At the heart of Dubai’s business district, piling and shoring work is under way to build a 29-storey tower that will have a built-up area of 65,775m2, with 455 residential apartments, two basements, three podium levels for parking, and seven retail outlets on the ground floor.
The Symphony – Business Bay tower, being constructed by Dubai-based real-estate developer Gemini Property Developers, is the company’s second residential project in the city after Splendor at Mohammed Bin Rashid (MBR) City.
Apartments in the Symphony – Business Bay will comprise studios, one-, two-, and three-bedroom units, with areas ranging from 39.9m2 to 269.4m2. Amenities for residents will include smart-home technology, a gym, a swimming pool, a rooftop barbeque area, a jogging track, a children’s play area, and concierge services.
Everything fell into place for the Symphony – Business Bay project during the second half of 2017. The tower was conceptualised in June and design was completed in December.
After securing the shoring and piling permit in September, an enabling works contract worth $2.4m (AED9m) was awarded to specialist geotechnical and foundation engineering company National Piling in October.
The 120-day contract included foundation, dewatering, piling, and shoring activities, all of which were due for completion by May of this year.
Initially, Gemini Property Developers faced a delay in starting construction, due to accessibility issues that required evaluation and approval by Dubai’s Roads and Transport Authority. The entrance and exit of the site were restricted to one location from the main road, which intersects with a roadside cycling track.
Following the project’s ground-breaking ceremony in December last year, the developer handed over responsibility for the foundation work to National Piling.
“We chose National Piling due to our previous experience working with them,” said chief executive officer of Gemini Property Developers, Sailesh Jatania.
“Also, they submitted the most attractive tender price, and assured us that the work would be completed on time, which was a crucial requirement for us.”
The CEO of National Piling, Cheriyan P Alex, said: “Our team was on the ground immediately following the ground-breaking ceremony in December, in order to ensure that the project was delivered within the construction time frame.”
Laying out the scope of the project, the deliverables, and the timelines, Alex explained: “The shoring system comprises a 700mm-diameter secant pile wall with one level of tie-back anchors for an average excavation level of 8.55m below the existing ground level.”
He added that the duration of the shoring works was 50 days. “The average excavation quantity is approximately 42,000m3 up to 8.55m below the existing ground level. The existing water table is at -6m below ground level.
“The dewatering works start from [-4m below ground level] to keep the water table 1m below the final formation level,” he continued. “We started our foundation piling activity from -4m below ground level to avoid dewatering during piling installation.”
Piling and testing was due to last 66 days, he added. “The total number of piles is 185, with diameters of 900mm, 120mm, and 1,500mm.”
By mid-April, National Piling had completed the secant pile wall works for three sides and installed the tie-back anchor.
“Shoring has been completed on three sides, and excavation has started, reaching depths of 9–14m,” Jatania said at that time.
“We encountered loose soil on the fourth side, which required a pile redesign and separate approval.”
Subsequently, foundation piles designed by National Piling were to be laid to support the building. According to Jatania, the excavation work was expected to be completed by the end of April.
National Piling’s Alex added that “the secant pile wall works for the forth side and the excavation to the piling platform [would] commence soon”.
“The installation of foundation piles will start after excavation to -4m below ground level. We will do the static and dynamic tests on the working piles from the same level,” he said, adding that “the final excavation and cutting of pile heads” would start after the dewatering works had commenced.
“After the excavation to final formation level and pile head cutting, the pile integrity test and sonic test will be carried out on the piles,” he said.
National Piling used four drilling units and three 55-tonne crawler cranes for the secant pile wall installation. Alex indicated that the same number of rigs and cranes would be used for the installation of the foundation piles.
As the enabling works neared completion, Gemini Property Developers had yet to appoint a main contractor for the project.
Jatania said that a tender had been issued, however, and the company planned to announce the main contractor by the end of April, with the construction to be awarded in a single phase.
“We estimate that 24–30 months will be required for completion,” he said.
Managing director of Gemini Property Developers, Sudhakar R Rao, commented: “The awarding of the piling and shoring contract happened within weeks of getting the necessary permissions from relevant government authorities.”
He added that the firm always aimed to start construction work “well before the commercial launch of the project”, due to its policy of “build first, then sell”.
“The construction of the Symphony – Business Bay reinforces our faith in the Dubai market,” added Rao, explaining that the project began just as the firm was preparing to deliver its first project, Splendor at MBR City, which had been “well received by the investors and end users”.