Shangri-La Hotel – A High-Rise Building on Coral Rock

The Shangri-La Hotel is just a hundred metres from the Red Sea, located near what used to be a coral reef. The coral stone has large irregularly shaped voids and channels mostly filled with coral sediment. Constructing the high-rise building posed unique challenges that our experts overcame in planning and support services while laying the foundations.

The high-rise rests on a 3 m reinforced concrete slab built on 125 foundation piles at a depth of 50 m. The excavation pit to accommodate the basement floors enclosed single-layer tied-back anchored diaphragm wall measuring 400 m in length and 20 m in depth; a deep injection well at a planned thickness of 4 m was used to reduce groundwater intrusion, and thirty deep wells were installed to drain the construction pit and remaining water. Around 1,800 m³/h of groundwater was extracted and drained to the Red Sea via two underground DN800 pipes on lowering the water table to the required depth.

With the aid of the Finite Element Method, we inves­ti­gated the support and deformation behavior of the high-rise building. The 3D geot­ech­ni­cal model, in addition to the foundation and foundation structure, also determines the structural elements of the ground floor that are decisive for the load transfer. The calibration of the model and the derivation of material parameters for the higher-value substances used were based on pile loadings. In a sensitivity analysis, we examined the influence of cavities in the coral rock and determined the feather stiffness of the foundations for the structural design.

We were commis­sioned with design review, site management and local construc­tion management and quality assurance in the excavation and foundation work. Our local team consisted of a resident engineer, supervisors, specialist engineers for geot­ech­ni­cal and foundation engineering, geologists, concrete engineers, secretaries and surveyors.