Project Overview
Project P-2024-117 involved the complete structural engineering of a landmark entertainment complex in Dammam, Eastern Province, Saudi Arabia. The centrepiece is a steel observation and entertainment tower exceeding 150 ft (approximately 46 metres) in height, designed to function as both a structural and architectural statement for the entertainment destination it anchors.
The commission covered the full structural scope: primary tower steel frame design, secondary structure for platform levels and viewing decks, connection design for all joints, foundation design for the tower base and complex footprint, and a comprehensive design report prepared for Saudi authority review. The project exemplifies the multi-standard approach that characterises our international practice — Saudi Building Code requirements apply locally, while AISC-360 provides the steel design methodology and IBC provides the load combination framework.
Structural System
The tower structure is a braced steel frame — four primary W-shape columns connected by horizontal ring beams at each platform level, with diagonal bracing in each face panel providing lateral stiffness against wind and seismic forces. The braced frame configuration was selected over a moment frame for this structure because it concentrates the lateral resistance in clearly defined brace panels, making connection design and force transfer transparent, and because the braced frame achieves the required stiffness with lighter member sizes than an equivalent moment frame at this height.
The primary columns are continuous over multiple floors, with splices at erection crane reach intervals. Column sizes were governed by combined axial compression from gravity loads and biaxial bending from wind loading, analysed under the governing ASCE-7 wind load combinations referenced by SBC 301. The primary analysis was performed in STAAD.Pro with a full 3D model including all bracing, platforms, and accessway loads.
Saudi Wind and Seismic Loads
Saudi Building Code SBC 301 governs structural loads for the Kingdom of Saudi Arabia. For wind loading, SBC 301 references ASCE-7 methodology with Saudi-specific basic wind speed maps and terrain exposure categories. Dammam, on the Arabian Gulf coast, is classified as Exposure D — the most severe open-water exposure category — which applies the highest wind pressure amplification factors. This makes wind the governing lateral force for the majority of the tower height, with wind pressures calculated using the analytical procedure of ASCE-7 Chapter 27 (buildings) and Chapter 29 (other structures).
SBC 303 addresses seismic design for Saudi Arabia. The Eastern Province has a defined seismic hazard, though lower than the Red Sea coastal region. Seismic design was performed using the equivalent lateral force procedure, with site class determination based on geotechnical data from the project's soil investigation report, and spectral acceleration values from the SBC 303 seismic maps for Dammam.
AISC-360 Member Design
All structural steel members were designed per AISC 360-22, the Specification for Structural Steel Buildings. The tower primary members were checked for all applicable limit states: axial compression (flexural buckling, torsional buckling), flexure (yielding, lateral torsional buckling), shear, and combined loading per Chapter H interaction equations. The governing member for most column sections was combined compression and biaxial bending under the worst-case wind loading direction, with the AISC Chapter H bilinear interaction equation applied for all sections.
Platform beam members were checked for flexure and serviceability (deflection under live load). The live load on entertainment viewing platforms — 100 psf per IBC Table 1607.1 for assembly use — governed the beam design over wind and gravity combined loading on these elements.
Connection Design
Connection design for the Dammam tower was particularly demanding because the entertainment use generates dynamic loading from crowd movement and vibrating equipment. Connections were designed for static AISC demand forces with dynamic amplification factors applied to the live load components. All moment connections at column-to-beam interfaces were fully restrained (FR) connections designed per AISC 360-22 Chapter J, with column stiffener plates provided at all beam flange load-introduction points to satisfy AISC 360 Section J10 concentrated force checks.
Base plate and anchor rod design followed AISC Design Guide 1 procedures. The anchor rods were designed for the full tension uplift generated by overturning wind moments at the tower base, with embedment depths in the concrete foundation verified for both the steel rod tensile capacity and the concrete breakout cone failure mode per ACI 318-19 Appendix D provisions.
Foundation Design in Saudi Soil Conditions
The Eastern Province of Saudi Arabia presents challenging soil conditions for deep foundations. The upper soil profile in the Dammam area commonly includes sabkha deposits — salt-laden, highly compressible soils with variable cementation that lose strength rapidly upon wetting. Below the sabkha layer, denser sand and limestone formations provide adequate bearing capacity for spread footing foundations provided the foundation depth exceeds the sabkha stratum.
The tower foundation was designed as a reinforced concrete mat foundation placed below the sabkha layer on competent dense sand. The mat dimensions were sized to limit net bearing pressure to the allowable bearing capacity stated in the geotechnical investigation report, with overturning stability checks under the governing wind moment confirming adequate factor of safety against rotation. Concrete mix design specified for the saline environment included sulfate-resistant cement and maximum water-cement ratio per ACI 318-19 Table 19.3.3.1 for Class 3 exposure (severe sulfate).
Design Documentation
The complete design documentation for this project comprised over 200 pages of calculations and 45 drawing sheets, organised for submission to the relevant Saudi municipal authority and for the client's construction management team. The calculation package included a structural basis of design, full load calculation derivations, STAAD.Pro model documentation, member design tables, connection design sheets, and foundation design with geotechnical parameter derivation — all formatted to the standards expected by Saudi Authority review engineers.
All Saudi projects are designed to SBC with explicit cross-referencing to AISC and IBC. Saudi reviewing authorities expect to see both local code compliance and international best-practice alignment — our documentation provides both.