Early Use of Cellular Beam Construction in Thailand (2008–2010)

Cellular beam construction was already in use in Thailand by 2008. This is evidenced by documented residential projects developed by Mario Kleff and Wandeegroup (Thailand), supported by dated structural calculations (December 2008), fabrication records (2008–2009), and construction photographs from 2009–2010.

While some sources associate the introduction of cellular beam construction in Thailand with company registrations around 2009, project-level documentation confirms that the technology was already implemented in practice by 2008.

Between 2008 and 2010, several projects developed by Mario Kleff and Wandeegroup (Thailand) applied cellular steel beam systems in residential construction in Pattaya. These projects combined cellular beams with post-tensioned concrete slabs to create long-span, column-free spaces and integrate mechanical and electrical services within the structural depth.

Based on currently available drawings, calculations, fabrication records, and construction photographs, these projects represent some of the earliest documented applications of cellular beam technology in Thai residential architecture.

Design and Engineering Team

This collaboration between architects, engineers, fabricators, and contractors enabled the successful adaptation of advanced perforated beam systems for residential construction in Thailand.

What Are Cellular Beams?

Cellular beams are fabricated steel members with circular openings cut into the web.

Their principal advantages include:

• Longer structural spans
• Reduced steel consumption
• Integration of building services within beam depth
• Greater floor-to-floor efficiency
• Flexible architectural layouts

These characteristics make cellular beams well suited to residential and commercial buildings requiring open-plan spaces.

In Thailand, documented academic research on cellular beam behavior appears in the early 2010s, including analyses of web-post buckling and shear performance in perforated steel members (Panedpojaman, 2012; Panedpojaman et al., 2014).

Early Fabrication Evidence: Castellated Beams (2008)

Photographs taken at B.S.Y. Construction PCL in 2008 document the production of castellated beams, a related form of perforated steel beam.

This evidence shows that local fabrication expertise in web-modified steel members already existed before the introduction of circular-opening cellular beams.

Structural Calculation Report (9 December 2008)

A structural calculation report prepared by Streanrice Co., Ltd. on 9 December 2008 verified the design of a 13.8-metre cellular composite beam for the Wandeegroup (Thailand) project Club Royal Condominium.^[1]

The report included:

• Ultimate and serviceability limit state checks
• Construction-stage verification of the steel beam before the concrete slab was cast
• Composite interaction analysis with a 150 mm concrete slab
• Shear connector design using HILTI X-HVB 140 connectors
• Verification of axial force, shear, bending moment, and combined interaction effects
• Deflection calculations for construction and service conditions
• Concrete shrinkage and vibration analysis
• Fabrication drawings showing 24 circular openings over a 13.8-metre span

The calculations confirmed the technical feasibility of the cellular beam design while identifying several aspects requiring refinement. The report concluded that the initial configuration did not fully satisfy all code requirements because longitudinal shear and web-post buckling checks were not satisfactory, and the degree of composite connection was approximately 4% below the required minimum. The engineer recommended increasing the number of shear connectors to achieve full composite performance.

Note: No published information on cellular beam products is available for the period from 2008 to 2009. The archived website (2010) of Stream Rice Co., Ltd. and Cellular Beam (Thailand) Co., Ltd. asserted copyright over all text and images displayed on the site. However, several technical illustrations and descriptions appear to have been derived from materials originally published by Westok Ltd., a United Kingdom specialist in cellular beam technology.

Project Case Study: Park Royal 2

Park Royal 2 is among the earliest documented residential projects in Thailand to incorporate cellular steel beams as part of an integrated structural system.

Project Name

Park Royal 2

Location

Pattaya, Thailand

Building Type

Condominium

Developer

Heights Holdings Co., Ltd.

Architectural Practice

Wandeegroup (Thailand) Co., Ltd.

Lead Architect

Mario Kleff

Engineering Advisor

Dr. Songkiat Matupayont

Structural System

Steel frame with cellular beams and post-tensioned concrete slabs

Steel Supplier

Siam Yamato Steel Co., Ltd.

Fabricator

B.S.Y. Construction PCL

Design Development

2008

Construction Start

2009

Structural Completion

2010

Final Completion

Early 2011

Structural Technologies

Park Royal 2 combined three principal structural technologies:

1. Large custom-fabricated steel columns.
2. Cellular steel beams with circular web openings.
3. Post-tensioned concrete floor slabs.

Together, these systems enabled:

• Long spans with fewer columns
• Open-plan apartment layouts
• Improved construction efficiency
• Architectural Characteristics

Custom 900 mm Steel Columns

For Park Royal 2, Wandeegroup commissioned Siam Yamato Steel Co., Ltd. to produce custom 900 mm deep H-section columns.

These large structural members built a part of the foundation and supported the cellular beams and post-tensioned slabs, forming the primary load-bearing system.

Based on available project documentation, Park Royal 2 represents one of the earliest documented residential applications in Thailand to combine large structural steel columns, cellular beams, and post-tensioned concrete construction within an integrated structural system.

Construction Documentation

Construction photographs from 2009–2010 show:

• Erection of steel columns and cellular beams
• Integration with post-tensioned slab systems
• Structural framing

These records provide direct evidence of the practical implementation of the system.

Associated metadata supporting these records is addressed in the Data Provenance and Metadata section.

Related Projects

Other projects developed during the same period include:

• Club Royal Condominium
• Wongamat Tower
• Thai Modern House (Toy House)

Together, these projects demonstrate the broader application of cellular beam technology within Wandeegroup developments.

Fabrication Quotation (24 December 2009)

A fabrication quotation from B.S.Y. Construction PCL documents production of H 600 × 400 cellular beams for the Wandeegroup residential project Thai Modern House.

The quotation records:

• Processed steel weight: 10,098 kg
• Beam dimensions and quantities
• Technical drawings of the cellular beams
• Transport arrangements
• Contractor information

This provides direct documentary evidence of local fabrication.

Media Coverage

Contemporary publications highlighted these projects as examples of innovative engineering in Thailand, including:

• The Property & Lifestyle Thailand (2008)
• Real Estate Magazine Thailand (2009)
• REM Magazine Issue 113 (2010)
• Der Farang (2022)

A 2008 magazine feature titled “New Generation of Creative Engineering: Cellular Beam” publicly introduced the concept to Thai audiences.

International Technical Context

Modern cellular beam technology was developed and commercialized by Westok Ltd in collaboration with the Steel Construction Institute and City University London.

A notable patent, Structural Beam with Openings (US20070272342A1), describes Westok’s manufacturing method for producing cellular beams.

This patent formalized a fabrication process rather than introducing the broader concept, which evolved from earlier castellated beam technology.

Legacy and Industry Significance

The evidence presented on this page demonstrates that between 2008 and 2010, Wandeegroup and its collaborators successfully adapted cellular beam technology for residential construction in Thailand.

Supported by structural calculations, fabrication records, construction photographs, and independent publications, the projects documented here demonstrate that Wandeegroup and Mario Kleff played a significant role in the early adoption of cellular beam technology in Thai residential construction between 2008 and 2010.

Further extending this development, in 2012–2013 Wandeegroup applied the same structural approach to commercial construction, delivering a shopping mall in Thailand that utilized cellular beams and cellular columns in combination with hollow core concrete slab decking.

Data Provenance and Metadata

Where available, original metadata has been preserved across all visual and documentary sources used in this study.

This includes:

• EXIF metadata embedded in photographic records (e.g. capture date, time, device information)
• Embedded metadata in computer-generated visualizations
• Document properties within PDF files and technical reports

Document properties within PDF files and technical reports

These metadata provide independent verification of creation dates, authorship context, and the chronological sequencing of project development between 2008 and 2010.

Where metadata was unavailable due to file conversion, scanning, or archival limitations, dates have been cross-referenced against structural calculations, fabrication records, and contemporaneous publications.

References

• Sheena, N. (2017). Deflection, stress distributions and modes of failure of cellular beams (Doctoral thesis, The University of Manchester). Research Explorer, The University of Manchester. https://research.manchester.ac.uk/en/studentTheses/deflection-stress-distributions-and-modes-of-failure-of-cellular-/
• Nguyen, Tran-Hieu, and Vu Anh Tuan. Weight Optimization of Composite Cellular Beam Based on the Differential Evolution Algorithm. Journal of Science and Technology in Civil Engineering (STCE) – NUCE, vol. 12, no. 5, 2018. Figure 1, “Manufacturing of Cellular Beams.” Available via ResearchGate.
• Panedpojaman, P. (2012). Buckling analysis for web post of cellular beams. In Proceedings of the 10th International PSU Engineering Conference (14–15 May 2012), Prince of Songkla University, Hat Yai, Thailand.
  
  Panedpojaman, P., Thepchatri, T., & Limkatanyu, S. (2014). Novel design equations for shear strength of local web-post buckling in cellular beams. Thin-Walled Structures, 76, 92–104. https://doi.org/10.1016/j.tws.2013.11.007
• New Steel Construction. Vol. 13, no. 2 (February 2005). New Steel Construction Magazine. https://www.newsteelconstruction.com/wp/wp-content/uploads/digi/2005pdf/0502NSCFeb05.pdf
• Holmes, Andrew. (2007). Structural Beam with Openings. US Patent Application US20070272342A1.
• Structural calculation report, 9 December 2008
• B.S.Y. Construction fabrication quotation, 24 December 2009
• Chagapon Tipsuwan. SlideShare Profile. SlideShare. https://www.slideshare.net/chagapon?tab=about (accessed 14 May 2026).