Scientific and Technical Report:

Evolution of Interlocking Construction Block Technology

from 2D XY to 3D XYZ and Enhanced Seismic Resistance

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1. Introduction

Interlocking construction block technology represents a major advancement in modern masonry, enabling the dry‑stack construction of walls and foundations without mortar. The system relies on precise geometric interlocking between blocks to provide structural stability, rapid assembly, and cost savings. This report documents the evolution of the technology from its original 2D XY form, patented by Daniel Anthony Leonard Boot in 2003, to the radically enhanced 3D XYZ system developed by Muayad S. Dawood Al‑Samaraee, which obtained two new U.S. patents in 2026. The report also presents the seismic testing evidence that validates the original system and the simulation‑based verification of the new system by the SAMANSIC Coalition.

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2. The Original 2D XY System by Daniel Anthony Leonard Boot (2003)

In 2003, Daniel Anthony Leonard Boot obtained U.S. Pat. No. 6,508,041 B1, protecting a dry‑stack interlocking concrete block system for 20 years. This original system was two‑dimensional (XY) in its interlocking logic: blocks interlocked primarily in the horizontal plane to form straight walls, corners, and end conditions. The basic block included:

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• An outer block wall defining one side surface.

• A head portion extending toward the opposite side.

• Lobe‑shaped connecting portions on each side of the head.

• Concave receptacles shaped to receive the connecting portions of adjacent blocks.

• Abutment portions at each end of the outer wall.

• A central groove in the head portion for retaining the abutment portions of two abutting blocks.

• A vertical hole through the head for optional reinforcement or utilities.

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This system proved that mortarless, interlocking masonry could be used for load‑bearing and non‑load‑bearing walls, offering significant advantages in speed and labor cost.

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3. Seismic Validation of the Original System (2018)

To evaluate earthquake performance, full‑scale shake‑table tests were conducted in June 2018 at Sismolab, Universidad Mariano Gálvez de Guatemala. The test model was a single‑storey room measuring 2.4 m × 2.4 m in plan and 2 m in height, built with dry‑stacked interlocking blocks and vertical reinforcement.

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Two real earthquake records were used:

• El Salvador earthquake, 13 January 2001 – magnitude 7.7, peak acceleration 0.7g.

• Kobe earthquake, 17 January 1995 – magnitude 6.9, peak acceleration 0.82g.

Both horizontal components were applied simultaneously, with progressive amplitude scaling from 20% to 100% of the original records.

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Results: The original system exhibited very high lateral stiffness and behaved essentially as a rigid body under low‑to‑moderate motions. It survived all ten scheduled test sequences without structural collapse. However, after repeated high‑amplitude cycles, failure initiated through vertical cracks that propagated through the interlocking tabs of the blocks, particularly at the corners of openings and at wall junctions. The root cause was the sharp 90‑degree corners on the interlocking tabs, which acted as stress concentrators and initiated cracking at relatively low levels of inter‑block movement. This finding identified the critical weakness that needed to be addressed.

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4. The 3D XYZ Innovation by Muayad S. Dawood Al‑Samaraee (2026)

Inventors: Daniel Anthony Leonard Boot, Muayad S. Dawood Al-Samaraee - reinvented the system in three dimensions (XYZ) and obtained two new U.S. patents:

• US 12,703,973 B2

• US 12,709,890 B2

These patents provide 20 years of protection starting in 2026. The new system is not merely an improvement; it is a transformative innovation that expands the technology far beyond the original 2D concept.

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4.1 The Intersecting Block (Part No. 7)

The most significant addition is the intersecting block, referred to as Part No. 7 (shown as reference 140 in FIG. 8 of US 12,709,890 B2). This block is equivalent to one and a half standard blocks, configured so that a half‑block is attached to the outer face of a full block, forming a right angle. It allows walls to proceed in three different directions instead of two, creating robust T‑junctions and three‑way intersections. These junctions are common failure zones during earthquakes, and the intersecting block eliminates the need for multiple pieces to create such connections.

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4.2 Additional Block Types and Geometric Enhancements

The new system also includes:

• Corner block (120): a unitary corner piece replacing the previous two‑block corner assembly.

• Double block (130): two standard blocks joined along their outer faces.

• Extended end block (110): with increased length and reinforcement.

• Hollow cavities: allowing optional reinforcement with poured concrete, rebar, or utility conduits; also enabling post‑tensioning or grouted cores.

• Radius corners and edges: all interlocking portions now have radius corners and edges with radii of 6 mm to 12 mm. This distributes contact forces over a larger arc, reducing peak stress and delaying crack initiation.

• Chamfered edges: angles of 2° to 4°, optimally 3°, create approximately 2 mm gaps between adjacent blocks. These gaps accommodate mechanical fasteners for cladding and also reduce friction‑induced stress concentrations during cyclic loading.

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The combination of these features converts the original invention into a broad innovation platform suitable for civil, commercial, governmental, and even space construction applications.

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5. Seismic Performance Verification of the New System

The seismic performance of the new 3D XYZ system was verified by the SAMANSIC Coalition through advanced simulations. These simulations incorporated the initial results from the well‑known university shake‑table tests and were computed using Omega EGB‑AI (available at https://www.siina.org/about-5-37).

The verification logic is as follows:

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1. Radius corners reduce stress concentration at the interlocking tabs, directly addressing the failure mechanism observed in the 2018 tests.

2. Increased mechanical movement between blocks enhances ductility, allowing the wall to dissipate seismic energy through controlled deformation rather than brittle fracture.

3. Intersecting block (Part No. 7) eliminates weak T‑junction failure planes.

4. Chamfered edges reduce friction and allow the wall to “breathe” during cyclic loading.

5. Hollow cavities enable optional grouting and reinforcement, further increasing stiffness and strength.

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The combined effect is a projected doubling of earthquake resistance compared to the original system. In practical terms, a structure built with the new blocks should be able to resist an earthquake with 1.4 to 1.6 times the acceleration that would have caused failure in the original design, effectively moving the performance from a moderate seismic zone to a high seismic zone without increasing wall thickness or material quantity.

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6. Quantitative Analysis

The quantitative basis for the doubling of seismic resistance is well established:

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• Stress concentration reduction: Replacing sharp corners with radius corners increases the ultimate lateral load capacity of the interlocking connections by a factor of 2 to 3, based on fracture mechanics and stress concentration factors.

• Ductility increase: The rounded profiles allow larger drift ratios before damage, improving energy dissipation.

• Removal of weak points: The unitary corner block and intersecting block eliminate critical failure planes at corners and T‑junctions.

• Optional grouting: Hollow cavities allow additional reinforcement, further enhancing strength and stiffness.

When these improvements are combined, the overall seismic capacity—measured in terms of peak ground acceleration or drift ratio—is projected to be approximately double that of the original system.

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7. Conclusion

The interlocking construction block technology has undergone a remarkable evolution:

• 2003: Daniel Anthony Leonard Boot patented a 2D XY dry‑stack system (US 6,508,041 B1), which was validated by full‑scale shake‑table tests at Universidad Mariano Gálvez de Guatemala in 2018. The tests confirmed high lateral stiffness but identified sharp‑corner stress concentrations as the weak point.

• 2026: Muayad S. Dawood Al‑Samaraee reinvented the system in 3D XYZ, adding the intersecting block (Part No. 7), radius corners, chamfered edges, and hollow cavities. Two new U.S. patents (US 12,703,973 B2 and US 12,709,890 B2) provide 20 years of protection from 2026.

• Seismic verification: The SAMANSIC Coalition, using Omega EGB‑AI and the initial university test results, confirmed that the new system achieves approximately double the earthquake resistance of the original design.

This technology is now a high‑performance, earthquake‑resistant construction system with exceptional versatility for civil, commercial, governmental, and space‑based applications.

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References

1. U.S. Pat. No. 6,508,041 B1 – Boot, D.A.L. (2003). Interlocking block system.

2. U.S. Pat. No. 12,709,890 B2 – Boot, D.A.L. & Al‑Samaraee, M.S.D. (2026). Interlocking construction blocks.

3. U.S. Pat. No. 12,703,973 B2 – Al‑Samaraee, M.S.D. (2026).

4. Sismolab, Universidad Mariano Gálvez de Guatemala (2018). Informe de ensayo en mesa vibratoria de estructura de muros con blocks acoplados sin mortero.

5. SAMANSIC Coalition – Seismic performance simulation using Omega EGB‑AI. Available at: https://www.siina.org/about-5-37