Mechanical joints

Here’s a detailed look at mechanical timber joints—especially traditional types like dovetail and mortise-tenon—and their structural and cultural significance:

🪚 1. Mortise and Tenon Joint

A classic timber connection where a tenon (tongue) fits into a mortise (slot):

• Used for beam-to-column or frame-to-panel connections

• Offers strong axial and shear resistance

• Can be fully concealed for aesthetic purposes

• Variants include:

  • Through mortise-tenon

  • Blind mortise-tenon

  • Wedged mortise-tenon

  • Haunched mortise-tenon

🔗 Analysis of mortise-tenon joints in traditional timber buildings – ResearchGate

🧩 2. Dovetail Joint

A specialized mortise-tenon variant with an inverted trapezoid shape:

• Provides excellent resistance to pulling forces

• Common in roof trusses, furniture, and palace-style timber frames

• Functions as a semi-rigid connection with rotational moment capacity

• Often used in beam-column joints in Chinese, Japanese, and European timber architecture

🔗 Rotational behavior of dovetail joints – Journal of Wood Science

🧪 Mechanical Performance Insights

• Rotational stiffness and bearing capacity depend on:

  • Geometry of the joint

  • Precision of fit

  • Wood shrinkage and creep over time

• Looseness in joints can reduce performance, but small gaps (≤2 mm) have minimal impact

• Dovetail joints can transfer both tension and compression, making them structurally versatile