freeze-thaw failure of decorative rod connections on aluminum curtainwall facade

Freeze-thaw failure of decorative rod connections on a brand new aluminum curtainwall facade.  The  defect affected approximately 10,000 connections.

One of the chief reasons of weatherproofing failures of facades is the thermal stresses and associated movements in excess of  seals’ elastic capacity. This is particularly true for metal curtain walls, because of large discrepancies of thermal coefficients of materials involved in their construction.

Fatigue of metal components, and spalling of brick and stone facades caused by thermal cycles affect safety, because these components may fall from great heights. This was the case with the solid aluminum rods shown on the pictures, which were observed falling on sidewalks from 40-story+ skycraper, prompting the forensic investigation, while the building was still under construction.

Thermal stress imposed on the façade elements, self-shading, inadequate glass- insulation spacing, as well as freeze-thaw damage cause deterioration and inferior performance. This is why we provide thermal stress analysis of curtain walls and other facade components.

curtainwall rod thermal failure

The shop drawing of the inferior connection. Rainwater, which seeped into this connection,  expanded upon freezing, and consequently stripped the threaded connection .

3d Dimensional Thermal Stress Analysis

3d analysis of curtain wall allow for better engineering design.