First Exploratory Study on the Ageing of Rammed Earth Material

Area of Science:

• Construction Materials Science
• Sustainable Architecture
• Geotechnical Engineering

Background:

• Rammed earth (RE) construction is gaining traction globally due to its sustainable building attributes.
• Understanding the long-term performance and aging effects of RE structures is crucial for its wider adoption.
• Natural weathering significantly impacts building materials, necessitating studies on their durability over time.

Purpose of the Study:

• To evaluate the aging effects on rammed earth material after 22 years of natural exposure.
• To compare the mechanical properties of aged rammed earth walls with their initial state.
• To assess the feasibility of recycling aged rammed earth soil for new construction.

Main Methods:

• Mechanical characteristics of 22-year-old rammed earth walls were assessed using in-situ dynamic measurements.
• Laboratory tests were conducted on specimens cut from the aged walls.
• New specimens were manufactured using recycled soil from the aged walls to represent the initial state.

Main Results:

• Aged rammed earth walls exhibited reduced compressive strength and Young's modulus compared to the initial state.
• The study quantified the degradation of mechanical properties due to 22 years of weathering.
• Recycled soil from aged walls could be used to create new specimens, though their properties require further analysis.

Conclusions:

• Natural weathering over 22 years leads to a measurable decline in the mechanical performance of rammed earth walls.
• The findings highlight the importance of considering material aging in the design and longevity assessment of rammed earth structures.
• Recycling aged rammed earth soil is a viable option, contributing to the circular economy in sustainable construction.