Sustainable development in urban construction

When faced with industrial waste, what should we do? Burning? Dumping? Or perhaps, repurposing? As urban areas keep growing, the innovative repurposing of industrial waste emerges as a groundbreaking approach for urban construction.

Generally, most types of industrial solid waste are directly burned or buried in landfills, which is harmful to the existing ecological environment. In this respect, the exploration of beneficial reuse of waste materials in geotechnical engineering has been investigated as a potential solution and has achieved significant progress to reduce waste and conserve resources.

Expansive soils, which are notorious for their low bearing capacity and high compressibility, often occur cracking in civil infrastructure over time. This study delves into the potential of reusing waste glass powder, a commonly discarded material, as a valuable additive for geotechnical engineering to mitigate desiccation-induced cracking, and pose the question: What if the cities of tomorrow were built from the discarded materials of today?

Expansive Soil — Innovative Stabilization with Glass Powder for Sustainable Construction

The schematic set-up is shown in Fig. 2. Temperature of 30 ℃ and relatively humidity of 75% was considered. Soil samples without reinforcement were used as control, soil samples mixed with glass powder were used for testing. The prepared soil specimen was cast into a round (inner diameter = 75mm, inner thickness = 8.4mm) container crafted from stainless steel. Subsequently, the specimen was placed in the same environmental chamber (Fig.1) to control and maintain environmental conditions. The images of soil surface cracking during desiccation were captured in a 15-minute interval. The whole process was performed for a period of 18h.

Why recycled glass powder?

Given its high durability and appropriate strength along with environmental factors, recycled glass powder that is typically sourced from post-industrial glass waste has been implemented as a sustainable approach in expansive soil stabilization. Some of the benefits are listed below:

Environmental Sustainability: reduce the demand for virgin raw materials and the energy required for glass production. This contributes to sustainability and reduces landfill waste.
Cost-Saving: reduce material expenses and transportation costs, as well as potential incentives for sustainability practices.
Long-Term Durability: reduce the risk of soil erosion, thereby increasing the longevity of infrastructure using treated soils.
Versatility: can be used in a variety of geotechnical engineering applications, including road construction, embankments, foundations, and retaining walls.

Key Learnings

1. From Fig.3, when adding recycled glass powder, CIF of the soil sample will decrease.
2. From Fig.4, by adding recycled glass powder, max internal crack width will decrease significantly.
3. From Fig.5, soil sample with recycled glass powder can effectively mitigate the desiccation cracking.

In conclusion, the utilization of glass powder makes it a viable and sustainable approach for mitigating the challenges in geotechnical engineering applications.