Papers by Author: Chih Ta Tsai

Abstract: The role of 3R (Reduce, Reuse, and Recycle) in constructing the Eco-society or Eco-city has been comprehensively recognized and promoted worldwide over the past two decades. Nowadays, several hot issues such as the energy saving, CO2 reduction, and eco-society have received great attention. Approximately 40% of global energy is used in the construction and subsequent operation stage, while a large amount of construction waste is produced during construction and after demolition. In Taiwan, the government continuously makes great efforts to promote the development of green building materials produced with the recycling construction waste over the past decades. However, the recycling green building materials are not extensively accepted and used in the construction industry of Taiwan. The objective of this study is to propose a strategy for promoting the recycling green building materials through the investigation of “cradle-to-cradle” life cycle of construction products. The key factors lowering people’s impression and purchase behavior have been studied. The disadvantage of existing policy of government is also discussed and compared. Finally, the present study attempts to propose a feasible strategy to assist government to promote the utility of recycling green building materials.

Abstract: This paper shows that a new approach (i.e. cold-bonding technique) to recycle uncontaminated and innocuous lime sludge as coarse aggregates. The cold-bonding technique incorporates the principles of the cement chemistry and composite material to develop recycling coarse aggregates. Herein lime sludge was regarded as the main materials to produce recycling coarse aggregates, which meet the specifications of green building materials in Taiwan, using the cold-bonding technique instead of sintering method in light of the issues of reduction of waste, energy, and CO₂ footprint. The results show that the specific gravity (in the oven-dry state, OD) of recycling coarse aggregate is in the range of 1.20 to 1.23; the absorption capacity is in 40.0 to 44.6 %; the dry loose density (i.e. unit weight) is 811 to 837 kg/m³; the single particle compressive strength at 28-day is in the range of 17.8 to 20.4 MPa; the particle cylindrical crushing strength ranges from 27.9 to 33.8 MPa; other characteristics also satisfies ASTM C33. The developed recycling coarse aggregates could increase the reuse and recycling of lime sludge, reduce the energy consumption and CO₂ footprint, and diminish the impact on the environment and future generations.