Environmental effects of using different construction codes applied to reinforced concrete beam designs based on Model Code 2010 and Spanish Standard EHE-08

摘要

Assuming specific behavior models, the variety of design codes currently used for the design of concrete beams inevitably results in different solutions, ensuring service during the whole expected lifetime with a maximum functional quality and safety. However, from a sustainable design perspective, such differences may have remarkable environmental impacts. This paper analyses if the approach of the newest design code, i.e., the Model Code, leads to a reduction in resource consumption and greenhouse gas emissions (GHG) over the life-cycle of concrete beams. To do so, a comparative analysis of the environmental impact of concrete beams was carried out depending on the reference code used for its design (i.e., EHE-08 or Model Code). The results show that the reduction of reinforcing steel is a basic objective to minimize the life cycle environmental impacts of concrete beams. Every country may have its own design codes and, thus, the reinforcing steel use can vary for structures subjected to the same loads and with equivalent structural reliability. Hence, regulations play a key role in the sustainability of construction assets. Conclusions depend on the beam length (L) and height (h) and characteristic compressive strength (fck). For short beams (4 m), the greater theh, the greater the reinforcement difference between the two codes. With regard to beams of 8 m, these differences can lead to varying steel and GHG savings, e.g., up to 5.0% with MC-2010 (h = 0.6 m andfck ≤ 35 MPa), almost 40% with EHE – 08 (h = 1.0 m and 35 MPa  fck ≤ 50 MPa) and more than 30% with EHE–08 (h = 0.6 m and 35 MPa  fck ≤ 50 MPa). For long beams (L = 12.0 m), steel consumption is 0.3–19% lower when the beam is designed with EHE-08, and this difference decreases asfckincreases.