Creating Shared Walue through the Supply Chain by Selected Use of Modern Microalloyed High Strength Structural Steels in High-Rise Buildings

摘要

High strength micro-alloyed steels have been widely and successfully used since the early to mid-1970s across many industrial sectors such as automotive, transportation and energy systems. The credentials in light-weighting, enhanced mechanical performance, economic and environmental savings are reasonably well established. However despite the pioneering work by Khan and Graham in 1961 establishing the basis for hollow thin walled framed steel tube concept and "no premium for height" approach, the use of modern high strength micro-alloyed steels in tall building structural systems has lagged behind when compared to other end applications.Through engagement of a supply chain involved in the design and construction of a high-rise building project in Mexico City (Reforma 509), one key area highlighting the limited usage of modern high strength steels was the conception within the chain itself to the financial / economic and environmental benefits that could be shared. This paper shows that significant savings in materials (up to 20%) are possible if higher strength steels (≥ YS 480MPa), such as those typically micro-alloyed with niobium, are employed and can be competitively tendered in the design and construction of high-rise building. The study considers the most appropriate elements types to benefit from the increase in steel strength, and compares the implications in cost, constructability, material saving and reduced carbon footprint (by l,000t CO_2) for the selected high-rise project. Importantly it provides a view to the value creation potential within the supply chain in order to accelerate greater acceptance of high strength steels in the construction of high-rise buildings and the attractiveness to high-rise projects in South East Asian countries.