Need for Upgradation of Foundation Code for Highway Transportation Infrastructure (IRC:78-2014)-Paper

Paper

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The paper argues that IRC:78-2014, India’s highway-bridge foundation and substructure code, is outdated and inconsistent with newer IRC standards. While other bridge codes have adopted limit-state design, IRC:78 still uses working-stress methods, creating conflicts in design requirements and load combinations. The author recommends upgrading it in line with the rest of the code suite, using Eurocode 7 as a reference.<br /><br />The code’s scope should cover all highway structures, including underpasses, subways and footbridges, as well as buried structures and retaining systems. The paper identifies unclear or inadequate provisions concerning safe bearing capacity and overburden pressure, allowable settlement, pile and well-foundation design, liquefaction, uplift stability, pile-load-test acceptance criteria, and foundation depth near existing bridges. It also questions reliance on Lacey’s regime theory for scour estimates, noting that it omits important factors and may be unsuitable for some soil conditions.<br /><br />A major concern is the variable quality of geotechnical investigations in India. The author calls for detailed investigation and testing procedures, accreditation of investigation agencies, and quality standards for sampling and laboratory work. The code should also clarify design loads and combinations, add guidance for well-foundation ovalisation, and address liquefaction effects such as lateral spreading and pile response.<br /><br />To reduce contradictions, structural detailing provisions should be moved to the relevant material codes, and loading provisions to IRC:6. The paper concludes that modernizing IRC:78 is essential for safer, more economical and sustainable bridge foundations. It emphasizes that reliable ground data and construction quality are as important as analytical methods and design factors.

Keywords

IRC:78-2014

bridge foundations

limit-state design

geotechnical investigation

scour estimation

pile foundations

well foundations

liquefaction

foundation code modernization

Eurocode 7