Diagnosis and Assessment of Deep Pile Cap Foundation of a Tall Building Affected by Internal Expansion Reactions

Early deterioration of reinforced concrete foundations has been often reported in recent years. This process is usually characterized by an extensive mapping cracking on surfaces that results from several types Internal Swelling Reaction (ISR). In this paper, a real case study tall building with severe installed its deep discussed. Laboratory tests were performed drilled cores extracted pile cap block 19 years after the beginning construction. Tests to assess compressive strength, static and dynamic modulus elasticity, gas permeability, electron microscopy scanning find out primary mechanism responsible for observed during situ inspections. Chemical alterations materials cores, mainly due Delayed Ettringite Formation (DEF), which significantly affected integrity durability structure. Dynamic elasticity showed be better indicator damage induced ISR than strength. Procedures strengthen deteriorated elements using prestressing proved efficient strategy recover structural caps expansions ISR.