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There are around 10 major bridges are being under construction in the Nagapattinam Tiruthuraipoondi B.G railway line. These bridges are supported by pile foundations with varying founding depths depending up on the soil stratum. Bored cast in suit piles were cast and pile load tests were conducted at five locations for the estimated pile capacity (capacity was estimated as per IS 2911). Almost in all the locations, the pile load test were failed, which means the pile settlement was beyond the specified settlement under the test load. The failure was assessed and reported in this paper. The estimated pile capacity (design load) and test load (working pile load test) was 278MT and 417MT respectively. The pile has got yielded (settled) beyond 12mm, when the test loads of 220MT (which is 80% of the working load) in progress. The pile got settled around 25mm when the working load was in progress and finally reached to 38mm after 12hrs. After unloading, the pile has got rebound only 3mm, which motivate us to do the complete re-assessment of the soil strata in the study area. The forensic investigation on this failure has clearly evident that the failure had happen due to inadequate geotechnical investigation and improper pile installation. The cause will be discussed in this paper.

Increased urbanization causes traffic and parking issues especially in metropolitan cities like Karachi, London, Shanghai, etc. To accommodate parking issues for the vehicles mainly in urban areas (excavated) underground parking areas under or nearby high rise buildings are preferred. As a result of excavation, ground movements occur that have a major impact on structures, buildings, and utilities. The past research usually oversimplified surface structure as an equivalent elastic beam, which is unable to represent the behavior of a framed building realistically. In this study, the detrimental effects (i.e. crack pattern) on a two-floor RCC framed building founded on piles due to an adjacent excavation-induced ground movement are investigated. Elasto-plastic coupled-consolidation analysis was adopted. The hypoplastic constitutive model was used to capture soil behavior. It is an advanced model which is able to capture the soil unique features which are non-linear behavior, stiffness degradation (with stress, strain & path-dependent), and stress-strain dependent soil dilatancy. The concrete damaged plasticity (CDP) model was used to capture the cracking behavior in the concrete beams, columns and piles. It was revealed that the induced slope and tilting are not equal. Consequently, the frame was distorted. As a result, tension cracks were induced at the inner side of the column.

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