In the present investigation, the geotechnical stability of the substructure of 100-year-old brick masonry rail bridges has been analysed numerically in the presence of nearby newly proposed concrete box bridges. Two different arch bridges (1273/1 and 1274/1) of Indian Railways (IR) have been considered in thisanalysis. Both bridges are made of brick masonry with different numbers of barrels. The numerical analysis has been performed using the finite-element (FE) method. The existing railway track between Kanpur and Jhansi, India, runs on these bridges, which were basically constructed by the British between 1888 and 1900. Therefore, the assessment of geotechnical safety and stability of such heritage bridges was of paramount importance from the IR point of view since the modern rail loading and other associated factors were changed significantly. Adetailed geotechnical investigation along with the plate load test was carried out at the respective bridge locations, and the results are reported in this paper. The distribution of the vertical stress and the settlement developed below the foundation of the bridges have been acquired from the FE investigation to judge the foundation safety against the strength and the serviceability perspective.

The motivation and scope of the present work are to investigate the interaction phenomenon of two closely spaced square plate anchors through physical modelling and validating it with the help of finite-element modelling. In the present study, different sizes of plate anchors are considered for studying their uplift behaviour when they are laid as single as well as in a group of two symmetrical anchors. A large-scale model testing facility has been developed and fabricated in order to perform the physical modelling. In physical modelling, poorly graded, dry Quartzanium sand is utilized as the foundation material. PLAXIS^3D, a finite-element software for geotechnical engineering, has been used to validate the experimental results obtained from the large-scale model testing facility. The effects of embedment depth and size of the anchor plate as well as layering in soil media are the parameters considered in order to determine the interaction factors with respect to the uplift capacity and displacement of anchors.