Using steel slag concrete (SSC) as a pile material not only promotes industrial waste recycling but also improves ground conditions through its distinct hydrological and chemical properties. This study investigated the hydrological processes of SSC piles under no-load conditions, offering new insights into pile-soil interactions. A novel visualization test device was developed to continuously monitor water migration, pore water pressure fluctuations, and soil disturbance over six months. Macro-scale observations and micro-scale analyses were conducted to elucidate physical and chemical reactions at the pile-soil interface. Compared to ordinary concrete piles, SSC piles demonstrated superior expansion and drainage capabilities, characterized by enhanced radial and vertical water flow, increased surface porosity, and the formation of a distinct interface layer enriched with calcium carbonate and cementitious hydration products. These improvements facilitate effective water distribution and drainage while reinforcing the pile-soil bond, thereby contributing to a more robust composite system for ground improvement. This integrated approach and its findings offer valuable contributions to the broader field of soil-pile interactions by detailing the multi-scale mechanisms governing the hydrological behavior and interface evolution of composite foundation systems.

Expansive soils are found to be susceptible for seasonal moisture fluctuations and will undergo cyclic swell-shrink movements causing stability concerns for all the civil engineering structures which are being constructed on these soils, and particularly the lightly loaded constructions like single storied dwellings, canal linings, pavements, etc. The swelling behaviour of these soils is generally characterized either by the mobilized swelling pressure under constant volume condition or by an increase in volume with the release of swell pressure. The researchers all over the world have made efforts in developing some remedial solutions to control or reduce the potential damages by these problems. The use of recently suggested technique of piled footings and its extension to pavements resting on expansive soils is explored by conducting field investigations within N.I.T. Warangal campus. The present work deals with studying the efficiency of tension piles (granular anchor piles and concrete piles) in reducing the swell-shrink movements of model footings and pavement panels resting on these soils. For this purpose, field studies were made by constructing 13 numbers of square footings with varied dimensions (1, 1.5 and 2 m side) and 5 numbers of square pavement panels of 3.0 m side with and without these tension piles. The swell-shrink movements of all treated footings and pavement panels were compared with those untreated ones for evaluating the efficiency in reducing the swell potential of these footings and pavement panels. The maximum heave of footings and pavement panels provided with granular anchor piles reduces by about 91%, and it reduces by about 75% when they were provided with concrete piles.