A comprehensive study on bearing behavior of cement–fly ash composites through experimental and probabilistic investigations

摘要

The present study directs its aim towards the potential application of cement-fly ash composites (CFC) as structural fill in civil engineering applications and therefore, providing a viable and sustainable solution to the problem of bulk utilization of fly ash. The influence of cementation on the mechanical and shear characteristics of CFC with different cement contents was examined through a set of laboratory investigations. The load-settlement behavior of CFC has been investigated through a series of small-scale laboratory plate load tests. Experimental results indicate a substantial impact of cementation and curing periods on the geotechnical characteristics and load-bearing behavior of the CFC. In the second phase of the study, a probabilistic investigation is presented to quantify the influence of uncertainty arising due to improper mixing and compaction of CFC on the bearing behavior of the same. For this, the nonlinear finite element model has been developed and duly validated with the experimental results. The relative influence of different input parameters on the bearing behavior of CFC has been investigated, adopting an efficient factorial design approach. An explicit functional relationship between the significant parameters and bearing behavior of CFC has been developed by multiple regression analysis. The Monte Carlo simulation technique was then employed to assess the influence of the variability of various significant random parameters on the probability of failure of footing on CFC.