Flexural and Compression Superiority of Sewage Sledge Ash Concrete

The sustainability of environment has become a global issue, and several researches have been conducted in order to uncover possible and trustworthy solutions for lowering the problem and increasing one's quality of life. Wastewater treatment produces sludge, which is an unavoidable byproduct. Landfilling, ocean dumping, and spreading over reclaimed territory are all common ways of disposal. However, these popular sludge disposal methods represent a significant dilemma since they can pollute the environment, including the air, land, and water. Since sewage sludge can be treated to produce sewage sludge ash (SSA), which has the potential to replace certain percentages of cement, studies on sewage sludge have been popular in recent years. Many studies have been done to use the SSA in lightweight concrete, bricks, and aerated concrete because nations like Spain and the United Kingdom have problems disposing of sewage sludge. This study focuses on the flexural and compression strength of the sewage sludge ash (SSA) concrete for 3, 7 and 21 days of curing relatively to its density. In this study 10 percentages of SSA was used as a replacement to cement and fine aggregates. The flexural strength of concrete for cement replaced with SSA was lower than the control sample but it has an higher early flexural strength. The flexural strength of concrete for fine aggregate replaced with SSA was higher compared to the control sample. Comparatively, the compressive strength of concrete when SSA used as combination of cement and fine aggregate replacement also give higher value compare to control sample

Integral bridges: modelling the soil-structure interaction

Integral abutment bridges, also known as integral bridges, have become one of the most common types of joint-less bridge construction, certainly over the last three decades. Their principal advantages are derived from the elimination of expansion joints and bearings, making them a very cost-effective system in terms of construction, maintenance, and longevity. The elimination of joints from bridges creates a significant soil-structure interaction behind the abutment and the piles generating an interesting problem since the response of the different elements of the integral bridge are interdependent. This research project used numerical analyses to investigate the complex interactions that exist between the structural components of the stub-type integral abutment bridge and the backfill soil. Where possible, these results were validated with existing field data. A literature review was conducted to gain an insight into the behaviour of integral abutment bridges, particularly the soil-structure interaction of integral bridges. To gain a better understanding of the behaviour of integral abutment bridges and their interaction with the backfill soil adjacent to the abutment and the piles, particularly due to thermally induced movement/loads, a 2D finite element analysis was performed on a typical integral abutment bridge using OASYS GSA and OASYS SAFE. The results from this research are believed to help answer two of the most debated issues with respect to stub-type integral abutment bridge-soil interaction analyses. Firstly, it is clear, and now possible, that a reliably accurate soil profile is used in the analysis/design. The Mohr-Coulomb soil model was found to realistically represent the soil behaviour. Secondly, the research may suggest that cyclic movements / loads may not significantly influence the overall behaviour of integral abutment bridges. In addition, it was found that the development of earth pressure behind the integral abutment is significantly affected by the backfill soil properties and is a function of the integral abutment displacement. Limiting values for the abutment displacement, which induces maximum backfill pressure, have been suggested. The soil separation phenomenon (gapping) was also found to significantly affect the backfill/foundation soil-load relationship behaviour. Implications· of this research for practising engineers and recommendations for future research work are also included.EThOS - Electronic Theses Online ServiceGBUnited Kingdo