Seawater intrusion (SWI) is one of the most challenging and widespread environmental problems that threaten the quality and sustainability of fresh groundwater resources in coastal aquifers. The excessive pumping of groundwater, associated with the lack of natural recharge, has exacerbated the SWI problem in arid and semi-arid regions. Therefore, appropriate management strategies should be implemented in coastal aquifers to control the impacts of SWI problems, considering acceptable limits of economic and environmental costs. The management of coastal aquifers involves the identification of an acceptable ultimate landward extent of the saline water body and the calculation of the amount of seaward discharge of freshwater that is necessary to keep the saline–freshwater interface in a seacoast position. This paper presents a comprehensive review of available hydraulic and physical management strategies that can be used to reduce and control SWI in coastal aquifers. Advantages and disadvantages of the different approaches are presented and discussed.

A series of experiments were carried out to investigate the behavior of cement-stabilized fiber-reinforced clay with different cement and fiber contents. Three groups of tests were conducted, on: (1) reinforced samples with four different fiber contents (0.5%, 0.75%, 1% and 1.25%); (2) cement-stabilized samples with three different cement contents (5%, 8% and 10%); and (3) cement-stabilized, fiber-reinforced samples with the same fiber contents as the uncemented reinforced samples. Unconfined compression tests (UCT) were carried out on the uncemented samples. These UCT tests were also conducted on the cement-stabilized samples with and without fiber inclusions after 3, 7, 14 and 28 days of curing time. The results indicated that the inclusion of fibers within uncemented and cement-stabilized soil caused an increase in the unconfined compressive strength and axial strain at failure, and changed the brittle behavior of the cement-stabilized soil to a more ductile behavior. It was also shown that the mechanical characteristics of the soil–cement–fiber mixtures are functions of fiber content and curing time.

In this paper, a new genetic programming (GP) approach for predicting settlement of shallow foundations is presented. The GP model is developed and verified using a large database of standard penetration test (SPT) based case histories that involve measured settlements of shallow foundations. The results of the developed GP model are compared with those of a number of commonly used traditional methods and artificial neural network (ANN) based models. It is shown that the GP model is able to learn, with a very high accuracy, the complex relationship between foundation settlement and its contributing factors, and render this knowledge in the form of a function. The attained function can be used to generalize the learning and apply it to predict settlement of foundations for new cases not used in the development of the model. The advantages of the proposed GP model over the conventional and ANN based models are highlighted.