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The process of making phosphates fertilizer involves taking the soft rock phosphate and mixing it with sulphuric acid. This process creates a gypsum by-product (phosphogypsum). Although gypsum is a widely used material in the construction industry, most of the produced phosphogypsum is not processed around the world and is stacked into large piles over the land, especially near coastal areas, which raised concerns about their stability. Such a disposal scheme creates man-made slopes in the surrounding areas which are prone to failure, which represents a common challenge for engineers. A slope failure will lead to a significant risk not only to human lives and activities but to the topographic and geological location of the stacks. In this paper, the geotechnical properties of the phosphogypsum in Aqaba, Jordan are determined and embankment stability analysis is carried out, as the purpose of this study is to evaluate the phosphogypsum stockpiles’ stability, and therefore, avoid any possible environmental disasters. Limit equilibrium methods and finite element methods were utilized in the analysis of this study. The required topographic and geological characteristics were obtained during the site visits and the contour plot of each phosphogypsum pile was produced by the Jordan Phosphate Mines Company (JPMC). Several laboratory tests were conducted to estimate the geotechnical properties of the stacked material due to the limited information on the Jordanian Phosphogypsum characteristics. Based on the results of this study, the above-ground slopes for the stacking of Phosphogypsum in Aqaba were found to be stable under both static and earthquake loading. Therefore, this study proved that the disposal process of the current stockpiles in Aqaba is sustainably managed for providing stable stockpiles and that the process has a generally low environmental risk.

In this paper, rainfall droplet impact force is transformed into a measurable voltage signal output via the piezoelectric material direct effect utilized for sensing purposes. The motivating sensor is utilized to measure the peak impact forces of rainfall droplets for further analysis and processing. Constructing a sense for the impact force of rainfall droplets has great implications in many real-life applications that can provide vital information regarding the amplifications of the impact force of rainfall on soil erosion, and the impact on small creatures and plants, etc. The rainfall droplet is set to collide on a very thin aluminum plate with negligible mass that can be presented geometrically as an extended segment of the proposed sensing device. The proposed sensing device is composed of a bimorph simply supported composite-piezoelectric beam that buckles due to the effect of the rain droplets’ vertical impact force. The proposed device is designed for optimal performance in terms of the amount of voltage that can be measured. This is accomplished by having the first critical buckling load of the device as less than the impact force of the rainfall droplet. Accordingly, the well-known genetic algorithm (GA) automated optimization technique is utilized in this paper to enhance the measured voltage signal. A proof mass is added to the middle of the beam to amplify the magnitude of the measured voltage signal. The voltage signal is intended to be transferred to the PC via a data acquisition system. The rainfall droplets’ peak impact forces are obtained analytically due to the nonlinear behavior of the beam using the Euler–Bernoulli thin beams assumptions. The FE model using COMSOL 6.0 Multiphysics commercial software is used to verify the analytical results.

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