Numerical investigation into the effect of various surcharge loadings on propped wall excavations and embankments

Several guidance and formulation have been developed in the literature to account for the analysis of external surcharges adjacent to a propped excavation but less attention has been paid to the presence of sloping ground or embankments. However, CIRIA C760 states that the actual ground profile should be modelled and analysed as a series of surcharge loading over the extent of the active side of the wall. In this research, two braced excavation models were analysed of which one was the actual ground profile and the second with a series of surcharge loading representing the embankment adjacent to the excavation. The accuracy, efficiency, and conservation of the proposed approaches were examined on a propped cantilever wall excavation using a finite element geotechnical analysis software PLAXIS 2D. The models were analysed and examined in terms of the bending moment and deflection of the diaphragm wall and the prop load, the model with the actual ground profile was also investigated for any thrust load on the support system should the embankment or sloping ground fail in shear. The results were presented, and comparisons were made. Merits and advantages of the proposed numerical approach were discussed

Effects of various surcharge loading conditions on the stability of soil slopes

The stability of soil slopes is a theme which has great significance within the field of civil engineering, this paper will focus on the analysis of soil slopes under varying surcharge loads. There are two main methods used in the analysis of soil slopes the first is the most commonly used method, the limit equilibrium method (LEM) and the second is a finite element method (FEM) which is becoming more commonly used due to three-dimensional analysis aspect. It is suggested by [1] that the factor of safety is greater for three-dimensional analysis compared to that of two-dimensional analysis. As the accuracy of software packages continues to improve (FEM) will be more commonly used by civil engineers. In this study both analysis methods are used to analyse the effects on various surcharge loading conditions on the stability of soil slopes. By using two different approaches to the analysis of different surcharge conditions, two sets of data are produced both of which can be compared to validate the work. As this topic is widely studied previous papers with a similar research question where used as reference to compare results [2, 3]. The purpose of this study is to highlight the importance of understanding the effects of surcharge loading, it can be seen from previous studies that the focus is generally based on other factors such as the cohesion of the soil, the slope angle, the friction angle and the soil parameters. Whilst they are all individually important, the surcharge loading conditions are often neglected never investing the effects different loads would have on the stability of the soil slope. This shows a gap in the current field of study which this paper will investigate

Microwave Vacuum Drying Characteristics of Noni Fruits (Morinda Citrifolia L.) and Their Effects on Scopoletin Content

The main objective of this study was to investigate microwave-vacuum drying characteristics of Morinda citrifolia fruit slices and drying effects on Scopoletin content. A laboratory microwave-vacuum dryer was designed and fabricated and preliminary tests were conducted to ensure that its operation is satisfactory. M.citrifolia fruit slices were dried under different drying techniques such as: microwave-vacuum drying, microwave drying (without applying vacuum) and sun drying. Microwave-vacuum drying of M.citrifolia fruit slices were carried out at three levels of microwave power; 180, 300 and 450W and four levels of absolute pressure; 91 kPa, 86 kPa, 71 kPa and 41 kPa, whilst, microwave drying was conducted at atmospheric pressure (101 kPa). Drying was performed in two microwave application namely pulsed and continuous. In pulsed microwave drying mode, the magnetron was alternatively switched on and off in order to achieve desired pulsing ratio. The magnetron was switched on for 30 s and switched off for 150 s, corresponding to selected pulsing ratio of 6. M.citrifolia fruit slices having initial moisture content of about 5-6 g water/ g dry matter were dried to final moisture content of approximately 0.5 g water/ g dry matter within 10 to 252 min depending on microwave power, vacuum condition and microwave heating mode. For continuous microwave heating mode, the drying time was within 5 to 45 min, while for pulsed microwave heating mode it was within 33 to 198 min. Higher microwave power level and lower pressure increased the drying rate. The result shows that even though pulsed microwave heating mode was more time consuming overall, but total power-on time was about the same as continuous microwave heating mode; however, in pulsed microwave heating mode drying took place at lower product temperature. Page equation was most satisfactory to describe thin-layer drying characteristic of M.citrifolia fruit slices among the three tested thin-layer drying equations, with lower reduced chi-square X2 and RMSE and higher value for R2. Scopoletin was extracted from fresh and dried sample by solvent method using methanol and spectrofluorometric method was used for its determination. The Scopoletin content retention of M. citrifolia fruit slices dried under different drying techniques was evaluated and was found to be within 5 to 53%. In pulsed microwave heating mode, drying at atmospheric pressure resulted in higher Scopoletin content reduction with microwave power set at 450 W power level (20%); however, in continuous microwave heating mode at the atmospheric pressure, the lowest microwave power of 180W resulted in higher Scopoletin content reduction (51%). The reason for this, is due to longer drying time required at lower microwave power level, and higher temperature achieved due to longer power-on time during continuous microwave heating mode compared to pulsed microwave heating mode

Freezing characteristics of rain water drops with different solutes and their implications on anomalous ice crystal concentration in clouds

In an attempt to examine the probable cause for the reported anomaly between the ice crystal-and ice nucleus concentrations in clouds, the authors have carried out laboratory experiments on the freezing of rain water drops, under various conditions of temperature, with various solutes. Sulphates, when present in adequate concentration, have been found to accelerate remarkably the process of ice-formation in the drops. The contrast noticed has been greater at warmer temperatures. The ice-forming ability of silver iodide has also improved remarkably in the presence of sulphates. Chlorides, on the contrary, not only decelerated natural ice-formation in the drops but also deactivated silver iodide. Based on certain consideration

The Judge's Understanding of Iwad (Living Hadith in Palembang Religious Court)

This study aims to understand the perception of the Palembang Religious Court Judges about Iwad Khulu 'which originated from the Hadith. The results of this study indicate that there are two typologies of understanding of Iwad Khulu', both of theme are textual understanding and contextual understanding. According to the understanding of textual type, iwad must be understood to arise as a result of khulu 'because the husband violated the ta'lik talak  so that the wife filed for divorce by paying a ransom in the form of money in the amount of ten thousand rupiahs according to the provisions in The PMA Number 2 of 1990 concerning Obligations of Marriage Registrar, through regulations this Judge no longer takes other considerations. Whereas the contextual type understands that Iwad Khulu 'depends on the type of khulu',when it khulu' due to violations of the ta'lik talak, the iwad depends on the provisions of the Ministry of Religion, while the khulu' purely  caused by a reason other than the violation of the ta'lik talak then the considerations are proof, wife's ability and the principle of justice

Conditions governing drop freezing at warm temperatures

In an attempt to investigate conditions under which ice crystals can form at comparatively warm temperatures in supercooled regions of a cloud, the scope of experiments on drop freezing, previously undertaken by the authors, has been enlarged. The results of the present extensive series of experiments have confirmed that supercooling drops, when subjected to evaporation, freeze more readily due to what has been called the “dynamic effect” of evaporation. When sodium sulphate was added to the drops in arbitrary concentration, their freezing probability also showed a significant inctease. These findings indicate that, in supercooled regions of a cloud where prevailing conditions are similar to those of the reported experiments, the ice crystal concentration should be two to three orders of magnitude higher than the existing ice nucleus concentration

A numerical technique for simulation of cloud seeding experiments

Two numerical cloud seeding experiments, using historic rainfall for the Deccan plateau region in Maharashtra state, were performed adopting different simulation techniques. The data used consisted of 1-day total rainfall for the 5-year period 1951-55. A double-area cross-over design with area randomisation was adopted. The first experiment, EXP-TR, was based on the simulation technique of Twomey and Robertson which involves about 100 hr of Robotron EC-1040 computer time. The second experiment, EXP-MMM was based on a different simulation technique proposed in the present study. The results of EXP-TR and EXP-MMM have shown close agreement. The numerical simulation technique of EXP-MMM is more promising for the following two reasons: (i) the computational time is reduced by about an order of magnitude without compromising the scientific value of the results, and (ii) a direct estimate of the lower limit of the double ratio value which can be detected at 5 level of significance is defined. The results of the two numerical experiments suggested that, for the Deccan plateau region, 15 and 20 increases in rainfall due to seeding could be detected with 80 or more probability in 5 years

Numercial simulation of cloud seeding experiments in Maharashtra state, India

Two numerical cloud seeding simulation experiments of 5-, 8- and 10-years duration, with a double area cross-over design and area randomization, were performed using historic rainfall data for the Deccan plateau region in Maharashtra state. The first numerical experiment (EXP-TR) used the simulation technique of Twomey and Roberstson (1973), second (EXP-MMM) used different simulation technique proposed in the present study. The results of the two numerical experiments have agreed closely. The EXP-MMM technique not only reduces computational time by an order of magnitude but also defines the exact lower limit for the double ration value which can be detected at 5 per cent level of significance. The results of the numerical experiments suggest that 15 and 20 percent increases in rainfall due to seeding in Maharashtra could be detected, with 80 percent or more probability, in 5 years. In a 10-year experiment the probabilities of detecting 5 and 10 percent increases in rainfall due to seeding are 27 and 65 percent, respectivel