**9. Software for analysis of reinforced slope**

The objective in designing geosynthetic reinforced soil slope is to determine the required long-term strength and layout of the reinforcement apart from finding the critical failure surface. The layout and strength are interrelated rendering many possible solutions with the same level of stability but not necessarily having the same economics. Software facilitates the designer to reach an optimal solution apart from locating critical failure surface by using search techniques and by repeatedly performing the stability calculations for different failure surfaces.

Pockoski and Duncan [65] compared several Limit Equilibrium based software available based on features of program, ease of use, range of applicability, accuracy, and efficiency. These programs were rated as well considering accuracy of results, computation time, learning curve, time to enter data and complete an analysis, ease of reinforced slope design, ease of unreinforced data entry, time required to make graphical output Report -Ready and quality of output. Different software included for comparison are: UTEXAS4 & TEXGRAF4, SLOPE/W, SLIDE, XSTABL, WINSTABL, RSS, SNAIL, GoldNail. UTEXAS4 is a precise analysis tool but does not have graphic user interface. TEXGRAF4 is second part of UTEXAS software package and displays information and results of the UTEXAS4 search and generates file for use in CAD software. SLOPE/W having a graphic user interface is user friendly and versatile. Reinforcement inclusion in to the analysis is also graphical. SLOPE/W has Monte Carlo based probabilistic stability analysis option where by soil, porewater pressure and seismic coefficient can be entered with standard deviation. SLIDE is Windows based slope stability program and can search for a critical circular, non- circular or composite slip surfaces. XSTABL is an interactive program which can search critical circular surface. WINSTABL is windows-based program whereby geosynthetic reinforcement, anisotropic soil, seismic loads, etc. can be considered in the analysis. RSS is an interactive program and is capable of exhaustive search performed on reinforced slope. Circular, bilinear, bottom third and top third failure surfaces are considered. SNAIL is window based free software and permits use of seven different types of soils and uses force equilibrium on two and three-part wedge analysis. GoldNail is a very powerful and design program that is primarily meant for soil nail wall analysis.

SSAP release 5.0 (2020) software (https://www.ssap.eu) is a versatile free software and uses advanced limit equilibrium method and FE-LEM combination to get the critical Factor of safety. ReSlope is an interactive, design-oriented, program for geosynthetic-reinforced slopes. For a given problem including geosynthetic strength, reduction factors, and design safety factors, ReSlope produces the optimal layout (i.e., length and spacing) of reinforcement layers. ReSlope was specifically developed for geosynthetics. SVSLOPE, GeoStru, Oasys, ReActive, Secuslope are other software available for reinforced slope stability analysis.
