Rock Slope Engineering

Some instability problems of cutting slopes were found along the main road alignment between Bandung and Majalengka, which is mostly lying on high slaking claystones. The main objective of this paper is to establish the findings of the study devoted to some slope instability problems in the claystones due to their propensity to slaking at selected locations of these cutting slopes. The slope performance analysis made during a field survey has obtained a plot of slope angles versus slope heights for the average stable conditions of the existing road slopes, which were then combined with the laboratory experiments of slaking tests, resulting in a standard chart to be suggested as a physical-based model for the cutting slope design. Based on this chart, the optimum slope design can be estimated directly from the input of lithological characteristics determined by simple and inexpensive field and laboratory tests.

Rock mass characterization requires a deep geometric understanding of the discontinuity sets affecting rock exposures. Recent advances in Light Detection and Ranging (LiDAR) instrumentation currently allow quick and accurate 3D data acquisition, yielding on the development of new methodologies for the automatic characterization of rock mass discontinuities. This paper presents a methodology for the identification and analysis of flat surfaces outcropping in a rocky slope using the 3D data obtained with LiDAR. This method identifies and defines the algebraic equations of the different planes of the rock slope surface by applying an analysis based on a neighbouring points coplanarity test, finding principal orientations by Kernel Density Estimation and identifying clusters by the Density-Based Scan Algorithm with Noise. Different sources of informationsynthetic and 3D scanned datawere employed, performing a complete sensitivity analysis of the parameters in order to identify the optimal value of the variables of the proposed method. In addition, raw source files and obtained results are freely provided in order to allow to a more straightforward method comparison aiming to a more reproducible research.

Dalam analisis stabilitas lereng terdapat banyak metode yang dapat digunakan, salah satu metode yang sangat popular hingga saat ini yaitu metode kesetimbangan batas. Metode kesetimbangan batas yang sering digunakan adalah metode Bishop, Metode Janbu dan metode Spencer.  Metode kesetimbangan batas juga sering disebet dengan metode irisan, Oleh karena itu penelitian ini dilakukan untuk menentukan faktor keamanan dengan metode Bishop, Janbu dan Spencer, dan mengetahui pengaruh irisan terhadap hasil faktor keamanan pada masing-masing metode.
Data masukan untuk analisis adalah data hasil uji sifat fisik dan uji mekanik batuan yang diperoleh dari hasil pengambilan conto di lapangan. Data masukan yang digunakan antara lain adalah bobot isi (γ), kohesi (c) dan sudut gesek dalam (). Geometri lereng yang digunakan pada penelitian ini adalah lereng tunggal yang disimulasikan dengan ketinggian 10 m dan sudut lereng 60°.
Jumlah irisan sangat berpengaruh pada hasil FK, semakin banyak jumlah irisan maka FK yang didapatkan juga semakin kritis. Pada metode Janbu dan Spencer jumlah irisan yang digunakan cukup 25 irisan karna penggunaan irisan > 25 irisan tetap menghasilkan FK yang sama, sedangkan pada metode bishop hasil FK selalu berubah setiap penambahan pada jumlah irisan. Hasil FK yang diperoleh divalidasi dengan program slide dan perbedaan hasil FK Slide dengan hasil FK manual diperoleh selisih 5%-10%.

Metode Bishop mengabaikan gaya gesek antar irisan dan kemudian mengasumsikan bahwa gaya normal cukup untuk mendefinisikan gaya- gaya antar irisan. (Bishop, 1955). Gaya normal di dasar dan tiap irisan ditentukan dengan menjumlahkan gaya- gaya dalam arah vertikal

(attenzione questa e' una versione obsoleta del Manuale - scaricare la versione piu' recente su researchgate  academia.edu  o diretamente dal sito web ufficiale www.ssp.eu )

SSAP2010 è il risultato di lungo lavoro di sviluppo iniziato ben 24 anni fa che ha visto la collaborazione di moltissimi utenti che hanno dato un notevole contributo allo stesso attraverso critiche costruttive e suggerimenti. La presente versione è il frutto di una evoluzione continua di un codice sorgente totalmente originale, scritto interamente dall’autore nel lontano 1991, culminata con la versione 4.0 (SSAP2010) nel dicembre 2010. La versione attuale SSAP2010 rel. 4.5.0 (2014) costituisce un ulteriore passo in avanti in attesa della futura versione 5.0 bilingue (italiano-inglese) che è pianificata per la metà del 2015.

Il Programma SSAP nasce dall’ attività di ricerca svolta nello sviluppo di algoritmi che consentono di ottenere una ottimale modellizzazione della configurazione geomeccanica e litostratigrafica dei pendii in terreni sciolti. Infatti, per valutare correttamente il grado di stabilità di un pendio, oltre che eseguire una corretta caratterizzazione geolitologica dell’area, è necessario tener conto delle eventuali disomogeneità presenti nella massa del pendio, soprattutto nei casi di marcata variabilità delle caratteristiche del terreno, quali ad esempio disomogeneità costituite da strati e lenti di materiali aventi diverse caratteristiche geomeccaniche, livelli di falda variabili, topografie irregolari, elementi stabilizzanti (muri, palificate, tiranti, geogriglie, geosintetici ecc.). Da un punto di vista geologico infatti tutti gli elementi di discontinuità costituiscono parte caratterizzante del pendio e come tali non possono essere trascurati a priori da operazioni di eccessiva generalizzazione del profilo stratigrafico e geomeccanico ricavato da campagne geognostiche. Talvolta invece per deficienze insite nei codici di calcolo esistenti o a causa dei tempi di calcolo, gli elementi di discontinuità rilevati vengono trascurati o semplificati eccessivamente, con conseguenze sulla attendibilità finale del processo di verifica.
In quest'ottica il codice SSAP è stato sviluppato mirando ai seguenti obbiettivi:
1. Possibilità di rappresentare adeguatamente tutte le discontinuità presenti nei pendii naturali o artificiali.
2. Evitare tutte le eccessive assunzioni semplificative sulla stratigrafia, sul profilo della falda, sulle superfici di scorrimento.
3. Seguire gli attuali standard di lavoro e le normative nelle verifiche di stabilità nei pendii in terreni sciolti e ammassi rocciosi fratturati;
4. Implementare nel software una serie di strumenti di calcolo tra i più avanzati e originali nell’ambito dei modelli di calcolo per le verifiche all’equilibrio limite.
5.Conseguire tempi di calcolo realistici anche per elaboratori anche di medie capacità.

Nearly 30 m high rock slope construction was necessary in soft rock condition during the construction of main road No. 21 in Hungary. Using rock mechanical laboratory test results, two different empirical rock classes (Slope Mass Rating-SMR and Q-slope) were applied to calculate the stability of the rock slope. For these calculations, the angles between the fracture geometries and the geometry of the rock cut should be taken into account to assume both very favourable and very unfavourable conditions. The analysis have shown that in unfavourable conditions the slope may be affected by sliding and a significant deterioration of the slope's rock material may occur due to weathering.

A number of guidelines for the field estimate of intact rock strength are available. Although all vary slightly in terms of the boundaries of the strength classes, they generally rely on reaction to a number of simple index tests. The errors and uncertainties associated with estimation of strength using these schemes are high and strength estimates need to be treated with caution. Undertaking point load index testing in the field is a useful tool that can provide data to augment field strength estimates and laboratory test data. Field point load index test data can be converted to an equivalent uniaxial compressive strength (UCS) but this relationship should be calibrated through twinned UCS and point load index tests. A case study is presented for an investigation in highly anisotropic banded iron formation of the Hamersley Province, West Australia. The relationship between UCS and point load index strength for the site is shown to be strength dependent. The calibrated field point load index test data is provides additional information on the variability of the rock strength that could not be captured by limited laboratory testing.

SSAP2010 is a complete freeware software for checking the stability of natural and artificial slopes or with reinforcing elements.  SSAP2010 provides users with a set of original tools able to perform in-depth stability checks using only rigorous and innovative methods based on the advanced Limit equilibrium method and innovative search engines able to find the critical surfaces associated to minimum Safety Factor (Fs). The Slope Stability Analysis Program (SSAP version 5.0 - 2020), is the first complete, and freeware,  application of LEM (Limit Equilibrium Method) numerical methods  implementing a series of characteristics and functions, not only  available today  in commercial software but with the addition of innovative algorithms and original methods..
SSAP has been developed during 29 years (1991-2020). All computational procedures have been developed starting from published papers on slope stability computational techniques in geotechnical literature in the last 60 years, and from original developments by the author.
Current SSAP release (5.0 - 2020) contains many new tools and original algorithms in order to obtain more reliable Fs values and using a more general approach to LEM  (Advanced LEM) with respect  the past.  An Important integration is given with the adoption of original and innovative numerical methods and of a hybrid methodology between LEM and finite element method (FEM), here called qFEM.
A Windows WIN 10 graphic interface and a series of software tools for  the slope model assembly,  graphic visualization and reporting, complete the software. https://www.ssap.eu.

Main SSAP2010 HIGHLIGHTS
Freeware software tool with large diffusion and use in Italy for professionals, students, researchers, and private and public companies.
29 years of development based on 100% original coding, testing, and continuous interaction with final users with the aims of software improvement.
Many original algorithms (e.g. sniff random search 3.0, and 2D map of local average Fs by the new hybrid LEM -FEM method).
Numerical stability control and its reliability analysis; groundwater and fluid pressure management module; reinforcement structures etc.
interactions with various type of structures: as geogrids-geotextiles, MSEW,MSE, gabions, piles, walls, ground anchors, anchored steel wire mesh.
Dynamic analysis by Seismic pseudo-static methods and displacemement method.
5 Failure criteria Mohr-Coulomb, Tresca, Generalized Hoek-Brown (non-linear), Barton-Bandis(1990) (non-linear), Liquefaction: Olson -Stark (2003)
Technical documentation on-line (still in Italian) and many real examples of application in natural and reinforced slopes.
Many applications in Italy, and some in México: case studies with high stratigraphic, geomechanics and hydraulic complexities.
Free download from the WEB: https://www.ssap.eu.
User’s license Full freeware for any type of final applications (profit and no-profit).

During the past centuries, more methods with many involved imperfections and limitations in various conditions suggested for slopes stability analysis specially based on different rock mass classification systems. However, RMi (rock mass index) classification system did not use for scrutinized assessments until now in accordance with its precise studies upon discontinuities system as joint characteristics, also block size as three-dimensional block volumes and intact rock strength to represent the rock mass uni-axial compressive strength. In this paper, for the first time, several empirical relations recommend only for the section RS06 in the block five of Sungun Copper Mine for 37° overall slope angle in fully drained conditions which presents some RMi applications in determining rock slopes safety factor in these situations to show multidimensional importance existence relations between factor of safety and RMi. Meanwhile, computed safety factors values from proposed equations compared with results of the limit equilibrium slope stability evaluation of SLOPE/W software. Using the earth's strength limit fundamental key parameter in offered formulas, which assays and indicates the major gravitational effects in slope stability procedures, increasing predictability of earth's materials behaviors that enabled us to calculate safety factor through RMi, simply, comprehensively and accurately in reasonable short-duration. Also, leads to better analyzing, showing moreover, understanding of the relationships between safety factor and RMi. Furthermore, this factor helps open new horizons and bridge between various sciences such as basis and applied physics, rock mechanics, rock engineering and engineering geology to indicating extended complicate correlations of all sciences' components that play role in the entire word wide. Research procedures in this article planned based on present mathematical relations via main properties of the slopes, earth and the universe. Low root-mean-square error, percent of variance, standard deviation and variation coefficient also great efficiency and correlation coefficient of calculated safety factor through new suggested empirical equations in its comparison with SLOPE/W results indicated high accuracy of proposed formulas.

SSAP2010 is a complete freeware software for checking the stability of natural and artificial slopes or with reinforcing elements.  SSAP2010 provides users with a set of original tools able to perform in-depth stability checks using only rigorous and innovative methods based on the advanced Limit equilibrium method and innovative search engines able to find the critical surfaces associated to minimum Safety Factor (Fs). The Slope Stability Analysis Program (SSAP version 5.0 - 2020), is the first complete, and freeware,  application of LEM (Limit Equilibrium Method) numerical methods  implementing a series of characteristics and functions, not only  available today  in commercial software but with the addition of innovative algorithms and original methods..
SSAP has been developed during 29 years (1991-2020). All computational procedures have been developed starting from published papers on slope stability computational techniques in geotechnical literature in the last 60 years, and from original developments by the author.
Current SSAP release (5.0 - 2020) contains many new tools and original algorithms in order to obtain more reliable Fs values and using a more general approach to LEM  (Advanced LEM) with respect  the past.  An Important integration is given with the adoption of original and innovative numerical methods and of a hybrid methodology between LEM and finite element method (FEM), here called qFEM.
A Windows WIN 10 graphic interface and a series of software tools for  the slope model assembly,  graphic visualization and reporting, complete the software. https://www.ssap.eu.

Main SSAP2010 HIGHLIGHTS
Freeware software tool with large diffusion and use in Italy for professionals, students, researchers, and private and public companies.
29 years of development based on 100% original coding, testing, and continuous interaction with final users with the aims of software improvement.
Many original algorithms (e.g. sniff random search 3.0, and 2D map of local average Fs by the new hybrid LEM -FEM method).
Numerical stability control and its reliability analysis; groundwater and fluid pressure management module; reinforcement structures etc.
interactions with various type of structures: as geogrids-geotextiles, MSEW,MSE, gabions, piles, walls, ground anchors, anchored steel wire mesh.
Dynamic analysis by Seismic pseudo-static methods and displacemement method.
5 Failure criteria Mohr-Coulomb, Tresca, Generalized Hoek-Brown (non-linear), Barton-Bandis(1990) (non-linear), Liquefaction: Olson -Stark (2003)
Technical documentation on-line (still in Italian) and many real examples of application in natural and reinforced slopes.
Many applications in Italy, and some in México: case studies with high stratigraphic, geomechanics and hydraulic complexities.
Free download from the WEB: https://www.ssap.eu.
User’s license Full freeware for any type of final applications (profit and no-profit).

In this study, it was aimed at evaluating the slope stability conditions in a residential area exposed to two landslides in the past by using two-and three-dimensional limit equilibrium analyses. Two separate, but interdependent, landslides were observed in the investigated area. In 1992 and 1994, two landslides occurred in the region after heavy precipitation and caused damages on the houses and infrastructures. An extensive field work was performed to obtain input parameters for the analyses. In addition, an unmanned aerial vehicle was flown to obtain a three-dimensional view of the landslide area for better understanding of the past failures. The landslides occurred in a flysch-type material representing complex geological characteristics. Hoek-Brown failure criterion and Geological Strength Index were chosen for the strength and visual definition of the geological unit. Since the landslide triggering factor was precipitation, the analyses were focused on the water conditions causing the failure. Sensitivity and back-analyses were performed to obtain the conditions of failure. It was revealed that a high pore pressure ratio was needed to trigger the landslides. However, the second landslide was failed with a lower pore water pressure and the current topography was determined to be on the edge of failure with a slight increase in the pore pressure ratio. In other words, the study area was still found to be prone to possible landslides in the future.

el cual está conformado por rocas antiguas, algunas sometidas a un alto grado de metamorfismo, por las intrusiones de varios plutones graníticos del Mesozoico. Ellas son, el "Neis de Bucaramanga (PDb)", el "Plutón de La Corcova (Rcl)", y el "Plutón de Santa Bárbara (Rcs)". Entre el k2 y el k5+600 la carretera se construyó en la zona media de la ladera, que tiene una pendiente promedia de 65°, en donde aflora roca sana, ligeramente meteorizada, con resistencias a la compresión inconfinada muy altas, El ancho promedio de la banca es de 5,5m, y de acuerdo con las indicaciones del INVÍAS, el ancho mínimo de la banca para pavimentar es de 6m, y no permitió la excavación de roca. Con el fin de lograr el ancho mínimo de la banca se decidió construir recalces de hormigón anclados sobre los cuales se apoyaron muros de contención de gravedad. En este artículo se describe el análisis que se realizó para determinar la estabilidad de dichos recalces anclados.

In this paper, a framework of generating a rockfall hazard map based on the existing rockfall database and GIS is described. Various factors have been incorporated into the logistic regression analysis, including geology, slope angle, slope aspect, and elevation. A total of 374 rockfall data are extracted from GEO reports from 1984 to 1998. The slope angle, slope aspect and elevation at each of these rockfall locations are generated using ArcGIS based upon the digital elevation model (DEM). In order to conduct a logistic regression analysis for the rockfall hazard, another 374 locations (or pixels in the DEM) without prior rockfall occurrence were selected evenly over the territory of Hong Kong. Correlations of rockfall occurrence with various factors were conducted using logistic regression through the use of SPSS .

، ‫ﻋﺒﺪاﻟﻤﺎﻟﻜﻲ‬ ‫آروﻳﻦ‬ 2 ، ‫ﻣﺴﻌﻮد‬ ‫اﺣﻤﺪوﻧﺪ‬ 3 ، ‫ﻗﺪﻣﻲ‬ ‫ﺣﺎﻣﺪ‬ 4 ‫زﻳﺴﺖ‬ ‫ﻣﺤﻴﻂ‬ ‫و‬ ‫ﻋﻤﺮان‬ ‫ﻣﻬﻨﺪﺳﻲ‬ ‫داﻧﺸﻜﺪه‬ ‫اﺳﺘﺎد‬ ، ‫داﻧﺸﮕﺎه‬ ‫اﻣﻴﺮﻛﺒﻴﺮ‬ ‫ﺻﻨﻌﺘﻲ‬ 1 ‫ﻋﻤﺮان‬ ‫ﻣﻬﻨﺪﺳﻲ‬ ‫داﻧﺸﻜﺪه‬ ‫ﭘﻲ‬ ‫و‬ ‫ﺧﺎك‬ ‫ﻣﻜﺎﻧﻴﻚ‬ ‫ارﺷﺪ‬ ‫ﻛﺎرﺷﻨﺎﺳﻲ‬ ‫داﻧﺸﺠﻮي‬ ، ‫ﺗﻔﺮش‬ ‫داﻧﺸﮕﺎه‬ 2 ‫داﻧﺸﺠﻮي‬ ‫ﻛﺎرﺷﻨﺎﺳﻲ‬ ‫ارﺷﺪ‬ ‫ﻣﻜﺎﻧﻴﻚ‬ ‫ﺧﺎك‬ ‫و‬ ‫ﭘﻲ‬ ‫داﻧﺸﻜﺪه‬ ‫ﻣﻬﻨﺪﺳﻲ‬ ‫ﻋﻤﺮان‬ ، ‫داﻧﺸﮕﺎه‬ ‫ﺗﻔﺮش‬ 3 ‫داﻧﺸﺠﻮي‬ ‫ﻛﺎرﺷﻨﺎﺳﻲ‬ ‫ارﺷﺪ‬ ‫ﻣﻜﺎﻧﻴﻚ‬ ‫ﺧﺎك‬ ‫و‬ ‫ﭘﻲ‬ ‫داﻧﺸﻜﺪه‬ ‫ﻣﻬﻨﺪﺳﻲ‬ ‫ﻋﻤﺮان‬ ، ‫داﻧﺸﮕﺎه‬ ‫ﺗﻔﺮش‬ 4 [email protected] ‫ﭼﻜﻴﺪه‬ : ‫ﺣﺴﺎس‬ ‫از‬ ‫ﻳﻜﻲ‬ ‫ﻣﻄﺎﻟﻌﻪ‬ ‫ﺳﺪﻫﺎ‬ ‫اﺣﺪاث‬ ‫در‬ ‫ﻣﺴﺎﺋﻞ‬ ‫ﺗﺮﻳﻦ‬ ‫روش‬ ‫ﺑﺮرﺳﻲ‬ ‫و‬ ‫ﭘﺎﻳﺪاري‬ ‫ي‬ ‫ﺷﻴﺮواﻧﻲ‬ ‫ﭘﺎﻳﺪارﺳﺎزي‬ ‫ﻫﺎي‬ ‫ﺑﺮ‬ ‫وﻣﺸﺮف‬ ‫اﻃﺮاف‬ ‫ﻫﺎي‬ ‫ﺳﺪ‬ ‫اﺳﺖ‬ . ‫ﻧﺮم‬ ‫از‬ ‫اﺳﺘﻔﺎده‬ ‫ﺑﺎ‬ ‫ﺗﺤﻘﻴﻖ‬ ‫اﻳﻦ‬ ‫در‬ ‫ﺣﺪي‬ ‫ﺗﻌﺎدل‬ ‫اﻓﺰار‬ slide ‫ﻧﺮم‬ ‫و‬ ‫ﻣﺤﺪودي‬ ‫اﺟﺰاي‬ ‫اﻓﺰار‬ plaxis ‫اﺳﺘﺎﺗﻴﻜﻲ‬ ‫ﺑﺮرﺳﻲ‬ ‫ﺑﻪ‬ ، ‫ﺷﺒﻪ‬ ‫ﺣﺎﻟﺖ‬ ‫در‬ ‫دﻳﻨﺎﻣﻴﻜﻲ‬ ‫و‬ ‫اﺳﺘﺎﺗﻴﻜﻲ‬ ‫ﻓﺮﺳﺎﻳﺶ‬ ‫دﭼﺎر‬ ‫ﻣﺤﻴﻄﻲ‬ ‫ﻋﻮاﻣﻞ‬ ‫اﺛﺮ‬ ‫در‬ ‫ﻛﻪ‬ ‫ﺳﻨﮕﻲ‬ ‫ﺷﻴﺮواﻧﻲ‬ ‫ﻳﻚ‬ ‫اﺷﺒﺎع‬ ‫و‬ ‫اﺷﺒﺎع‬ ‫ﻧﻴﻤﻪ‬ ‫و‬ ‫ﺧﺸﻚ‬ ‫ﻫﺎي‬ ‫ﻣﻲ‬ ‫ﺷﺪه‬ ‫ﭘﺮدازﻳﻢ‬ . ‫روش‬ ‫ﺑﺮرﺳﻲ‬ ‫ﺑﻪ‬ ‫ﺳﭙﺲ‬ ‫ﺷﻴﺐ‬ ‫ﻫﻨﺪﺳﻲ‬ ‫اﺻﻼح‬ ‫ﺟﻤﻠﻪ‬ ‫از‬ ‫ﭘﺎﻳﺪارﺳﺎزي‬ ‫ﻫﺎي‬ ، ‫ﺳﻴﺴﺘﻢ‬ ‫ﻣﻬﺎر‬ ‫ﻣﻴﻞ‬ ‫ﺗﻮﺳﻂ‬ ‫ﺑﻬﺴﺎزي‬ ‫ﻫﺎي‬ ، ‫و‬ ‫ﺷﻴﺮواﻧ‬ ‫ﺗﺴﻠﻴﺢ‬ ‫ﺑﺮاي‬ ‫ژﺋﻮﮔﺮﻳﺪي‬ ‫ﺑﺎﻛﺲ‬ ‫از‬ ‫اﺳﺘﻔﺎده‬ ‫ﭘﺮداﺧﺘﻪ‬ ‫ﺳﻨﮕﻲ‬ ‫ﻲ‬ ‫ﻣﻲ‬ ‫ﺷﻮ‬ ‫روش‬ ‫اﻳﻦ‬ ‫ﻣﻌﺎﻳﺐ‬ ‫و‬ ‫ﻣﺰاﻳﺎ‬ ‫و‬ ‫د‬ ‫ﻗﺮار‬ ‫ارزﻳﺎﺑﻲ‬ ‫ﻣﻮرد‬ ‫ﻫﺎ‬ ‫ﻣﻲ‬ ‫ﮔﻴﺮﻧﺪ‬ . ‫ﻛﻠﻴﺪي‬ ‫ﻛﻠﻤﺎت‬ : ‫ﺳﻨﮕﻲ‬ ‫ﺷﻴﺮواﻧﻲ‬ ، ‫ﭘﺎﻳﺪارﺳﺎزي‬ ، ‫ژﺋﻮﮔﺮﻳﺪ‬ ، ‫ﻓﺮﺳﺎﻳﺶ‬ ، ‫ﺣﺪي‬ ‫ﺗﻌﺎدل‬ .

Expansive soils have a high tendency of swelling and shrinking behavior depending on the seasonal variations; its volume increases during a rainy season and decreases during a dry season. Due to swelling and shrinking characteristics, it brings a major problem on geotechnical engineering structures and devastation to life. A road which is being constructed on expansive soils has no strength to carry a load and cannot resist any stresses. As it was reviewed from different literatures, the combination of lime and CSP stabilizes a problematic soil. The laboratory characteristics of subgrade expansive soils was investigated before and after the addition of lime and coconut shell powder separately and both mixtures to soils at different percentage, thus the properties of these materials was discussed and analyzed for how much they are effective in soil stabilization. Lime and coconut shell powder stabilization is the best option to control the volume changes of fine grained and expansive soils by adding appropriate percentage. Under this research the effectiveness (performance) of Lime and coconut shell powder was analyzed to determine the shear strength and swelling characteristics of expansive soils. The soil classification, Index Property, standard proctor compaction behavior, California Bearing Ratio (CBR), Optimum Moisture Content (OMC), Unconfined Compression Strength (UCS) and Free Swell properties were determined. The lime and CSP stabilized soil increases the value of CBR and UCS; the amount of the material added to the soil has a great impact for the strength being developed. Addition of lime and CSP are the most stabilizers used to reduce the plasticity of the soil and improves the strength of the soil and it brings a permanent modification with an easy manner. The optimum compressive strength of lime and CSP treated soil increases up to 6% and 5% respectively and starts to decreases as the amount of the material increases. The 8% of lime and 7% of CSP mixing together also increases the values of UCS. The increment of UCS due to lime and CSP is due to the initial increment of the moisture content. As the content of lime and CSP increases, the amount of moisture content increases and the dry density of the treated materials decreases due to the low specific gravity of lime and CSP relative to soil.

Questa guida è indirizzata a tutti gli utenti del codice SSAP che desiderano avere una panoramica completa delle possibilità di impiego offerte dal programma.
In particolare essa è rivolta ai professionisti e tecnici che possiedono già un certo grado di conoscenza delle metodologie, e delle problematiche connesse, di verifica di stabilità dei pendii costituiti da terreni sciolti e/o ammassi rocciosi fratturati, con o senza opere di rinforzo e stabilizzazione.
La guida si propone di fornire un riferimento completo a tutti gli strumenti di lavoro e alle procedure di calcolo implementate nel programma SSAP, sviluppate nel corso degli ultimi 25 anni dall’Autore.
Una quantità di tempo considerevole è stata impiegata per la stesura di questa documentazione, essendo essa parte integrante ed essenziale per garantire una buona qualità del software.
Come per un qualunque programma di calcolo per scopi tecnico-scientifici, soggetto ad un continuo processo di verifica e miglioramento, anche la documentazione interna ed esterna è soggetta a revisioni ed ampliamenti. Costante cura dell'autore sarà informare gli utenti di tutte le revisioni e migliorie apportate, affinché sia disponibile uno strumento di lavoro sempre al passo con gli standard attuali.
La versione più aggiornata dei questa guida è scaricabile, in forma di un file .PDF, dal sito ufficiale di SSAP: http://www.ssap.eu , che fornisce anche indicazioni sulla ultima versione ufficiale del software e sulla Licenza d'uso Freeware (ovvero gratuita) per privati e Pubbliche Amministrazioni, a partire dalla versione 4.0 (SSAP2010)..
Nel continuo processo di sviluppo di questo software sono di insostituibile aiuto i contributi degli utilizzatori del programma attraverso suggerimenti e critiche costruttive, che nascono dall'uso quotidiano e da applicazioni sopra casistiche reali. Al fine di garantire un trend continuo nel miglioramento della qualità del software applicativo sviluppato, l'intervento degli utenti sarà sempre assai gradito.
Si ringraziano pertanto tutti i numerosi utilizzatori che hanno fornito da più 20 anni, con i loro suggerimenti e tests, la possibilità di migliorare in modo continuo la qualità d questo software. Senza il loro contributo ciò non sarebbe stato possibile.

The geological strength index (GSI) system is dependent on the rock block volumes and the joint surface conditions. The weathering degree of rock slopes and their strength properties also depend on these characteristics. This study thus focuses on the use of the GSI system and the Hoek–Brown strength criterion to estimate the engineering parameters for weathered rock masses. Photogrammetric methods based on 3D surface models are used to obtain reliable data on the joint sets in rock slopes, instead of general site investigation using labor-intensive techniques. Photogrammetric surveys were conducted on weathered rock slopes in Gold Coast, Australia to obtain the joint spacing, orientation and roughness. The 3D models are then used to estimate the block sizes the joint roughness coefficients (JRC). The block volumes and JRC values were then used to estimate GSI values. Then parametric studies using the finite element method is conducted to investigate the stability of the slope using the GSI values.

An overview is given of the influence of weathering on engineering structures in and on natural materials. Some recently developed new ideas to incorporate weathering in design are discussed.  All natural materials near and sometimes also deeper below surface of the Earth are subject to weathering.  Notoriously difficult to forecast is the geotechnical behaviour due to future deterioration of the ground mass under influence of weathering. Weathering is a strongly local feature influenced by local circumstances such as local climate and weather, groundwater, and humans. Calculation methods and parameters used in design of engineering structures often do not properly anticipate the degradation of natural materials due to weathering. Preliminary failure, i.e. failure of the engineering structure before the end of the planned lifetime, may be the consequence. Slopes and tunnels start to raffle or may fail completely, and even buried foundations may be affected.

In the reliability analysis of slope, the performance functions derived from the most available stability analysis procedures of slopes are usually implicit and cannot be solved by first-order second-moment approach. A new reliability analysis approach was presented based on three-dimensional Morgenstern-Price method to investigate three-dimensional effect of landslide in stability analyses. To obtain the reliability index, Support Vector Machine (SVM) was applied to approximate the performance function. The time-consuming of this approach is only 0.028% of that using Monte-Carlo method at the same computation accuracy. Also, the influence of time effect of shearing strength parameters of slope soils on the long-term reliability of three-dimensional slopes was investigated by this new approach. It is found that the reliability index of the slope would decrease by 52.54% and the failure probability would increase from 0.000 705% to 1.966%. In the end, the impact of variation coefficients of c and f on reliability index of slopes was taken into discussion and the changing trend was observed.

The instability of lava deltas is a recurrent phenomenon affecting volcanic islands, which can potentially cause secondary events such as littoral explosions (due to interactions between hot lava and seawater) and tsunamis. It has been shown that Interferometric Synthetic Aperture Radar (InSAR) is a powerful technique to forecast the collapse of newly emplaced lava deltas. This work goes further, demonstrating that the monitoring of lava deltas is a successful strategy by which to observe the long-term deformation of subaerial-submarine landslide systems on unstable volcanic flanks. In this paper, displacement measurements derived from Synthetic Aperture Radar (SAR) imagery were used to detect lava delta instability at Stromboli volcano (Italy). Recent flank eruptions (2002-2003, 2007 and 2014) affected the Sciara del Fuoco (SdF) depression, created a "stacked" lava delta, which overlies a pre-existing scar produced by a submarine-subaerial tsunamigenic landslide that occurred on 30 December 2002. Space-borne X-band COSMO-SkyMED (CSK) and C-band SENTINEL-1A (SNT) SAR data collected between February 2010 and October 2016 were processed using the SqueeSAR algorithm. The obtained ground displacement maps revealed the differential ground motion of the lava delta in both CSK and SNT datasets, identifying a stable area (characterized by less than 2 mm/y in both datasets) within the northern sector of the SdF and an unstable area (characterized by velocity fields on the order of 30 mm/y and 160 mm/y in the CSK and SNT datasets, respectively) in the central sector of the SdF. The slope stability of the offshore part of the SdF, as reconstructed based on a recently performed multibeam bathymetric survey, was evaluated using a 3D Limit Equilibrium Method (LEM). In all the simulations, Factor of Safety (F) values between 0.9 and 1.1 always characterized the submarine slope between the coastline and −250 m a.s.l. The critical surfaces for all the search volumes corresponded to the 30 December 2002 landslide, which involved the lava delta and its surrounding areas. InSAR data provided the post-effusive deformation field after the 2007 and 2014 flank eruptions, whereas LEM results highlighted that the accumulation of lava flows on the prone-to-failure SdF submarine slope is the main cause of the detected lava delta deformation. Lava delta instability, measured also at Pico Island (Azores) and Kilauea volcano (Hawaii), is evidence of the broader spectrum of instability phenomena that take place in the coastal or submarine area of the flanks of the volcanoes. At Kilauea, past lava deltas have moved faster than the surrounding slope and the recorded movements relate only to the collapses of the deltas themselves, producing rapid mass wasting near the coasts. In contrast, at Stromboli and Pico, lava deltas move at the same velocity as the surrounding slope. In these cases, the displacement at lava deltas can be considered as a proxy for the deformation of submarine slides. There are very few studies dealing with lava delta deformation, thus, the analysis presented in this work will benefit the monitoring of submarine slopes in other prone-to-failure coastal or island volcanic systems which have the potential to generate tsunamis.

Rock mass characterization requires a deep geometric understanding of the discontinuity sets affecting rock exposures. Recent advances in Light Detection and Ranging (LiDAR) instrumentation currently allow quick and accurate 3D data acquisition, yielding on the development of new methodologies for the automatic characterization of rock mass discontinuities. This paper presents a methodology for the identification and analysis of flat surfaces outcropping in a rocky slope using the 3D data obtained with LiDAR. This method identifies and defines the algebraic equations of the different planes of the rock slope surface by applying an analysis based on a neighbouring points coplanarity test, finding principal orientations by Kernel Density Estimation and identifying clusters by the Density-Based Scan Algorithm with Noise . Different sources of information —synthetic and 3D scanned data— were employed, performing a complete sensitivity analysis of the parameters in order to identify the optimal value of the variables of the proposed method. In addition, raw source files and obtained results are freely provided in order to allow to a more straightforward method comparison aiming to a more reproducible research.

At the initial stage of tunnel design, the tunnel stability can be assessed by different design techniques which are broadly classified into three categories i.e. Mathematical Analysis, Empirical Methods and Numerical Analysis. Mathematical methods or closed form solutions are more precise methods; however, its use is limited to simple geometries and almost impossible for complex geometries due to complex and tedious calculations involved. In practice, Empirical and Numerical Methods are usually used for stability analysis of tunnels. It should be noted that it is not the replacement of final design. Empirical design methods use information about the structural geology and other rock mass properties as input that can be easily obtained at the initial stage of a project. Numerical Methods commonly require mechanical properties, especially strength and deformation of rocks. Numerical methods are also considered as precise due to provision of allowance for variable inputs and geometry ...

SSAP2010 is a complete freeware software for checking the stability of natural and artificial slopes or with reinforcing elements.  SSAP2010 provides users with a set of original tools able to perform in-depth stability checks using only rigorous and innovative methods based on the advanced Limit equilibrium method and innovative search engines able to find the critical surfaces associated to minimum Safety Factor (Fs). The Slope Stability Analysis Program (SSAP version 5.1 - 2022), is the first complete, and freeware,  application of LEM (Limit Equilibrium Method) numerical methods  implementing a series of characteristics and functions, not only  available today  in commercial software but with the addition of innovative algorithms and original methods..
SSAP has been developed during 31 years (1991-2022). All computational procedures have been developed starting from published papers on slope stability computational techniques in geotechnical literature in the last 60 years, and from original developments by the author.
Current SSAP release (5.1 - 2022) contains many new tools and original algorithms in order to obtain more reliable Fs values and using a more general approach to LEM  (Advanced LEM) with respect  the past.  An Important integration is given with the adoption of original and innovative numerical methods and of a hybrid methodology between LEM and finite element method (FEM), here called qFEM.
A Windows WIN 10 graphic interface and a series of software tools for  the slope model assembly,  graphic visualization and reporting, complete the software. https://www.ssap.eu.

Main SSAP2010 HIGHLIGHTS
Freeware software tool with large diffusion and use in Italy for professionals, students, researchers, and private and public companies.
29 years of development based on 100% original coding, testing, and continuous interaction with final users with the aims of software improvement.
Many original algorithms (e.g. sniff random search 3.1, and 2D map of local average Fs by the new hybrid LEM -FEM method).
Numerical stability control and its reliability analysis; groundwater and fluid pressure management module; reinforcement structures etc.
interactions with various type of structures: as geogrids-geotextiles, MSEW,MSE, gabions, piles, walls, ground anchors, anchored steel wire mesh.
Dynamic analysis by Seismic pseudo-static methods and displacement method.
5 Failure criteria Mohr-Coulomb, Tresca, Generalized Hoek-Brown (non-linear), Barton-Bandis(1990) (non-linear), Liquefaction: Olson -Stark (2003)
Technical documentation on-line (still in Italian) and many real examples of application in natural and reinforced slopes.
Many applications in Italy, and some in México: case studies with high stratigraphic, geomechanics and hydraulic complexities.
Free download from the WEB: https://www.ssap.eu.
User’s license Full freeware for any type of final applications (profit and no-profit). more details on SSAP technical Manual

41 500 simulated trajectories may potentially reach or cross this tract of the road. Based on these data, limited protection measures were suggested. The combined use of RPAS data, fused with ground GPS points, an accurate geomorphological survey, and terrain static and dynamic parameters from the literature allows fast, low-cost, and replicable rockfall numerical modelling useful for emergency response and adoption of proper protection measures. 1 Introduction Rockfall is a widespread natural hazard that poses continuous risk to the population in mountain areas worldwide (Whalley, 1984; Guzzetti et al., 2002). Due to the prevalent type of movement (free falling, bouncing, rolling, sliding), rockfalls are among the fastest and deadliest landslide type (Evans, 1997; Guzzetti et al., 2002). Rockfalls can be triggered by earthquakes, intense rainfall, frost weathering, wind, root growth, and even traffic (Guzzetti et al., 2004). The elements most exposed to rockfall hazard are transport corridors (Guzzetti et al., 2002; Budetta, 2004; Guzzetti et al., 2004), which often cross hazardous areas. In particular, rockfalls cause relevant damage to structures and infrastructures along secondary and minor transport networks, where adequate protection measures are not economically sustainable

This data set gives more than 11 years of temperature and displacements recorded on and in a limestone cliff. An ex- tensive presentation of the monitoring devices and interpre- tation of data is proposed in Gasc-Barbier et al. (2021) [1] . The hazard-monitored zone is a perched cave in a limestone cliffwhere apartof itsroofhad collapsed. Onitsroof, anun- stable beam reminds. A horizontal interlayer thinning from East to West, hanging to the roof of the cave at the west and east-clamped in the rock mass, delimits this remaining beam. Opened fractures can be observed all around the beam. In order to assess the remaining hazard, four fissurometers (F1 to F4) and a thermal probe were installed on the roof of the cave and two borehole extensometers (D1 and D2) were drilled perpendicular to the face of the cliff, above the cave, to understand the global behaviour of the rock mass. Mea- surements have been made between sockets embedded in the rock mass by means of INVAR wire measurements. Four bases made of two sockets each have been installed inside the cavity and five were put on the face of the cliffout- side and above the cavity. Measurements last between Jan- uary 2011 and June 2021. A 1.5-year gap is observed in the measurements because they were temporally stopped when