bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contribution to the geomechanical stability of marble underground openings using backfill
Authors: Franqueira M Formoso , Paneiro G A 
Published: September 2021

AbstractA stability analysis on the possibility of using room and pillar underground mining method, in a marble quarry in Alentejo (Portugal) with backfill, is presented. Given the data provided by the laboratory tests over marble samples and in situ tests as well as a thoroughly geology acknowledgment of the area, a new excavation design was presented for the underground phase, using Finite Element analysis, where global and local stability is assessed. Moreover, the innovative idea, for marble underground quarries, was to contribute to the circular economy and the current environmental policies by making a use of the quarry’s waste rock, as the principal aggregate for a backfill material, that not only reduces the impact of wastelands in the surface but also acts as support for the newly excavated area leading to residual pillars recovery. Given this, an overview of the stress displacement is presented, and the main potential instability zones are assessed. The results are a quantitative contribution to the characterization of the rock mass for alternative ways of ornamental marble production in this region.
Sustainable development for underground mining of strategic industrial minerals: the geological and geotechnical modelling as a key factor. The case of the “Marmorino” mineral deposit (Sacile - NE Italy)
Authors: Gabriele P , Damiano A , Varrone D , Piovano V , Cravero M , Castelli E , Anselmi B 
Published: September 2021

Abstract
The growing industrial minerals demand, in the perspective of a sustainable development of mining activities, implies a strong orientation to underground operations in the near future. In complex geological areas, for the definition of a reliable 3D ore body model a methodological approach, aimed to improve geological and geotechnical model reliability allows a confident mineral deposit evaluation and a reliable mine design, or, in other terms, costs reduction, safety increase and mining project sustainability. The described method finds its maximum application in complex geological and structural contexts, such as the Valmadonna-Pedemonte “Marmorino” quarry.
Effect of thermal cycles on rock cliff deformation. Monitoring and interpretation
Authors: Villarraga C. , Vaunat J. , Virely D. , Gasc M. 
Published: September 2021

Abstract
Climatic actions are one of the factors controlling the evolution of slopes, this paper is devoted to a specific effect, relatively little studied, related to the effect of climate-driven temperature changes on rock massif deformation. The particularity of the study is to focus on permeable rocks and Temperatures varying in a range which discards freeze/thaw effects. Research has been carried out in relation with the analysis of the real case of a limestone cliff located in the Périgord region, the massif was highly instrumented, results show a slow cyclic accumulation of deformations with time, essentially synchronic with thermal cycles. An advanced constitutive model, specifically developed to capture rock degradation due to the differential expansion of the main minerals composing the rock, has been developed. It has been calibrated on experimental results obtained in the laboratory on block samples tested in a climatic chamber for a long series (several months) of daily thermal cycles. Deformation and shear wave velocity were monitored during the test. Model shows a good agreement with laboratory measurements.
A quantitative approach to predict tunnel overbreak based on the Q-system
Authors: Ekeberg R , Holmes H , Paraskevopoulou C 
Published: September 2021

Abstract
Overbreak can be a significant challenge in tunnelling and is usually assessed on a project-by-project basis. This paper attempts to quantify tunnel overbreak in jointed rock masses by producing a predictive model that practitioners can utilize at the preliminary design stage. Discontinuum numerical analysis of a circular-shaped tunnel is performed using the combined finite difference – discrete element method to generate a database of rock masses prone to overbreak. The Q-system, rock mass quality index, is used to classify the rock masses that are expected to overbreak in various tunnelling environments. The results are scrutinized to identify trends between overbreak and: i) Q, ii) average joint spacing and, iii) in-situ stress conditions. It is observed that overbreak increases when Q < 4 and is uniform when Q ≤ 4. A predictive model is generated through multiple regression analysis and can be used to identify and highlight the maximum likely overbreak or scenarios where overbreak is expected to occur.
Practice of the Doorstopper stress measurement method during the last 30 years in Italy
Authors: Guido S , Acerbis R , Sossi G 
Published: September 2021

Abstract
In Italy, during the last decades, most of the in situ stress measurements were carried a shallow depth, in existing geotechnical structures. In these cases, the stress measurements involves concrete or low disturbed rocks material; thus linear, elastic, non-fractured materials. For this reason the stress tests interpretation is straightforward and reliable. In these situations, since the early 90s, the Doorstopper technique became the most used stress measurement technique. It has proven to be effective and cheap. A collection of punctual tests can be interpreted with a suitable numerical model. The numerical model provide the interpolation of the punctual measurements and can give important information about the virgin stress field. After recalling the main features and improvements of the doorstopper method in the last 30 years, this paper illustrates two Italian cases. The first case is the Sparvo Tunnel (Bologna-Firenze highway) where was performed a massive measurement campaign made up of more than six hundred Doorstopper tests in two adjacent tunnels; the results of the two tunnel are compared; the 2d FEM model interpretation is discussed. The second case is a marble quarry in Alta Carnia (Udine): the Doorstopper and stress variation measurements were carried out and interpreted by means of a 2d FEM model, resulting in the definition of the natural stress field.
Effect of the lay distance of a stiff support on the applicability of the Convergence-Confinement method
Authors: De La Fuente M , Berro F , Khodr S , Taherzadeh R , Sulem J 
Published: September 2021

Abstract
The use of the classical ConVergence ConFinement (CV-CF) method which is a simplified tunnel design tool is very extended nowadays. A major limitation of this plane-strain approach is encountered when it is applied to the study of tunnels with a stiff lining near the tunnel face. Under this configuration, the pressure exerted by the ground over the lining can be underestimated. The reason stems from the fact that this method is not able to simulate the tridimensional arch effect taking place between the ground and the lining. To account for this ground-support interaction, some authors have proposed to enhance the classical CV-CF method by resorting the so-called implicit methods. However, these approaches still show some limits for very stiff lining. In this paper, the applicability domain of the existing CV-CF methods when applied to the design of full-face excavated circular tunnels with a stiff support system is discussed. The results of the ground-lining equilibrium state obtained with the plane-strain approaches are compared with the equilibrium state obtained with an axisymmetric numerical model which can properly capture the arch effect taking place at the vicinity of the tunnel face. A sensibility analysis with a focus on the support lay distance has been carried out. Finally, a simple chart that clarifies which CV-CF method is more adapted to each tunnel configuration is proposed.
Preliminary Investigations and the Financial Sustainability of Underground Project
Authors: Coli M , Martelli L 
Published: September 2021

Abstract
Tunnels upgrade connectivity and mobility, with an all-out venture cost that mostly depends on the financial support given by significant lenders. Financial sustainability is related to Risk and Sensitivity Analysis, which in turn depends the level of knowledge of the geology of the project site. The target of this paper is twofold: depict the cycle of i) a well define comprehension of the geo-related model and ii) represent the impact of geo-related uncertainties into the Risk and Sensitivity Analysis. Key elements for assessing the economic sustainability of the investment are here outlined. The undeniable degree of financing preliminary investigations because of high forthright expenses is regular for the vast majority of the underground and tunnel projects. However, there are additional risks such as the geological uncertainty mainly related to the robustness of the preliminary investigations. Significant investment is needed prior to arriving at solid comprehension of the geological model and the connected hazards. Geological uncertainties can be characterized into two significant classes: epistemic and aleatory. Fundamental investigations are normally scant and don’t cover the epistemic vulnerability related to the chosen tunnel alignment or underground facility location. For an underground infrastructure project, the geological uncertainty exerts the highest impact on the project and financial sustainability. Variables must be surveyed and contrasted with the assessed cost in order the project being eligible to some kind of financing. Depending on the result of the risk analysis, solutions can differ: i) withdrawal from the project or restructuration, ii) chances ensures, iii) dividing the risks between parties and phases, and more significant, iv) a powerful undertaking readiness. Last option being the most efficient method for risk mitigation however depends on fundamental examination by specialists. Blended finance presents a risk sharing approach.
Study of damage to rockbolts used in the foundations of protection structures against gravitational hazards
Authors: Bost M , Gaillet L , Fargier Y , Martin R 
Published: September 2021

Abstract
Fully grouted rockbolts are used to anchor protection structures against natural gravitational hazards. In recent years, contractors have observed a premature degradation of the steel bars of these rockbolts. In the dimensioning of a rockbolt, the choice of the steel bar is currently made only on its pure tensile strength. The objective of this study is to identify whether the degradations observed in situ are related to the metallurgical nature of the bar steel and/or the load conditions. 16 damaged rockbolts were taken from four different sites in the Alpine area. They were subjected to a metallurgical analysis and a supplementary analysis of their environment. In conclusion, it was underlined that the damages were due to a lack of knowledge of the effective loads transmitted by the snow-filled structures, but also to a lack of consideration of the deformation behaviour of the foundation. The loads applied to these rockbolt bars generated a bending depending on the nature of the surrounding ground. It has been shown that these loads can occur in successive jolts and with modification of their orientation in relation to the number of links between the rockbolt and the protection structure.
Water control for a rock-soil interface - infrastructure at a contaminated site
Authors: Fransson Â , Surendran P , Berg A , Lindqvist E , Risby L , Schleeh A , Tennby G , Wiklund H 
Published: September 2021

Abstract
The conceptual model of the rock-soil f(and future shaft) interface was confirmed (so far not rejected) using data from investigation boreholes. The location of a depression in rock (a likely deformation zone) was indicated and confirmed using borehole data. Wave-washed deposits (upper part of the stratigraphy) and a lower water-bearing strata (soil) coinciding with the depression are key water-bearing features in soil. The likely deformation zone is expected to be a key water-bearing feature in rock. Grouting design (curtain-and blanket grouting) and sealing of soil (jet-grouting and sheet-pile walls) focus on sealing these features. The wells (infiltration) that are planned between the shaft and a contaminated site may, if needed, further reduce the effect of the construction on hydraulic head and flow. Changes that are of interest since they may also influence the mobility of a contamination. A low grouting pressure is used in rock adapting to a shallow depth (curtain grouting) and a possible horizontal connectivity. The steps of the observational method, as described by Peck (1969), were found very useful. Its focus on “the general nature, pattern and properties” and “a working hypothesis of behaviour” is of particular interest, highlighting the understanding of the system at hand.
Analysis of failure behaviour of the anisotropic rocks in the point load index test
Authors: Acharya D , Panthee S , Raina A K , Dhakal S 
Published: September 2021

Abstract
The strength and deformational behaviour of rocks under loading conditions are important in underground excavations, mining and every civil engineering constructions as it determines the stability of such structures. This study aims to augment the existing know-how on such behaviour through analysis of point load tests conducted on anisotropic rocks of metamorphic nature. Three types of anisotropic rocks named augen gneiss, granitic gneiss, psammitic schist, and greenschist from different formations of the Lesser and Higher Himalaya of Central Nepal have been investigated. It is observed that the point load index strength of the anisotropic rocks is related to their grain size and the loading angle with respect to the planes of anisotropy. The anisotropic index shows pronounced effects on the surface energy distribution of the samples on the application of stress.
Evaluation of Weathered Rock Mass Strength and Deformation Using Weathering Indices
Authors: Chala Endalu T , Rao KS 
Published: September 2021

Abstract
Rock weathering and the resulting effects on geotechnical properties of weathered rock mass has long been a concern for geotechnical engineering practicing since the strength and deformational properties of weathered rock masses is needed for analysis and design of underground openings, opens pits and excavations for foundations of dams, bridges and high-rise buildings in and on weathered rock mass. It is a very challenging task to obtain required core samples to determine the strength and deformation behavior for the assessment of weathered rock mass performance. This is because of weathering which causes change in fabric of rock by creating voids and micro cracks after dissolving grain boundaries particularly, at higher stage of weathering. This paper attempt to present a method of sampling and testing of weathered rocks and proposed a weathered rock mass indices chart for estimating rock mass strength and deformation properties. To investigate the applicability of the proposed weathered rock mass indices chart for other regions, available data from literature for same rock has been used along with the extensive testing data generated in the present investigation Deccan plateau basaltic rocks.
Study of blasting effect on bench stability
Authors: Djoudi M , Bensehamdi S , Fredj M 
Published: September 2021

Abstract
The study of blast effect on bench stability is indispensable, because the overall stability of the quarry’s slope is directly linked to it. For this purpose, a study is conducted in a limestone quarry. Before the stability analysis, a fragmentation evaluation is carried out by two methods, by the Kuz-Ram model and the Digital Image analysis method using the WipFrag program, this part of the work aims to establish a more efficient blast design that assures a better fragmentation and a higher stability for the quarry’s structure. Afterwards, a numerical stability analysis approach is adopted, by employing the Finite Element Method (FEM) through the Phase2 software. A 2D numerical model of the quarry’s profile is constructed, on which simulations are carried out for two cases: 1-static conditions; 2-Dynamic conditions using the proposed blast design. This analysis goals are to define the possible deformation that the blasting process could engender to the benches and its effect on bench’s stability as an individual case and on the overall stability of the slope in general.
Pre-failure deformation monitoring as rockfall prediction tool
Authors: Marjanović Miloš , Abolmasov Biljana , Berisavljević Zoran , Pejić Marko , Vranić Petko 
Published: September 2021

Abstract
In this article, we are elaborating an example of predictive rockfall assessment by using Terrestrial Laser Scanning (TLS) in monitoring a road cut, hosted in flysch rock formation, near Ljig in Serbia. A sequence of rockfall events from 2013-2019 is presented, while the cut has been more broadly investigated in our earlier work. Beside occasional rockfalls which are routinely detected by annual TLS monitoring, it was possible to track the pre-failure deformations preceding a series of rockfalls, reaching 0.3 m3 in volume with 0.5 annual reoccurrence probability. Monitoring enabled identification of subtle displacements of about 1 cm after the first event in 2014 and keeping track of its progression. After a series of events in the following years, we were able to define the pre-failure threshold which can be applied to the adjacent rock blocks, assuming a similar block volume. It also enabled us to anticipate and simulate the event before it happens. This approach allows planning, prevention and protection, and there is a great deal of interest to standardize it for high-risk slopes and cuts in rock masses.
High-quality timber species production under multi-storey forest management approach in Malaysia
Authors: Jemali N J N , Yahya J , Bam H N R , Majid S , Muhammad M 
Published: September 2021

Abstract
The multi-storey forest management project (MFMP) intended to identify the best silvicultural practices for tropical forest tree species as well as producing high-quality timber and seeds in a multi-storey forest. Plots were established to examine the transition of existing forest plantations and secondary forest to multi-storey forest type. The study aims to evaluate the current performance of the growth rate and productivity of selected local species through a multi-storey forest management approach. Based on the growth performance and productivity obtained, it was found that the method of planting under shading is a practical approach compared to the open planting method. Acacia mangium is planted 3-4 years earlier which acts as shade trees. Five study designs implemented using crop strip at a distance of 3.0 x 3.7m alternating between three different local species and shade trees with a ratio of A (1: 1), B (2: 2), C (4: 4), D (8: 8) and E (16:16). From this study, we found that Malaysia’s local timber species can grow under the shade at the beginning of establishment and it can grow well on narrow crop lines such as crop design A and B. On the other hand, these local species need sufficient levels of sunlight as well as other environmental requirements such as humidity, soil and weather changes over time as they grow. For that reason, these three local species namely Shorea leprosula, Shorea parvifolia and Neobalanocarpus heimii showed good performance in crop design C, D and E. This multi-storey forest management concept can be practised for the establishment of forest plantations and silvicultural treatment in degraded areas with high-quality local timber species.
Species diversity and enumeration of shrub species in Pantai Sabak, Kelantan, Malaysia
Authors: Zamri N A Z , Majid N A Ab , Mohd Zulkafli N N , Ahmad Zu S A , Hamzah Z , Zakaria R , Amaludin N A 
Published: September 2021

Abstract
Coastal forest plays a vital role in our ecosystem because of its numerous and varied human use. In Malaysia especially Kelantan, there is a lot of coastal forests that are not recognised or has been introduced as the forest that consists of much biological diversity that can be important and useful for the development and management of the forest. This study documented shrubs species that were found in Pantai Sabak, Kelantan where all shrubs species were identified and enumerated by using a systematic plot sampling method while relating it with soil composition and their characteristic. A total of 3752 shrubs plants representing 28 species belong to 24 genera from 17 families were identified within 0.05 hectare plots. Species diversity with Shannon-Wiener Diversity Index (H’) with a value of 1.67, while H
max
was 3.34 and Evenness Index (EH) value was 0.50 for the entire study area. Family Capparaceae (1425) and Euphorbiaceae (1260) were dominant families grown in loam and silt soil and the least dominant represented by Vitex rotundifolia and Ipomoea pes-caprae species which grown in sandy soil. Only certain species can grow and be able to survive in different habitats where types of soil play an important role in the factors of the tree species that grow around Pantai Sabak which can be observed that during the study was conducted.
Potential of a combination of Heliconia psittacorum and its associated bacteria for phytoremediation
Authors: Baharuddin M I , Aweng E R , Kutty S R M , Mohd Roslan S N , Hanaphi R M 
Published: September 2021

Abstract
Remediation has recently received a lot of attention to combat or deal with contaminated soil, water, or air. There are a few types of remediation technologies, such as microbiological remediation and phytoremediation, in which microbial remediation uses microorganisms as the agent, while phytoremediation uses flowers as the agent. H.psittacorum is a flower with phytoremediation and ecologically favorable potential. The study is aimed at learning more about the microorganisms that could help improve soil and water quality. Microbiological remediation uses microorganisms as the agent, while phytoremediation uses flowers as the agent to overcome contamination problems. H.psitacorum was found to be able to remove copper, zinc, and phosphorus from soil and groundwater. As a result, H.psittacorum’s phytoremediation capacity was measured in soil and root samples. Microorganism awareness within the root pattern increased to 4.4 × 109 cfu/ml, whereas the soil pattern increased to 1.5 × 109 cm/ml. The concentration and identity of bacteria in roots and soil revealed information about these bacteria’s ability to remove pollutants, while the water quality assessment demonstrated H.psitacorum’s potential. These seven bacteria have been identified as having a historical mechanism that has proven to be effective in removing, transferring, and stabilizing pollutants. In addition, a water quality assessment demonstrated H.psitacorum’s phytoremediation potential reduced copper, zinc, and phosphate concentrations in the water from 0.64 to 0.068 mg/l, and 0.513mg/l to 0. The concentration and identity of bacteria in roots and soil revealed information about these bacteria’s ability to remove pollutants.
Potential of oil palm trunk starch as flocculant for contaminant of emerging compound removal
Authors: Mohd Amin M F , Mat Rasat M S , Ahmad M I , Aftar Ali N S , Muda K , Zaidi N S , Ismail S , Mohamad Shahimin M F , Mohd Amin M A , Salam M A 
Published: September 2021

Abstract
In this preliminary study, a natural flocculant is developed from an oil palm trunk. The flocculant further tested for its ability in turbidity and COD removal with additional of atrazine in wastewater and demineralised water matrix. At the optimum dosage of 20mg/L, the developed cationic OPT starch able to remove around 95% turbidity and 85% COD. In addition, the cationic OPT starch also show the ability to remove spiked atrazine from both water matrixes to the maximum range of 55-85%. In conclusion, the developed oil-palm based flocculant show great potential for real-world application with added cost-effective benefits.