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The purpose of this study is to investigate the deformation characteristics and failure modes of the right bank slope of Xiluodu Hydropower Station after excavation.

Micro-seismic monitoring technology is applied to obtain the microfracture information and study the internal damage evolution law of the slope rock mass. A numerical model for discontinuous deformation analysis (DDA) is established to analyse the deformation characteristics and failure mode of the slope. Micro-seismic monitoring and DDA can verify and supplement each other's results in the investigation of slope failure.

The results show that the slope has a downhill displacement along the weathered zone under natural conditions; the maximum resultant displacement at the monitoring point is 380 mm. The micro-seismic events are concentrated in an area located 30–100 m horizontally away from the slope surface and at an elevation of 390–470 m. The distribution of these micro-seismic events is consistent with the location of the unloading and weathered zones; it is the same as the DDA simulation result.

The study is anticipated to be used as reference for the stability analysis of rock slopes. By combining the continuous (micro-seismic monitoring technology) and discontinuous (DDA) methods, the entire process starting from the gradual accumulation of internal rock micro-damage to the macroscopic discontinuous deformation and failure of the slope can be investigated.

Total organic carbon (TOC), dissolved organic carbon (DOC) and other physicochemical parameters of the Birim River, which serves for drinking and domestic purposes for rural mining communities, were analysed to assess the suitability of water quality for human consumption.

In total, 40 samples were collected from 20 sampling sites during the rainy season from July to September and the dry season from December to February in addition to two repeat samples and two blank samples. Samples were analysed for physiochemical parameters and the results were compared with World Health Organisation standards (WHO).

Data obtained for both rainy and dry seasons indicated TOC ranged from 1.1 to 7.3 mg/L and DOC 1–7.2 mg/L; pH, 5.6–8.63; temperature, 23.3–29.3°C; turbidity, <1.00–869NTU; apparent colour, <2.5–600 mg/L Pt-Co; true colour <2.5–150 mg/L Pt-Co; alkalinity, 27.8–80.4 mg/L; total suspended solids, <1.00–998 mg/L; electrical conductivity, 82–184 µS/cm; and bicarbonate, 33.9–98.1 mg/L. Particulate organic carbon (POC) was constituted between 1 and 10% of the TOC. Values for pH, turbidity, total suspended solids, and true colour indicated contamination of the river. p -value of <0.05 between seasons for the physicochemical parameters also suggests that the water is polluted.

Water from the Birim River is unsuitable for human consumption and may constitute a serious health risk to the consumers.

The paper yields immense value to inhabitant of communities using surface water affected by mining activities, policy makers in sustainability. It warns of the unsuitability of water from the Birim River for human consumption due to the potential health risk to consumers.

This paper aims to present a case study of some current disorders affecting the stone‐panels of façade claddings, i.e. cracking, spalling close to anchorage systems and staining. The purpose of this study is to identify the origin of the mechanical and chemical disorders of the carbonate rock thin panels of the “Les Chênes 1” building of the University of Cergy‐Pontoise (France).

Mapping of the disorders, anchorage system investigation at spallings, chemical analyses of oil‐like stains were performed in order to characterize both disorders. Porosity and capillarity properties of the rock were measured and compared between samples collected outside and within a stain.

Mechanical disorders result from vandalism or poor implementation. Spallings are disorders very likely in evolution. Their occurrence may increase through time. Stains are made of silicone destabilization products.

A model is proposed for the formation of oil‐like stains. Water is required to destabilize silicone sealant and to drive the migration of the degradation products through the porous media and towards the surface of the plate exposed to rainfall.

The purpose of this study is to evaluate how accurately a 3D printer could manufacture basic porous models. Geoscience research is evolving toward numerical prediction of porous rock properties, but laboratory tests are still considered a standard practice. 3D printing digital designs of porous models (proxies) is a way to bridge the gap between these two realms of inquiry.

Digital designs of simple porous models have been 3D-printed on an inkjet-style (polyjet) 3D printer. Porosity and pore-throat size distribution of proxies have been measured with helium porosimetry, mercury porosimetry and computed tomography (CT) image analysis. Laboratory results on proxies have been compared with properties calculated on digital designs and CT images.

Bulk volume of proxies was by 0.6-6.7 per cent lower than digital designs. 3D-printed porosity increased from 0.2 to 1.9 per cent compared to digital designs (0-1.3 per cent). 3D-printed pore throats were thinner than designed by 10-31 per cent.

Incomplete removal of support material from pores yielded inaccurate property measurements. The external envelope of proxies has been 3D-printed at higher accuracy than pores.

Characterization of these simple models improves understanding of how more complex rock models can be 3D-printed accurately and how both destructive (mercury porosimetry) and non-destructive (CT and helium porosimetry) methods can be used to characterize porous models.

Validation of 3D-printed porous models using a suite of destructive and non-destructive methods is novel.

Dolomite is of immense importance for industrial applications. It is occuring in many locations in Egypt. Complete investigation and identification of the ore has been performed via chemical analysis and spectro‐photometric measurements using X‐ray fluroscence, X‐ray diffraction and electron microscope. The X‐ray diffraction pattern indicated that Egyptian dolomite is a crystalline material and electron microscope analysis showed that it has a lameller shape. Egyptian dolomite sample was evaluated as an extender pigment according to standard international specifications and proved to be excellent one for coating applications. Surface modification of dolomite ore particles has been carried out using stearic acid in cyclohexane. The modification concerned with the determination of adsorption isotherm, sediment volume, sedimentation rate, and dispersion properties to determine monolayer surface coverage of the ore particles. The unmodified and modified dolomite samples have been incorporated in anticorrosive primer formulations. The painted films were tested and examined in the laboratory accelerated corrosion test. Promising results were achieved and the films showed high performance as efficient extender pigment for coating applications that can replace satisfactorily its similar imported pigments.

This is an initial attempt to classify natural roofing slate quality using the new European Standard BS EN 12326 and suggest how such classification may be employed to predict in‐service performance and identify potentially problematic materials.

A wide range of natural roofing slates has been subjected to the new standard testing regime and additional tests carried out. Experience of known in‐service performance and previous test results have also been taken into consideration.

An initial classification of natural roofing slate quality has been proposed with the flexural strength, water absorption, potential for oxidation and carbonate content considered to be the key components.

There is considerable scope for refinement of the proposed classification by investigating the performance of the wide range of other natural roofing slates available and taking the results into consideration. Predicted in‐service performance is based on practical experience and can be considered only a general guide.

By classifying natural roofing slate quality users will be able to make better informed purchasing decisions based on cost versus quality. Slate producers, especially those with higher quality slates, will also be able to market their materials accordingly with less chance of losing out to lower quality, potentially problematic materials that still conform to the new standard.

The concept of a quality classification for natural roofing slate is not new, but this has been omitted during the creation of the new standard. The proposed classification is broader and probably better defined than those in existence elsewhere or previously used within the European Union member states.

Deals with a study of the mineralogical and organic components of the monthly dust‐fall deposited over Al Ain city, some 150km east of Abu Dhabi and 130km south‐east of Dubai. The identification of the mineralogical and organic composition was carried out by means of infra‐red spectroscopy. This study reveals that the principal constituents of dustfall, over the studied city are calcite, gypsum, kaolinite, quartz, hematite, alkanes and phosphines. The sources of these constituents are attributed to local controls, both natural and man‐induced

Evaluating mechanical properties of simply made samples by 3D printing technology at nanoscale provides a clear path to better understand larger-scale responses of complex natural rocks. Therefore, to realize the similarity between synthetically manufactured materials and natural geomaterials, this study focused on nanoscale mechanical characterization of a 3D printed object with only two constituent components (gypsum powder and infiltrant).

The study method includes nanoindentation technique combined with numerical simulation via discrete element method (DEM).

Four typical load-displacement curves were identified from nanoindentation of total test points indicating a typical elastic-plastic behavior of the 3D printed gypsum rock sample. Mechanical parameters such as Young’s modulus and hardness were calculated by energy-based methods and a positive correlation was observed. The infiltrant was found to considerably be responsible for the majority of the sample nano-mechanical behavior rather than the gypsum particles, thus expected to control macroscale properties. This was decided from deconvolution and clustering of elastic modulus data. Particle flow modeling in DEM was used to simulate the nanoindentation process in a porous media yielding rock-alike mechanical behavior.

The results show a matching load-displacement response between experimental and simulation results, which verified the credibility of simulation modeling for mechanical behavior of 3D printed gypsum rock at nanoscale. Finally, differential effective medium theory was used to upscale the nanoindentation results to the macroscale mechanical properties, which provided an insight into the geomechanical modeling at multiscale.

The purpose of this paper is to show that Uttaranchal is a hilly State, recently constituted in the Himalayan region. Over 80 percent of Uttaranchal state is prone to slope instability because of weak and highly folded and fractured rocks, steep slopes, high seismicity and unfavorable hydro‐geological conditions. In addition to this, unsystematic development construction activities contribute to the problem. Newly formed Uttaranchal state is in the process of development, required to expand the existing infrastructure.

The paper gives a full description: Bending of rock beds, their disjointing, disruption and drag‐folding are characteristic features of a creeping mass. Tilted trees and poles are indicative of creep movement as seen on a number of hillslopes in and around Nainital town. The curvature of the tree trunks bears record to the rate of creep during the period of growth of the tree. It hardly needs stating that the rate of creep movement is quicker during the rainy season, and there may be long periods stretching over years when no movement at all takes place. The temporal span of this phenomenon stretches over thousands of years. The rate is accelerated by clear‐felling in forests and by construction on steeper slopes. The depth of the creep movement is variable, and depends largely on the nature and degree of weathering of rocks, the sub‐surface structure and amount of water present within.

It was found that, to meet the requirement, construction activities are in full pace, which have given rise to the new landslide problems or have aggravated the existing slope instability problems. In order to keep the landslide problems to a minimum, systematic studies are required on every aspect of the slope instability problems.

On the basis of slope instability evidence, past occurrence of landslides, deformation of civil structures and geological conditions, three zones have been identified – safe, moderately safe, and very unsafe.

The paper describes the natural problems with which Uttaranchal is faced and proposes systematic studies which are required to deal with every aspect of the outstanding problems of slope instability.

According to the results of FMI log interpretation and the water cut trend of low permeable carbonate reservoirs, the model of the fluid distribution in the fracture-cavity pore was derived. Based on the material balance principle, assuming the original water contribution to production as constant water influx, a new calculating method for the low permeable carbonate reservoir geological reserves was presented. This method estimated the impact of origin aquifer to the geological reserves. The calculating results of example indicate that comparing to numerical simulation, this new method is high accuracy and easy to use.