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The purpose of this paper is to investigate the anisotropic characteristics of the special structure of a columnar jointed rock masses and provide reference to forecast the behavioral characteristics of real samples.

This study used FLAC3D numerical software to simulate the mechanical behavior of columnar jointed rock masses with different columns angles (ß) under different stress conditions. The peak strength, elastic modulus and Poisson’s ratio were obtained to investigate the strength, deformation characteristics and failure modes of the rock masses under conventional and true triaxial compression.

The results showed that the compressive strength of the specimens presents a U-shape under different joint inclinations. The strength of the specimens reaches a maximum value when ß = 90°, and the value for ß = 0° is slightly lower and reaches a minimum value when ß = 50°. The elastic modulus and Poisson’s ratio of the samples are obviously anisotropic, the anisotropic coefficient decreases with increasing confining pressure. When σ₂ ≠ σ₃, the peak strengths of the samples are related to the direction of the minor principal stress, and the failure modes of the samples are related to the confining pressure and joint inclination.

The present paper uses a numerical simulation method to examine the strength and deformation characteristics of a columnar jointed rock mass under conventional and true triaxial compression. The aim is to provide a reference to forecast the mechanical characteristics of test samples in the laboratory.

Cemented conglomerate accumulation is a weak and heterogeneous medium that occurs in western China. It consists mainly of argillaceous cement that loses strength rapidly upon contact with water, leading to collapse instability failure. Its deformation failure mechanism is complex and poorly understood. In this paper, the erosion failure mechanism of cemented conglomerate accumulation is investigated.

The collapse failure process after erosion of the slope foot for typical cemented conglomerate accumulation is studied based on field investigation using the particle discrete element method. And how the medium composition, slope angle and cementation degree influence the failure mode and process of the cemented conglomerate accumulation is examined.

The foot erosion of slope induces a tensile failure that typically manifests as “erosion at the foot of slope – tensile cracking at the back edge of slope top – integral collapse.” The collapse failure is more likely to occur when the cemented conglomerate accumulation has a higher rock content, a steeper slope angle or a weaker cementation degree.

A model based on rigid blocks and disk particles to simulate the cemented conglomerate accumulation is developed. It shows that the hydraulic erosion at the foot of the slope resulted in a different failure mechanism than that of general slopes. The results can inform the stability management, disaster prevention and mitigation of similar slopes.

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 development of models that allows the evaluation and prediction of erosion processes is an important tool for the management and planning of coastal systems. Mangrove forests systems are under threat by the impacts of erosion, which is also intensified by human activity (and aggravated in the scenarios of global warming and climate change). The purpose of this paper is to develop a model of geographic information systems (GIS) that can be used for any estuary area, but it can also be used for mangroves.

This paper uses georeferentiation which is defined as a set of parameters that best characterize the mangrove areas: elevation (m); geomorphology; geology; land cover; anthropogenic activities; distance to the coastline (m) and maximum tidal range (m). Three different methods are used to combine the various vulnerability parameters, namely, DRASTIC index, analytical hierarchy process (AHP) and square root of the geometric mean.

The three approaches presented in this work show different types evaluating vulnerability to erosion, highlighting a stronger overvaluation of the areas presented with a high vulnerability, through the use of DRASTIC index when compared with two other approaches. The use of the AHP shows similarity to the square root of the geometric mean model, but the AHP also presents a higher percentage of vulnerable areas classified as having medium to very high vulnerability. On the other hand, the use of square root of the geometric mean led to a higher percentage of areas classified as having low and very low vulnerability.

These three qualitative models, based on a cognitive approach, using the set of parameters defined in this research, are a good tool for the spatial distribution of erosion in different mangroves in the world.

Global warming and climate change scenarios require adaptation and mitigation options supported by science-based strategies and solutions.

Although there have been extensive studies on the hydrological and erosional impacts of logging, relatively little is known about the impacts of conversion into agricultural plantation (namely rubber and oil palm). Furthermore, studies on morphological impacts, sediment-bound chemistry and forensic attribution of deposited sediment to their respective sources are scarcer. This chapter introduces the potential for using the multi-proxy sediment fingerprinting technique in this context. Featuring pilot projects in two major flood-prone river systems in Malaysia, the studies explore application of geochemistry-based sediment source ascription. The geochemical signatures of sediment mixtures on floodplains were compared to sediments from upstream source tributaries. The tributaries were hypothesised to have different geochemical signatures in response to dominant land management. The first case study took place in the Segama River system (4,023 km²) of Sabah, Malaysian Borneo where a mixture of primary forest, logged-forests and oil palm plantations were predominant. The second case study was in the Kelantan River Basin (13,100 km²) with two major tributaries (Galas River and Lebir River) where logged-forests and rubber and oil palm plantations are dominant land-uses. Both case studies demonstrated the applicability of this method in ascribing floodplain deposited sediment to their respective upstream sources. Preliminary results showed that trace elements associated with fertilisers (e.g. copper and vanadium) contribute to agricultural catchment signatures. Alkaline and alkaline-earth elements were linked to recently established oil palm plantations due to soil turnover. Mixing model outputs showed that contributions from smaller, more severely disturbed catchment are higher than those from larger but milder disturbed catchments. This method capitalises on flood events to counter its adverse impacts by identifying high-priority sediment source areas for efficient and effective management.

In this chapter, the authors provide an introspective account of how teachers in mainstream classrooms can use questioning to more effectively differentiate literacy instruction for English learners across subject areas. The authors offer a rationale for constructively responsive questioning and share tools and strategies for adapting levels of questioning to students’ English proficiency and grade levels with the goal of strengthening instruction and promoting student engagement in learning.

This paper aims to formulate and prepare a series of alkyd paints with new anticorrosive pigments, eco-friendly to the environment, based on a natural zeolitic rock modified by ion exchange to incorporate passivating cations.

The electrochemical characterization of the painted steel was carried out by conductivity measurements, linear polarization tests, measurements of the corrosion potential and electrochemical noise measurements. Besides, accelerated tests in standard environmental chambers were also carried out.

The results show that clinoptilolite–mordenite-based pigments incorporated in the paint provide acceptable anticorrosive properties, taking into account their low environmental impact and the use of a natural resource of low cost. The inhibitory efficiency of ZLa is higher than 80% and of ZPr is close to 70%. The electrochemical assays of the coated panels with the alkyd paints ZLa and ZPr shows similar behavior.

In this work, good results were obtained with an alkyd resin, but other resins could be tested. Paints could also be formulated with modified zeolites as a complement to others traditional anticorrosive pigments.

These paints could be used for the protection of metal structures in low corrosive environments.

There are not many published works using zeolites as anticorrosive pigments.

Purpose – Flooding has become a recurring phenomenal in most cities in Nigeria. The 26 August 2011 flooding disaster which occurred in Ibadan is only an indication of magnitude of flooding problem in Nigerian cities. This chapter examines the impacts, vulnerability factors and disaster risk management framework in Ibadan metropolis.

Methodology/Approach – The survey design was used for the study and covers eleven local government areas (LGAs) affected by the flood. The study utilized both primary and secondary data. The primary data were obtained by physical observation and in-depth interview of affected households. In-depth interview was also carried out with key officials of State Ministry of Environment and Housing. The study also relies on the data from the Oyo State Government Task Force on Flood Prevention and Management report.

Findings – The chapter shows that the 26 August 2011 flood disaster in Ibadan metropolis caused monumental destructions in the city. The continuous construction on flood plains, indiscriminate dumping of refuse, excessive rainfall and deforestation were identified as the main vulnerability factors. The chapter shows that there is no adequate framework for disaster risk management in the city.

Research limitations – About 250 affected households in 11 LGAs were interviewed for the study due to time and budget constraints. This figure is considered meagre considering the number of affected households by the flood disaster. However, the random selection of affected households and key government officials helped to address this limitation.

Originality/value of chapter – The simultaneous identification of impacts, vulnerability factors and disaster risk management framework in the city provides an opportunity for the development of a holistic and proactive disaster risk management strategy in Ibadan metropolis.

The purpose of this paper is to give a better knowledge of water resources in the region of Ben Azzouz, and to improve the actual water management through harmonization between the various human communities needs.

After an overview of the geology and hydroclimatology of the study area, the work will be to identify the factors involved in the water balance in the quantitative assessment of groundwater resources, to define areas of use and to estimate water needs for different uses.

The study of the area shows two distinct water reservoirs: the deep aquifer composed of fractured limestone, sands and gravels, and surface massive dune sand aquifer. The impermeable formations are the metamorphic basement and overlying flyschs nappes. Because the average rainfall is relatively high (∼708 mm/year), the region is known by its agricultural vocation and, therefore, most of surface water is assigned to irrigation. The second potential water consumer is population with 2.660 Hm3/year, then industrial needs are 1.793 Hm3/year. Although there was no marked water deficit in the region in the period 2007-2013, it is now time to apply concepts of integrated and sustainable management of water resources in this region because of the growing agricultural practice and population needs.

A quantitative diagnosis of water potential of the study area was evaluated for a better rational use of water resources.