Deriving preference order of post-mining land-uses through MLSA framework: application of an outranking technique

This study intends to take advantage of a previously developed framework for mined land suitability analysis (MLSA) consisted of economical, social, technical and mine site factors to achieve a partial and also a complete pre-order of feasible post-mining land-uses. Analysis by an outranking multi-attribute decision-making (MADM) technique, called PROMETHEE (preference ranking organization method for enrichment evaluation), was taken into consideration because of its clear advantages on the field of MLSA as compared with MADM ranking techniques. Application of the proposed approach on a mined land can be completed through some successive steps. First, performance of the MLSA attributes is scored locally by each individual decision maker (DM). Then the assigned performance scores are normalized and the deviation amplitudes of non-dominated alternatives are calculated. Weights of the attributes are calculated by another MADM technique namely, analytical hierarchy process (AHP) in a separate procedure. Using the Gaussian preference function beside the weights, the preference indexes of the land-use alternatives are obtained. Calculation of the outgoing and entering flows of the alternatives and one by one comparison of these values will lead to partial pre-order of them and calculation of the net flows, will lead to a ranked preference for each land-use. At the final step, utilizing the PROMETHEE group decision support system which incorporates judgments of all the DMs, a consensual ranking can be derived. In this paper, preference order of post-mining land-uses for a hypothetical mined land has been derived according to judgments of one DM to reveal applicability of the proposed approach.     

Early Cretaceous <Emphasis Type="Italic">Neotrocholina</Emphasis> Reichel, 1956 from the Tirgan Formation,Kopet Dagh sedimentary basin,NE Iran: systematic and biometric interpretation

Neotrocholina Reichel, 1956 is one of the most important benthic foraminifera in Early Cretaceous. Some of the species of this genus are indexes in biostratigraphy especially for this interval (e.g., Neotrocholina friburgensis: Late Barremian–Early Aptian; Neotrocholina aptiensis: Early Aptian). In order to conduct accurate paleontological investigations, sampling from the carbonate units of the Tirgan Formation in Kopet Dagh sedimentary basin is done. According to the occurrence level in the studied stratigraphic sections as well as biometric interpretations, two species of this genus (N. friburgensis and Neotrocholina valdensis) are pointed out.     

THREE-DIMENSIONAL GEO-MORPHOLOGICAL MODELLING OF ESTUARINE WATERS

1 INTRODUCTION Estuaries and coastal zones have been used as means of navigation, disposal of waste material, fishing and many commercial and economic activities over the centuries. One of the most important phenomena in these regions is the suspended sediment transport, which may cause erosion and deposition, and hence changes in the estuarys morphology. In turn, such changes may lead to problems relating to navigation and estuarine management. When the bed boundary of an estuary change…     

Stiffness identification of two- and three-dimensional frames

Four widely used structural system identification methods are presented. Based on Bayesian estimation theory, two new formulae and their derivations are shown. Time domain responses of two frames when subjected to the ground motion of the El Centro earthquake are computed then transformed to the frequency domain. Frequencies and mode shapes of frames are extracted from Fourier spectra. Using these frequencies and mode shapes, a parametric study is conducted, and the system identification methods are compared and discussed. The importance of a prior analytical model on the rate of convergence of the revised parameters is investigated. Recommendations are given regarding the feasibility of each method for more accurate estimation. A model suitable for parameter identification of three-dimensional frames is presented. This model, with different identification methods, is used to estimate the parameters of a two-storey frame.     

An elastoplastic description of frictional destructuration in natural clays and shales

The existence of structuration in natural clays and shales is believed to change their stiffness, yielding, dilatancy and strength characteristics. These constitutive features are widely known to ultimately reunite with those of the reconstituted parent soil upon large straining. However, some experimental results show that such reunification may not occur in isotropic/one-dimensional compression, especially with regard to the critical state friction angle. This peculiar phenomenon has been barely addressed in constitutive models for natural geomaterials. Hence, the present study aims at introducing a structure-dependent critical state friction angle within the subloading yield framework. A new internal variable is introduced in the model of Nakai et al. (Soils Found 51(6):1149–1168, 2011) to capture subtle irreversible degradation of the structured critical state line which also serves as the threshold between contractive and dilatant volume changes. Additionally, a new evolution rule for the proposed destructuration factor is developed by considering important microstructural information revealed by discrete element method simulations. The proposed new modifications not only enhance the model capabilities in predicting bonding effects, but also enrich the classical stress-dilatancy equation by rendering it a function of void ratio, mean stress and the microstructural state. Model simulations of laboratory experimental tests on the Colorado shale as well as Bacinetto clay are presented in order to illustrate the improved predictive capabilities of the new model.     

Design and full‐scale experimental evaluation of a seismically endurant steel buckling‐restrained brace system

This paper presents the results of 12 full‐scale tests on buckling‐restrained brace (BRB) specimens. A simple‐to‐fabricate all‐steel encasing joined by high‐strength bolts was used as the buckling‐restrainer mechanism. Steel BRBs offer significant energy dissipation capability through nondeteriorating inelastic response of an internal ductile core. However, seismic performance of BRBs is characterized by interaction between several factors. In this experimental study, the effects of core‐restrainer interfacial condition, gap size, loading history, bolt spacing, and restraining capacity are evaluated. A simple hinge detail is introduced at the brace ends to reduce the flexural demand on the framing components. Tested specimens with bare steel contact surfaces exhibited satisfactory performance under the American Institute of Steel Construction qualification test protocol. The BRBs with friction‐control self‐adhesive polymer liners and a graphite‐based dry lubricant displayed larger cumulative inelastic ductility under large‐amplitude cyclic loading, exceeding current code minimum requirements. The BRB system is also examined under repeated fast‐rate seismic deformation history. This system showed significant ductility capacity and remarkable endurance under dynamic loading. Furthermore, performance is qualified under long‐duration loading history from subduction zone's megathrust type of earthquake. Predictable and stable performance of the proposed hinge detail was confirmed by the test results. Internally imposed normal thrust on the restrainer is measured using series of instrumented bolts. Weak‐ and strong‐axis buckling responses of the core are examined. Higher post‐yield stiffness was achieved when the latter governed, which could be advantageous to the overall seismic response of braced frames incorporating BRBs.     

A review of flood damage analysis for a building structure and contents

Natural Hazards - As a natural hazard, flood can cause a significant damage to buildings. Buildings are one of the important components of an economy which are providing the necessary space for...     

Dynamic response of double beam rested on stochastic foundation under harmonic moving load

This paper deals with the dynamic response of infinite double Euler–Bernoulli beam supported by elastic foundation with stochastic stiffness subjected to an oscillating moving load, which is the first research in relevant literature review. In this matter, equations of motion for double beam are formulated in a moving frame of reference. Moreover, by employing the first order perturbation theory and calculating contour integration, the response of double beam is obtained analytically and validated by a stochastic finite element model. Sensitivity analyses on the various parameters of closed form solution such as velocity, load frequency, coefficient of variation of soil foundation and rail and slab bending stiffness show the significant effect of load frequency on the dynamic response of the doubled beam. From practical point of view, the obtained results of the present study can be utilized efficiently in analysis and design of slab track systems. Copyright © 2013 John Wiley & Sons, Ltd.     

Rocking vibration of a rigid circular disc in a transversely isotropic full‐space

In this paper, forced rocking vibration of a rigid circular disc placed in a transversely isotropic full‐space, where the axis of material symmetry of the full‐space is normal to the surface of the plate, is analytically investigated. Because of using the Fourier series and Hankel integral transforms, the mixed boundary‐value problem is transformed into two separate pairs of integral equations called dual integral equations. The dual integral equations involved in this paper are reduced to Fredholm integral equations of the second kind. With the aid of contour integration, the governing integral equation is numerically evaluated in the general dynamic case. The reduced static case of the dual integral equations is solved analytically and the vertical displacement, the contact pressure and the static impedance/compliance function are explicitly determined, and it is shown that the pressure in between the plate and the full‐space and the compliance function reduced for isotropic half‐space are identical to the previously published solutions. The dynamic contact pressure in between the disc and the space and also the related impedance function are numerically evaluated in general dynamic case and illustrated. It is shown that the singularity exists in the contact pressure at the edge of the disc is the same as the static case. To show the effect of material anisotropy, the numerical evaluations are given for some different transversely isotropic materials and compared. Copyright © 2010 John Wiley & Sons, Ltd.