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Prediction of Restraint Moments in Precast, Prestressed Structures Made Continuous

REFERENCES 1. Finnish Concrete Society: “Concrete Textbook 2018, by201,” Vaasa, Finland, 2018, 568 pp. (In Finnish). 2. International Federation for Structural Concrete (fib): “CEB-FIP, Model Code 2010,” Final draft, Volume 1, Bulletin 65, Switzerland, 2012, 357 pp. 3. American Association of State Highway and Transportation Officials: “AASHTO LRFD Bridge Design Specifications, Customary U.S. Units,” Section 5, “Concrete Structures,” Washington DC, USA, 2012, 332-589 pp. 4. Miller R A, Castrodale R, Mirmiran A & Hastak M: “NCHRP Report

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Wear Resistance of the Cermet Cutting Tools After Aluminum (Al+) and Nitrogen (N+) Ion Implantation

.A., Matula G.: Podstawy metalurgii proszków i materiały spiekane. Cermetale narzędziowe. Open Access Library 8 (2012) 9-39. 6. Shepard S.R., Suh N.P.: The Effects of Ion Implantation on Friction and Wear of Metals. Journal of Lubrication Technology, 104 (1982) 29-38. 7. Huang X., Etsion I., Shao T., Effects of elastic modulus mismatch between coating and substrate on the friction and wear properties of TiN and TiAlN coating systems. Wear, 338-339 (2015) 54-61. 8. PalDey S., Deevi S.C., Single layer and multilayer wear resistant coatings of (Ti, Al)N: A

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Selected aspects of designing deep excavations

Abstract

This paper analyzes two approaches to serviceability limit state (SLS) verification for the deep excavation boundary value problem. The verification is carried out by means of the finite element (FE) method with the aid of the commercial program ZSoil v2014. In numerical simulations, deep excavation in non-cohesive soil is supported with a diaphragm wall. In the first approach, the diaphragm wall is modeled with the Hookean material assuming reduced average stiffness and possible concrete cracking. The second approach is divided into two stages. In the first stage, the wall is modeled by defining its stiffness with the highest nominal Young’s modulus. The modulus makes it possible to find design bending moments which are used to compute the minimal design cross-section reinforcement for the retaining structure. The computed reinforcement is then used in a non-linear structural analysis which is viewed as the “actual” SLS verification.

In the second part, the paper examines the same boundary value problem assuming that the excavation takes place in quasi-impermeable cohesive soils, which are modeled with the Hardening Soil model. This example demonstrates the consequences of applying the steady-state type analysis for an intrinsically time-dependent problem. The results of this analysis are compared to the results from the consolidation-type analysis, which are considered as a reference. For both analysis types, the two-phase formulation for partially- saturated medium, after Aubry and Ozanam, is used to describe the interaction between the soil skeleton and pore water pressure.

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Interpretation of shear modulus degradation tests

1 Introduction One of the key parameters essential for conducting numerical analyses of the geotechnical structure or to conduct its design calculations is the deformation modulus of the separated soil layer. The basis for determining the magnitude of the deformation modulus is the stress–strain relation obtained by an empirical study of the appropriately prepared soil sample. Traditionally, the test enabling the determination of the relationship between the states of stress and strain is the triaxial compression test conducted on cylindrical test specimens

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Torsional Shear Device for Testing the Dynamic Properties of Recycled Material

Committee for Standardization (2013). Geotechnical investigation and testing - Identification and classification of soil - Part 2: Principles for a classification PN-EN 14688-2. [13] SAS W., GABRYŚ K., SZYMAŃSKI A., Effect of Time on Dynamic Shear Modulus of Selected Cohesive Soil on One Section of Express Way No. S2 in Warsaw, Acta Geophysica, 2015, 63(2), 398-413, DOI: 10.2478/s11600-014-0256-z. [14] SAS W., SOBÓL E., GABRYŚ K., MARKOWSKA-LECH K., Study of the cohesive soil stiffness in a modified resonant column, [in:] Materiały

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Use of functional cluster analysis of CPTU data for assessment of a subsoil rigidity

accordance with the assumptions presented in Section 3 . In view of the assumed foundation depth for wind farms and the depth of the shallowest CPTU, the analysis was conducted in the depth range from 2 m to 8 m. Due to the varied thickness of the surface, which was a weak layer, apart from the investigation of the entire profile, analyses were additionally conducted separately in two depth ranges: 2–5 m and 5–8 m below the surface. In accordance with the principles of functional data analysis, the first step included smoothing of the function of the modulus depending on

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First principle calculation of structural, electronic and elastic properties of rare earth nitride

the present study we have used density functional theory with the generalized gradient approximation within the treatment of 4f-states. We have used plane wave pseudo potential density functional theory as implemented in the quantum espresso code [ 11 ]. The ground state properties of B1-type CeN have been studied using this approach. The lattice constant and bulk modulus of this rare earth nitride have also been reported. We further report the electronic band structure (BS) and density of states (DOS) for CeN. The organization of this article is as follows: in

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The concept of modification and analysis of the strength of steel roadway supports for coal mines in the Soma Basin in Turkey

, main central moment of inertia of the cross-section; W , elastic section modulus; W pl , plastic section modulus; σ dop25G2 , allowable stresses for S25G2 steel section; σ dopS480W , allowable stresses for S480W steel sections; σ dopS550W , allowable stresses for S550W steel sections. Computer programs operating based on the FEM algorithm, in addition to displacements and internal forces, automatically calculate the stresses reduced according to the Huber–Mises–Hencky hypothesis according to the general dependence: σ r e d = σ x 2 + σ y 2 + σ z 2 − σ x σ y

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Electronic and structural properties of rare earth pnictides

studied by first principle tight binding linear muffin tin orbital (TB-LMTO) method within the local density approximation (LDA). In the present study it has been found that these solids crystallize in NaCl-type structure. They undergo a first order phase transition from NaCl-type to CsCl-type structure in the pressure range of 11.8 to 14.7 GPa. The electronic band structure (BS) and density of states (DOS) of these pnictides are also reported. The rest of the paper is organized as follows: Section 2 describes the method of calculation of electronic band structure (BS

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Analysis and settlement evaluation of an end-bearing granular pile with non-linear deformation modulus

behaviour. The non-homogeneity of a granular pile is considered in terms of its deformation modulus with non-linear variation. The essential steps of the analysis are described in the following sections. 2.1 Soil displacements The granular pile is discretised into n cylindrical elements acted upon by shear stresses τ, with the base having a uniform pressure p b . The granular pile base is assumed to be smooth, across which the load is uniformly distributed. The soil displacements of the nodes on the granular pile periphery and the centre of each element

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