THE LINEARLIZED PREDICTION OF THE HEAT LOAD IN UNDERGROUND STRUCTURES UNDER THE OPTIONAL TIME FLUCTUATION OF METEOROLOGICAL CONDITIONS

The study of the transport and capture of particles moving in a fluid flow in a porous medium is an important problem of underground hydromechanics, which occurs when strengthening loose soil and creating watertight partitions for building tunnels and underground structures. A one-dimensional mathematical model of long-term deep filtration of a monodisperse suspension in a homogeneous porous medium with a dimensional particle retention mechanism is considered. It is assumed that the particles freely pass through large pores and get stuck at the inlet of small pores whose diameter is smaller than the particle size. The model takes into account the change in the permeability of the porous medium and the permissible flow through the pores with increasing concentration of retained particles. A new spatial variable obtained by a special coordinate transformation in model equations is small at any time at each point of the porous medium. A global asymptotic solution of the model equations is constructed by the method of series expansion in a small parameter. The asymptotics found is everywhere close to a numerical solution. Global asymptotic solution can be used to solve the inverse filtering problem and when planning laboratory experiments.

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ESTIMATION PROCEDURE FOR THE EFFECT OF TRIGGERING FACTORS ON TECHNICAL CONDITION OF LONG-TERM OPERATED UNDERGROUND STRUCTURES IN ROCK MASS

Физико-технические проблемы разработки полезных ископаемых ◽

10.15372/ftprpi20180501 ◽

2018 ◽

Keyword(s):

Rock Mass ◽

Estimation Procedure ◽

Technical Condition ◽

Underground Structures ◽

Triggering Factors

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Increased Heat Load Effects on the Thermal Performance of Single- and Two-Layered Microchannels with Varying Axial Length and Micro Pin-Fin Inserts

International Journal of Fluid Mechanics Research ◽

10.1615/interjfluidmechres.v43.i5-6.60 ◽

2016 ◽

Vol 43 (5-6) ◽

pp. 441-455

Author(s):

Tunde Bello-Ochende ◽

Olayinka O. Adewumi ◽

Josua Petrus Meyer

Keyword(s):

Thermal Performance ◽

Axial Length ◽

Heat Load ◽

Pin Fin ◽

Load Effects

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Determining The Minimum Distance Between Centers of Two Parallel Tunnels to Apply The Law of Super Position in Order to Calculate Subsidence by Using The Software FLAC 3D

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v1i1.2139 ◽

2015 ◽

Vol 1 (1) ◽

pp. 13-20

Author(s):

Hamid Reza Samadi ◽

Mohammad Reza Samadi

Keyword(s):

Minimum Distance ◽

Surface Subsidence ◽

Urban Traffic ◽

Underground Structures ◽

Rapid Population Growth ◽

The North ◽

Flac 3D ◽

The Law ◽

3D Software ◽

Twin Tunnels

Due to the development of cities as well as rapid population growth, urban traffic is increasing nowadays. Hence, to improve traffic flow, underground structures such as metro, especially in metropolises, are inevitable. This paper is a research on the twin tunnels Of Isfahan's metro between Shariaty station and Azadi station from the North towards the South. In this study, simultaneous drilling of subway's twin tunnels is simulated by means of Finite Difference Method (FDM) and FLAC 3D software. Moreover, the lowest distance between two tunnels is determined in a way that the Law of Super Position could be utilized to manually calculate the amount of surface subsidence, resulted by drilling two tunnels, by employing the results of the analysis of single tunnels without using simultaneous examination and simulation. In this paper, this distance is called "effective distance". For this purpose, first, the optimum dimensions of the model is chosen and then, five models with optimum dimensions will be analyzed separately, each of which in three steps. The results of analyses shows that the proportions (L/D) greater than or equal 2.80, the Law of Super Position can be applied for prediction of surface subsidence, caused by twin tunnels' construction

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