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Assessment of Factors Affecting the Final Value of «volume loss» by TBM tunneling {0><}0{>Alexey A.
affecting the increase of this parameter, and their quantitative assessment is given in this paper.<0} {0>Применение предложенной в статье методики позволяет оперативно оценить влияние проходческих работ на существующие подрабатываемые объекты с учетом основных влияющих факторов.<}0{>The method proposed in this paper makes it possible to promptly assess the impact of tunneling operations on the existing underworked structures with account of basic influencing factors.<0}{0>Ключевые слова:<}94{> Introduction At present, the development of large cities and megapolises is impossible without developing their underground space.
The paper provides the analysis of the basic factors affecting the “construction clearance” value, their quantitative analysis and the simple expressions constructed in order to determine the design value of the “construction clearance”: , (1) where u0 is the value of double construction clearance due to the difference between TBM rotor diameter and tunnel lining outside diameter, taking into account that the “construction clearance” is filled with grout; u1 is the displacement caused by the subsidence of the TBM head by gravity; u2 is the displacement due to soil deformations at the face; u3 is the displacement due to lining deformations underground pressure.
In order to determine the compressed strata depth, a design model was developed to take into account the basic physical and mechanical properties of soil mass, its stratification and basic characteristics of shield-type tunnel-boring machines.
(6) where k1=18÷20 – factor that depends on soil properties; Нс – compressed strata depth, m; η – shield subsidence, mm; D – outside diameter of the TBM head, m; G – weight of the TBM head, kN; G1 – weight per linear meter of the TBM head, kN/m; L – length of the TBM head, m; γi and hi – bulk density of the i-th soil layer and layer thickness, respectively; γsoil – thickness-averaged soil bulk density, kN/m3.

Hard Thermosetting Polyurethane Plastic Degradable Test and Its Influential Factors Zhifeng LIU 1, a, Jian ZHAO 1,b , Hui XIA1,c, Zhongwei WU 1,d 1 School of Mechanical and Automotive Engineering, Hefei University of Technology, Hefei China 230009 apeak.liu@263.net, b136212178@qq.com, c 872991151@qq.com,d9458319@qq.com Keywords: mechanical and physical methods; hard polyurethane; ATR-FTIR; degradation Abstract.
Finally, the cutting blades of the millstone edge begin to rotate, through collision and impact of the powder particles under the action of centrifugal force, materials are further degradated and softened [2]. 2 3 1 Fig. 1 Three-dimensional structure of shear shredders (1) Central area (2) Millstone area (3) Blade area 1.2 Orthogonal test arrangement To analyze the influence factors of polyurethane degradation, at the early stage of experimental basis, experimental plane parameters, test the inherent properties and external environment is the main reason affecting the degradation speed in which the increase of rotating speed will make the material pressed by shearing, extrusion and friction; extension of time can make material accumulate more mechanical energy, material activity further enhanced; The increase of the feed quantity can reduce the clearance between materials and the cavity wall, meanwhile it can increase the friction; ATR-FTIR test results will be different in
different sizes, so the changes in particle size should be also treated as the factors.
The pulverizer considers three factors and one by one test process is more cumbersome, so in the actual test we base on the orthogonal experiment table to arrange test, without affecting the accuracy of the results.
= （1） is the rate of mass loss, is the increases rate of specific surface. 3.2 The analysis of the degradation factors The machine’s parameters and external environmental factors will affect the degradation effect and rate.

Zeolites not only improve gases permeability of polymer but also improve mechanical properties and thermal properties. [2-4] However, the different polarity of PBAT and zeolite affect the dispersion of zeolite in polymer matrix. 3-aminopropyl trimethoxysilane was selected as the coupling agent to improve the compatibility between zeolite and PBAT.
Results and Discussion Mechanical properties of PBAT film Mechanical properties have evidently shown a major effect on the quality of film packaging.
Diffusion and adsorption abilities depend on many factors.
Zeolite5A influenced on mechanical properties.
Zeolite5A facilitated a higher influence on mechanical properties of PBAT film than the zeolite 13X.

Research on properties of materials based on extension evaluation method Yaolin Liu Keywords: Materials, Mechanical Properties, Matter-element Theory, Extension Evaluation Abstract.
It is often used to evaluate things with many affecting factors.
Analysis on factors of properties of materials There are many kinds of factors of properties of materials, including Chemical composition,Heat treatment condition,Physical properties and Mechanical properties etc.
During the selection of materials, the mechanical properties of materials are much analyzed, it has the following factors.
It is suitable for the evaluation with many Influence factors.

Assessment of Mechanical Properties and Transformation Behavior of Locally-made Ni-Ti Alloys Used in Orthodontics N.
The purpose of this study was to assess the mechanical properties and phase transformation of 50.7Ni-49.3 Ti (at%) alloy (NT) and 45.2Ni-49.8Ti-5.0Cu (at%) alloy (NTC), cold-rolled with various percent reductions.
The results showed that locally-made Ni-Ti alloys have various transformation behaviors and mechanical properties depending on three principal factors: chemical composition, work-hardening (the percent reduction) and heat-treatment temperature.
After removing any oxide layers and surface contaminants by mechanical polishing, the specimens were annealed at 400°C and 600°C in a vacuum heat treatment furnace for 1 hour in order to study the influence of recrystallzation on the mechanical properties and transformation behavior of the alloys.
Optical micrograph (20X) showing grain structure of NTC with 20% reduction and 400°C heat treatment Summary The principal factors affecting the transformation behavior and mechanical properties of Ni-Ti alloys are chemical compositions, working history and heat treatment temperature.

Microstructure characteristics and mechanical properties of the rapid solidified ribbon of 7A09 aluminum alloys are studied by means of X-ray diffraction (XRD), scan electron microscopy (SEM) and hardness measurement.
The results show that the rotate speed of the roller is the key factor affecting the ability of the forming ribbon.
All above are beneficial to increase the mechanical properties, to improve machining performances and to enhance corrosion resistance of the alloys [1~4].
Microstructural features and mechanical properties of the rapid solidification ribbon of 7A09 aluminum alloys are studied.
Conclusions (1) The most important factor affecting the forming ability of ribbon is the rotating speed of the cooling rotor.

Influence of Processing on Mechanical Properties of Hydroxyapatite Marize V.
In the present work, mechanical properties of a stoichiometric hydroxyapatite (HA), synthesized by hydrothermal method, with 1.66 Ca/P molar ratio are investigated as a function of the processing parameters.
The HA chemical nature and the processing parameters used affect directly the compressibility behavior which strongly influences the ceramic processing and the final sintered HA mechanical properties [3].
According to Snyders and co-workers [7], the main factors which influence the mechanical properties of HA are the density, the shape of the pores, the crystallinity, the grain size and the purity of the HA phase.
Also the compaction pressure and sintering temperature exerts strong influence on the mechanical properties of HA [8].

Welded joint is a mechanical heterogeneous body, which is composed of base metal, weld metal and heat affected zone (HAZ).
The strain rate near crack tip reaches 10 3 under the impact velocity of 5m/s, so dynamic properties under corresponding strain rate should be used in dynamic analysis.
Welded joint is a mechanical heterogeneous body, which is composed of base metal, weld metal and heat affected zone (HAZ).
In this paper, dynamic J-integral is used to characterize the dynamic fracture behaviour of welded joints with mechanical heterogeneity, and the effects of geometry factors on dynamic J-integral is studied.
Base Metal σyd[MPa] n Weld σyd[MPa] n 620 10.32 496 8.09 Table 1 Mechanical properties of the computational model The present 3D FEM computations are performed using a commercial FEM code of MARC.

With a much smaller volume fraction in the composite, nanoparticles are able to provide the composite material with strength enhancements, without affecting other properties.
Mechanical Properties.
In addition to advantages in mechanical properties, PCNC possess improvements in other properties such as gas barrier properties and thermal properties.
Since the filler weight ratio is very small, this occurs without affecting other favorable properties.
These two factors were studied extensively by Xu et al. [15].

In this manuscript, we studied the mechanical properties of the cement-lime-treated loess soils with different weight ratio.
The physical indices and strength properties of these samples tested are analyzed in detail and their main influence factors are also investigated.
There are many factors affecting the optimal water content of the samples, including soil properties, the value of compaction work, etc.
There are other factors, like the dry density, curing enviroment, etc., affecting the stregnth of the samples treated by lime-cement or cement,which should be investigated further.
(2) The strength of the samples are affected by many factors including treated materials, compatcion work, water content, and age.