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The pore structure of concrete is a very important material property influencing the durability of concrete.
Acknowledgement This paper was elaborated with the financial support of the Czech Science Foundation project GA13-18870S and European Union's "Operational Programme Research and Development for Innovations", No.
CZ.1.05/2.1.00/03.0097, as an activity of the regional Centre AdMaS "Advanced Materials, Structures and Technologies".
Russian Journal of Nondestructive Testing, 46 (2010), 226-233

Introduction Concrete is one of the most widely used construction materials.
For concrete, compressive softening is not an inherent material property.
The nonlinear behavior of concrete materials has been extensively studied in both experimental and theoretical investigations.
For a homogenous and linear elastic material, the Poisson's ratio is a constant.
Acknowledgment Financial Support from 973 Project under 2009CB623200 and National Natural Science Foundation of China under 50808043 is acknowledged.

As a kind of organic polymer materials, asphalt is extremely easy aging under natural environment.
However, the ultraviolet aging of asphalt is still stay in science exploration research stage.
Raw materials and test methods 1.1 Raw materials The asphalt of the test: Esso 90 # asphalt matrix, Karamay 90 # asphalt matrix, "Shell" high modulus modified asphalt and "Shell" grams of crack king modified asphalt.
And if the G*sinδ of asphalt material is comparatively large, the deformation of the pavement under traffic load will not quickly recover, thus it is easy to form cracks and other diseases under the continuous action of vehicle load. (2) After ultraviolet aging, the fatigue cracking resistance of these asphalts are significantly deteriorating.
References [1] Dai zheng: Road asphalt aging behavior research under the action of ultraviolet, China Journal of Petroleum Asphalt 2014;28(1) [2] Wang Jia ni, Cui zhong jun: Several kinds of asphalt anti ultraviolet aging measures on performance contrast test research

China; 3College of Life Science and Technology, Guangxi University, Nanning 530005, P.R.
Introduction Bagasse pulp, one of the major agro-residues, can be used as an important source of raw material for pulp and paper manufactures, playing an important role in solving the problem of raw materials shortage and it is being widely applied to the pulp and paper industry, which also brings good economic profits and social benefits.
In Guangxi, (China) where sugarcane is the abundantly grown crop, bagdsse is one of the major cheap raw materials available for paper making.
Experimental Materials.
Acknowledgments This study was supported by the National Natural Science Foundation of China (Grant 20066001).

a b Fig. 1 Damaged purging plug a-Work face of purging plug produces peeling ; b-Fracture in a certain distance from the work face Despite having been relatively well studied from aspects of both materials and structures, no attempts have been made to explore the effect of air way structure to the performance of purging plug.
Physical Properties and Boundary Conditions 3.1 Physical Properties Physical properties of various materials in calculation model are shown in Table 1[1].
Acknowledgements Thanks are due to the National Natural Science Foundation of China (NO. 51372231) for the financial support.
Hubei: Wuhan University of Science and Technology, 2009
Journal of Wuhan University of Technology, 2010, 32(7): 8-11

Introduction The rubber composite materials have broad field of application and development prospect, including the lower price of filling type of thermal rubber, which are processed and formed easily, and that are widely used in aerospace, aviation, electronics, electrical appliances, and so on[1-3].
But sometimes, the single-component material filling is too relatively simple on the material properties, which is not easy to change and overcome the gaps and weaknesses in the application.
Otherwise, in this paper, the detail analysis of the orthogonal designs combined with the tests are carefully and fully considered, especially in the valued details, thus, the blindness and lose of the testing might largely be decreased, meanwhile, the usability and expansion of the testing results might largely be enhanced, which it is an important issue in practicality of the orthogonal experiment design for the composite rubber materials.
As it has been funding supported by project (51001117), NSF of Beijing (3132024, 3120001), Distinguished Young Scholars of NSFC (51125023)and innovation fund of Academy of Armored Force Engineering, we are deeply grateful to the National Nature Science Foundation of China and Academy of Armored Force Engineering.
[3] Zhou Wenying, Qi Shuhua,Tu Chunchao,et al.Effect of the particle size of Al2O3 on the properties of filled heat~conductive silicone rubber[J].Journal of Applied Polymer Science,2007, 104(2):1312~1318

Fracture-Mechanics Behaviour of Ceramic Foam with Macroscopic Stress Concentrator upon the Tensile Test Oldřich Ševeček1,a, Zdeněk Majer1,b, Luca Bertolla1,2,c, Zdeněk Chlup2,d and Michal Kotoul1,e 1 Brno University of Technology, Institute of Solid Mechanics, Mechatronics and Biomechanics, Technická 2, 616 69 Brno, Czech Republic 2 Institute of Physics of Materials, Academy of Sciences Czech Republic, Žižkova 22, Brno, Czech Republic asevecek@fme.vutbr.cz, bmajer@fme.vutbr.cz, cbertolla@ipm.cz, dchlup@ipm.cz, ekotoul@fme.vutbr.cz Keywords: Ceramic foam, fracture, stress concentrator, FEM, Voronoi tessellation, tensile test.
Introduction The growing exploitation of ceramic foams with open cell porosity in a great number of industrial branches and/or as bone replacement materials, has instigated experimental and theoretical studies of their mechanical behaviour.
Young’s modulus of the ceramic material was considered to be Ebulk=90GPa and Poisson´s ratio nbulk=0.25 (corresponding to source material of “VUCOPOR®A” - Al2O3 based ceramic foam).
A financial support of the Czech Science foundation under the project no. 17-08447Y is gratefully acknowledged.
Kraynik: Journal of Applied Mechanics Vol. 64 (1997), p. 787-794 [2] H.X.

The compound ratio design of shotcrete and simulation experiment Information of the constituent materials of the shotcrete: cement is the type of P.O42.5R, the sand is mechanism sand, Mx=2.7, the content of micro fines is 12%, the size of gravel ranges from 5mm to 15mm continuously, TK-SP polycarboxylic acid type water-reducer, BASF alkali-free liquid accelerator.
Figure 1 Different conservation of the environment, the compressive strength of shotcrete contrast The improvement of compressive strength in hot-humid environment Regarding 70℃damp-heat environment as representative conditions, studying how does admixture or fiber material effect shotcrete compressive strength.
Acknowledgements We would like to acknowledge the support of National Natural Science Foundation (51008253) and the Fundamental Research Funds for the Central Universities (SWJTU12CX072) and Student Research Training Program of Southwest Jiaotong University(120113) during the research.
[2] ACI Committee 506, Specification for materials, proportioning and application of Shotcrete (ACI506-77).
[4] Xie Youjun, Liu Baoju, Liu Wei: Journal of Railway Science and Engineering Vol.1 (2)(2004),p.46 (In Chinese)

Experimental procedure Three kinds of stainless steel widely used for orthopedic surgical tools and jigs were used as workpiece materials.
Little heat energy penetrates into the material, and the material removal by melting and evaporation occurs adjacent to the surface [6].
In the EB polishing of some materials such as metal mold steel and titanium alloy, a remarkable improvement in corrosion resistance has been found [6, 7].
Acknowledgments This study was financially supported by the Program of Collaborative Development of Innovative Seeds (No. 6010014) in Japan Science and Technology Agency, and also partly supported by the Grant-in-Aid for Scientific Research of Japan Society for the Promotion of Science (No.20360069).
[7] A.Okada, Y.Uno, K.Uemura, P.Raharjo and J.A.McGeough: IMechE Journal of Engineering Manufacture, Vol.221 (2007) p.173.

Zuk [1] investigated the thermal behavior of several concrete bridges and found that the temperature distribution was affected by air temperature, wind, humidity, intensity of solar radiation and material type.
Heat transfer analysis As far as a concrete bridge subjected to thermal radiation is concerned, the temperature field T of a concrete component at any time t can be expressed by the well-known Fourier equation [6-7]: (1) in which: is the temperature of structural component;is time instant; ,andare the thermal conductivity of material in x, y and z direction respectively; is the density of material;is the heat of material ;is the time rate of heat generated per unit volume (eg. the heat of hydration).
Acknowledgements The writers are grateful for the financial support from the National Natural Science Foundation of China (Grant 51178366), the Fok Ying-Tong Education Foundation (Grant 131072) and the Construction Technological Project of the Hubei Province (EJianWen[2011]No.154-Project.115, EJianWen[2011]No.154-Project.118).
Stone : Journal of Mechanical Engineering Science, 20(1978), p. 93-100
Mirambell : ACI Materials J., 89 (1992), p. 139-145.