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With enlarging continuously of the fracture number of tiny springs, nonlinear characteristic of stress-strain curve will become more and more remarkable.
When load reaches a certain value, namely the damage of concrete develops to certain extent, the stress starts to lower although strain continually enlarges in the tiny unit body that the number of ruptured tiny springs is excessive.
Compressive stress and friction coefficient between steel and concrete vary in accordance with the thickness and grain size of the damaged concrete layer at the moment.
If ik represents the stiffness of the spring i, there exists 12 i n k k k k = = = = = L L , where n is the number of springs in a damage body.
(3) Where, K is initial bond stiffness of damage body, which involves the properties of damage body itself and is determined by the bond-slip curve fitted by experiment data [3]; D is damage variable and it is defined as the ratio of the number of damage springs and the total number of springs, namely ( ) ( ) ( )( ) 1 0 1 n N i i D n N H N H x dx ε ε δ ε δ →∞ = = = − → − ∑ ∫ .

In these engineering alloys, cracks are usually nucleated at multiple sites [1-5], namely, microstructural inhomogeneities, including metallurgical defects, grain boundaries, inclusions, second phase particles, porosities, and slip bands, when subjected to cyclic loading.
Because of the randomness of inherent microstructural inhomogeneities in an alloy, a large scatter exists in its stress vs. number of cycles to fatigue (S-N) curves.
In Al-Li alloy plates [6] and AA7075 T651 alloy plates [1,7], the fatigue properties were highly anisotropic, due to the pancake-shaped grain structure and strong texture in these plates, with the poorest being in the S direction and the best in the L direction, as the fatigue weak-links density was highest when loading along the S direction and was lowest along L direction.
Where N0 is the maximum possible number of cracks per mm2 generated in the surface area of 10×6 mm2 at the stress level close to the ultimate tensile strength (σs), i.e. maximum possible weak-links density (N0/(10×6 mm2)); k, constant; m, Weibull modulus; and σ0 is fatigue limit.
The pores including their number, size and distribution could be obtained by converting the pore 2-D statistics measured experimentally with optical microscopy into 3-D pore size distribution using an algorithm developed in this work in an A 713 cast Al alloy.

The in situ stress measurement methods based on the DME are commercial and permit large number of measurements.
Compared to the traditional in situ stress measurement, the methods based on the memory effect are commercial and permit large numbers of measurements.
One was the coarse-grained sandstone, which has already been developed and verified available[16].
Therefore, the crack cumulative number was recorded in the second loading as an additional identification method.
Cumulitive cracks number vs. stress in the second loading.

This paper will briefly describe the Cosserat continuum theory, the treatment of permeability changes with rock deformation and the coupling of the two-phase dual porosity fluid diffusion- flow model and present a number of examples highlighting the capability of the developed code in simulating the mining induced rock deformation, permeability changes and fluid diffusion and flow will be presented.
However, when closely spaced joints occur in large numbers such that the layer thickness becomes much smaller than the dimensions of the problem region, the discrete modelling of such a medium becomes tedious and expensive to perform.
Kozeny and Ber [19], Krumbein and Monk [20], De Wiest [21] attempted to establish a relationship between stress and permeability through a definition of hydraulic radius which is a function of grain diameter, porosity, grain shape and packing.
In this figure, mine measurements from a number of predrainage boreholes are presented.
A number of factors such as variation in local geology, gas content, and predrainage borehole completion and operation could have substantial effects on gas flow.

The conditions for obtaining highly mobile self-compacting concrete mixtures, in addition to the use of chemical additives, is a combination of such parameters as: • granulometric composition of the filler, providing a uniform volumetric distribution of particles by fractions; • the volume of cement paste, providing the necessary extension of the filler grains; • water content ensuring the fluidity of the system while maintaining sedimentation stability.
The sand should be round, the presence of needle grains is not allowed, as in their presence there may be problems with the mobility of the concrete mixture and its accelerated thickening.
When selecting the composition of the self-compacting concrete mixture, it should be borne in mind that the volume of the cement paste should be greater than the volume of voids, so that the grains of the large aggregate are completely surrounded by a layer of cement paste.
During the construction of the metro using self-compacting concrete, it was possible to reduce the number of concreters by 12 people, improve the quality of work and reduce the construction time.
Discussion and Conclusion Experience concreting of tunnels under the pre-routed tunnels proved very effective, greatly reduce the turnaround time and ensure high quality, reduce the number of concrete during concrete placement.

Since the waste was disposed of directly onto the alluvial sediments, a number of contaminants were shown to penetrate efficiently through the soil strata and eventually reach the groundwater system.
In the other words, Atterberg limits are important to describe the consistency of fine-grained soils or help to identify the state of soil [20].
The result of grain-size analysis showed that the soil consisted of 47.71% sand, 31.3% silt and 6.13% clay with the rest to be classified as gravel of 14.87%.
From the analysis, it clearly illustrated that the grain size of the local soil was silty sand which was closely with the result from previous study [25].
Basic properties of local soil at landfill Properties Results Moisture content 18.7 pH 4.45 Organic content (%) 0.41 Carbon content (%) 0.14 Atterberg limits (%) - Liquid limit 67.5 - Plastic limit 16.93 - Plasticity index 50.57 Specific gravity (N/m3) 2.33 Specific surface area (m2/g) 22.8 Cation exchange capacity (meq/100g) 3.15-3.19 Particle size distribution (%) - Sand ( > 0.063 mm) 47.7 - Silt (0.063 – 0.002 mm) 31.3 - Clay ( < 0.002 mm) 6.13 Heavy metal content mg/L (Background data) - As 0.43 - Cd 0.08 - Cr 0.23 - Cu 0.05 - Fe 14.7 - Mn 0.66 - Ni 0.03 - Pb 0.57 - Zn 2.56 Figure 6 present the percentage transmission (%T) in y-axis for various wave numbers in x-axis, cm-1 given by the FTIR spectrum of the soil.

The carbon appears to take shape of disordered amorphous or graphite-like layers surrounding the Ni3C or the evolving fcc nickel grains, respectively [4,5].
Right side: Prepared plug targets, number of plugs and the Ni:C surface ratios, which were achieved.
In case of XRD for example the signals overlap with that of the hexagonal nickel, if the Ni3C-grains are too small [17].
This is most probably caused by the decreasing grain size coming along with the expansion of the nickel lattice due to the incorporation of carbon (Fig. 5).
In the spectral range from 150 to 1150 cm1 a number of peaks can be observed.

Investigate the influence of sand ratio on concrete performance when the powder paste reaches the fixed number 350L, the concrete optimum performance.
(3)Coarse aggregate: coarse aggregate used in the test is gravel. 5 ~ 16mm and 16 ~ 25mm two kinds of grain size gravel mixed, blending ratio was 40%, 60%.
Table 3 The manufactured sand concrete mix Group number Water-cement ratio Water /L Superplasticizer /% Cb I1 0.6 170 0.7 283.33 I2 0.6 170 0.7 283.33 I3 0.6 170 0.7 283.33 I4 0.6 170 0.7 283.33 I5 0.6 170 0.7 283.33 I6 0.6 170 0.7 283.33 I7 0.6 170 0.7 283.33 I8 0.6 170 0.7 283.33 Table 3 The manufactured sand concrete mix (continued) Group number Cement /kg Fly ash (40%) Plus powder /kg Solid volume /L Sand ratio /% Powder paste volume /L I1 170 113.33 134.8 701.73 45 350 I2 170 113.33 124.6 701.73 43 350 I3 170 113.33 115.9 701.73 41 350 I4 170 113.33 116.0 701.73 39 350 I5 170 113.33 107.2 701.73 37 350 I6 170 113.33 72.5 701.73 35 350 I7 170 113.33 63.7 701.73 33 350 I8 170 113.33 50.8 701.73 31 350 Table 4 The performance of concrete mixture under the situations of different sand ratio when the water-cement ratio is 0.6 Group number Sand ratio (%) Superplasticizer (%) Slum (mm) Extension degree (mm) Description of workability I1 45 0.7 215 470 dry thick, no bleeding
Table 5 Compressive strength (MPa) Group number 28-day strength 56-day strength I1 25.00 33.39 I2 25.28 31.44 I3 24.79 29.79 I4 24.24 30.72 I5 24.98 32.87 I6 24.11 31.53 I7 24.45 33.34 I8 21.45 29.76 Fig. 5  Effect of sand ratio on compressive strength We can infer from the table, the strength variation of the I1, I2, I5, I7 four groups is very small, while other groups’ strength decreased. 

Research results about Qinling-Dabie collision belt shown that it finally completed collision and piece together in the late Jurassic, marginal residual sea in collision belt and both sides appeared completely, a large number of age data of syn-collision period metamorphism and magmatism were averagely 240～210Ma[21～25], which shown that the piece together completed in the late Jurassic.
The 210～200Ma was of post-orogenic stretching stage, combination of Chashan post-orogenic high alkali sinaite formed, for spotted medium-fine grained syenogranite in rock mass of Geji, SHRIMP U-Pb age of zircon was 205.7±1.4 Ma, 211.9±1.5 Ma[26], which represented the end of Indochina orogenic stage, meanwhile proved that piece together of south and north plates had finished in the late Triassic.
The general trend of magmatic evolution from early to late is that plagioclase and potash feldspar have relationship of growth and decline in mineral composition, content of SiO2 is decrease progressively as a whole in chemical composition, and that K2O+Na2O is increase progressively, change of rock texture as follow: fine grain—medium-fine grain—medium grain—medium-coarse grain—pegmatoidal texture.
This granite contains a great quantity of fine grain dioritic inclusions, in which there are not only have obvious magmatic texture but also have spotted acid granitic composition that have the same property with country rock and potash feldspar phenocrys.
Concerning to the age of lithospheric thinning, large numbers of researchers restrict time limit of structural system transition and lithospheric thinning in Mesozoic from different point of view.

COLOR STRUCTURE leptynite B-1/ B-2/ B-3 dark grey compact structure, particles meticulous, joint fissure no development granite H-1/ H-2/ H-3 black and white rock forming mineral particles coarser, joint fissure no development limestone S-1/ S-2/ S-3 light gray mineral grains meticulous, containing a small amount of cracks Analysis of Results AE analysis.
There into, node number of input layer is 11, respectively, rock acoustic emission ringing count, rise time, duration time, energy, amplitude, peak frequency, and the main IMF components.
Node number of output layer is 3, leptynite expressed in 001, granite for 010, limestone for 011, the mechanical noise for 100, and man-made noise use 101 instead.
According to the literature [5], the number of hidden layer node scope is for 4~9 that the design select 14.
Training adopts the RPROP algorithm, error objective function is 0.001, maximum number of iterations for 50000 times.