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Analysis on influencing factors of cement stabilized macadam base of compressive strength in Shenyang area Yan Xu1, a, Chunzhen Bai1,b , Yifang Zhang1,c , Xiao Liu1,dandDi Li1,e 1 Shenyang Jianzhu University, Shenyang, Liaoning province, 110168, China axy_zsl@163.com, b1039471842@qq.com, c786898732@qq.com, d10732420@qq.com, e1061825140@qq.com Keywords: grain size distribution, forming method, curing age, strength influencing factors Abstract.
Raw material properties Table 1 Raw material sampling Number Mixing station Construction route Particle size composition(cm) Stone origin 1 Shenbeicui gongbao Pingwang route,Nongwang engineering 1~3,1~2,0.5~1;attle Tieling 2 Shenyan Shenyan route 1~3,1~2,0.5~1;attle Fushun 3 Xinmin Jiangzhang route 1~3,0.5~1;attle Tieling 4 Hunnansifang Xinlibao route mixture, attle Liaoyang 5 Hunnanlixiang Shenli route, Yonghong route 6 Liaozhong Gaonen route Analysis of the formation mechanism of the strength of cement stabilized gravel Table 1 shows.
Construction mixture gradation curve reflects in less than 2cm of coarse particles, 1-2cm grain accounts for larger proportion, through the quality percentage is low, particle partial thick; Greater than 2cm of the gradation curve is located in the middle of the upper and lower curves.
Table 2 Different cement dosage on the influence on the strength of cement stabilized gravel base Number Mixture ratio Cement dosage （%） Molding method Unconfined compressive strength of the average value（MPa） 7d 28d 90d 1 gravel：attle =1:1 4.0 static pressure 3.41 3.88 5.86 2 gravel：attle =1:1 4.5 static pressure 3.68 3.95 6.03 3 gravel：attle =1:1 5.0 static pressure 3.86 4.04 6.24 From table 2 shows, the degree of compaction and distribution under the same conditions, the cement dosage had no significant effect on the compressive strength, When the cement dosage increased by 1%, the compressive strength of the 7 d growth is 0.45 MPa, the growth rate is 13%, the 28 d compressive strength growth is 0.16MPa, the growth rate is 4%, the 90 d compressive strength growth is 0.38 MPa, growth rate of 6.4%.Visible cement dosage effect on the strength is not obvious, and with the increase of age, strength increase value and ratio is to reduced compared with early strength.

It is also considered to be a ubiquitous element, since it has the ninth highest Clarke number among all the elements.
Iron (Fe) and manganese (Mn) are beta stabilizers for Ti alloys that are readily available, since they have the fourth and eleventh highest Clarke numbers, respectively.
Figure 2 presents the optical microstructures of the STQ alloys, in which only equiaxial beta grains are observed.
Some of these grains were evidently very large, being about 1 mm in size.
In each of the solution-treated and quenched alloys, only the beta phase was identified and equiaxial grains were observed. 2.

As the temperature increases, the helium atoms can move to grain boundaries, reducing the cohesion of the grain boundaries and causing grain boundary embrittlement.
At grain boundaries, no helium bubbles were observed in the specimens implanted with 1, 10, and 30 appm-He.
HCM12A steel has a lath-martensitic structure, and carbides are formed on lath boundaries and grain boundaries.
In both of the specimens, bubbles cannot be observed in matrix and grain boundaries.
At high temperatures, it is known that helium segregates at grain boundaries and causes grain boundary embrittlement.

Grain growth was observed with increase in film thickness.
A similar grain growth was expected with rise in film thickness/coating time, but results are almost reverse in this case (Figure 6).
The homogeneity of the grains on cool substrates is better as compared to the one at higher temperature as is evident from Figure 7.
After scratching the thin layer in two directions normal to each other, the tape is applied on hatched layer and pulled off to examine the extent/number of small squares stripped off either partially or fully from the substrate.
iv- Biasing as well as coating thickness has resulted in grain growth of the deposited film.

In the Yuan Dynasty (1271-1368 AD), the Luoyang-centered canal was transferred to Beijing-centered canal due to the needs of transporting grains.
This section of the Grand Canal was a water transport to conveying grain to the capital and a golden waterway connecting Beijing and Tianjin.
Many grain bins were located in this area, such as the Beicang grain bin, which is one of the streets name in the historic district of Tongzhou Zone in present.
Materials such as grains and silk were transported to Tianjin through the Southern Canal.
It was built in the late Qing Dynasty and consists of 5-bay courtyards with a total number of 278 halls (Fig. 6 and Fig. 7).

Solidification starts with the Al-phase growing through the Al2Cu layer within liquid channels at grain and subgrain boundaries as shown in the transverse section through the layer in fig. 2b.
If this process is accomplished fast, the newly formed lamellar eutectic grain will outgrow other neighboring grains with slow or sluggish alignment.
In fact the transition from maze-like to lamellar coupled growth governs early grain selection, the most competitive grains being those with fast alignment.
The SEM/BSE images show the pattern evolution in a small area of interest around a small net fault with equal number of four lamellae on both sides, the fault being marked with red dots in the lower line of images.
Within the area of interest but also within the entire grain the median value of the lamellar spacing amounts to lexp =5.7±0.4 µm with the spacing distribution ranging from lmin=4.8 µm to lmax=6.5 µm.

This plot shows that to within experimental error the grain "size" cannot be estimated using this method (the zero value of the intercept means that the grain size is of the order of a micrometer).
An increase of the linewidth with milling time was observed, as indicated in Fig.4, which is attributed to the increasing number of defects and amount of strain.
(a) Oxygen map of a Fe 224h grain.
(b) Image of the grain taken at 539.78 eV.
The spectra could be measured for the individual parts of the grain (Fig 8b).

Another is that nanostructured metals often contain a significant number growth twins under certain synthesis conditions [6-8].
Therefore, some special mechanical properties such as high strength, high strain rate sensitivity are obtained by the introduction of nanoscale growth twins into ultrafine-grained Cu [9-11] without any concomitant reduction in the ductility in contrast to coarse-grained Cu.
(a) Cross-sectional optical micrograph of Cu with a high density of growth twins (the inset shows an inverse pole figure for the growth direction of the grains).
Each columnar grain contains a high density of lamellar structure.
TB migration has been studied before in coarse-grained Cu [41].

AFM produced images showed SC-PEN grains with sizes ranging from 0.2 to 0.4 μm, and VT-PEN grains ranging from 0.1 μm to 0.2 μm.
Peak intensity shown on XRD patterns (Fig. 2) mirrored the grain size of the PEN samples observed in AFM images (Fig. 3).
SC-PEN presented higher peak intensity while having larger grains due to its surface roughness of 11.61nm, while VT-PEN, which has smaller grains, has its peak intensity lower than that of SC-PEN due to its higher surface roughness of 27.46 nm.
XRD patterns of (a) VT-PEN and (b) SC-PEN Samples with Diffraction Peaks and Grain Orientation Identified.
Bromine doping has good effect on the sudden increase in Voc, meaning greater number of electrons are produced and reached the counter electrode.

The equiaxed grains can be obtained by conventional cast technology, but most of catastrophic events are resulted from creep deformation and microcracks that are related to the grain boundaries normal to the stresses axes.
DZ4 has columnar grains with preferred orientation parallel to the stresses axes, thus increases the plasticity and ductility of alloy by eliminating most boundaries perpendicular to the stresses axes.
The “peak flash temperature” can be used to evaluate the number of active cutting points, contact length and dynamic cutting-point density that will be useful for optimization of grinding wheel topography.
This indicates that the plastic sideflow plowing of the DZ4 alloy around abrasive grains is enhanced along with the chip adhesion and the alloy is extruded to the side of abrasive grains.
With the onset of grinding burn, DZ4 exhibits special metallurgical changes different from that of the general nickel based alloy with equiaxed grains.