The Japanese flounder is one of the most widely farmed economic flatfish species throughout eastern Asia including China, Korea, and Japan. Edwardsiella tarda is a major species of pathogenic bacteria that causes ascites disease and, consequently, a huge economy loss for Japanese flounder farming. After generation selection, traditional breeding methods can hardly improve the E. tarda resistance effectively. Genomic selection is an effective way to predict the breeding potential of parents and has rarely been used in aquatic breeding. In this study, we chose 931 individuals from 90 families, challenged by E. tarda from 2013 to 2015 as a reference population and 71 parents of these families as selection candidates. 1,934,475 markers were detected via genome sequencing and applied in this study. Two different methods, BayesCπ and GBLUP, were used for genomic prediction. In the reference population, two methods led to the same accuracy (0.946) and Pearson's correlation results between phenotype and genomic estimated breeding value (GEBV) of BayesCπ and GBLUP were 0.912 and 0.761, respectively. In selection candidates, GEBVs from two methods were highly similar (0.980). A comparison of GEBV with the survival rate of families that were structured by selection candidates showed correlations of 0.662 and 0.665, respectively. This study established a genomic selection method for the Japanese flounder and for the first time applied this to E. tarda resistance breeding.

Based on the urban shantytown renovation project in Hongguang Town, Helan County, Ningxia, in Northwest China, the influence of fly ash and silica fume admixture on the mechanical properties of Self-compacting Concrete (SCC) was tested and analyzed in this work. The experimental tests including compressive strength, splitting strength, triaxial strength and an ultrasonic nondestructive test. Furthermore, the Back Propagation (BP) neural network algorithms were established. The results show that there is an obvious difference between the development law of compressive strength of SCC and that of ordinary concrete. The splitting pressure ratio of SCC is 1/10 to 1/8, while that of ordinary concrete is 1/13 to 1/10. Moreover, the peak strain, peak stress and initial stiffness of SCC increase with the increase of the confining pressure when compressed from three directions. In addition, the ultrasonic amplitude of SCC can reflect the changing laws of its compressive strength. As a conclusion, the addition of fly ash and silica fume increases the splitting pressure ratio of SCC. More importantly, the compressive strength formula for SCC with silica fume and a low content of fly ash is proposed, and the model equation between the amplitude and compressive strength is given. This study provides a reference for the mixture ratio of fly ash and silica fume in the application of SCC.Compared with ordinary concrete, SCC has better properties in terms of realizing labor-saving concrete pouring to improve the quality and speed of construction, and in terms of upgrading the living environment of surrounding residents with reduced noises. Moreover, it also helps solve the steel tube vibration problem during construction [18][19][20]. Previous research [21][22][23][24][25] studied the effects of different amounts of steel fibers and polypropylene fibers on the mechanical properties of self-compacting reactive powder concrete. In particular, fewer examples of conventional triaxial testing on SCC mixed with fly ash and silica fume were reported. For instance, Farnam [26] studied the mechanical properties of 4 kinds of mortar-impregnated concrete specimens with varied steel fiber contents (0%, 2%, 5%, and 10%) under 4 sorts of confining pressures, and Giorgio proposed a micromorphic, non-linear 3D model [27]. In addition, the implementation of the national capacity-reduction policy and the clean utilization of coal make fly ash a prominent resource at present. Therefore, there is still large space for the research on SCC with fly ash and silica fume. Based on the urban shantytown renovation project in Hongguang Town, Ningxia, we used fly ash as an admixture for SCC in this work. There are many non-destructive methods used for analysing the concrete structure, such as the Digital Image Correlation (DIC) method [28] and the Ultrasound method. The amplitude was measured by ultrasonic wave, and the relationship between amplitude and compressive strength was established in this work. Furthermore, the relationship between the fly ash and ...

In order to study the axial compression performance of the T-shaped multi-cavity concrete-filled steel tube shear wall, first, three specimens were designed to perform the axial compression test. Then three-dimensional finite element analysis by the ABAQUS software was used to obtain the axial bearing capacity of the shear wall with different parameters. According to the results of the finite element model, the computational diagram in the limit state was obtained. The diagram was simplified into the core concrete in the non-enhanced area that was not constrained by the steel tube and the core concrete in the enhanced area that was uniformly constrained by the steel tube. Finally, a new practical equation for calculating the axial bearing capacity of a multi-cavity concrete-filled steel tubular shear wall was deduced and proposed based on the theory of ultimate equilibrium. The calculation results of the proposed equation were in good agreement with the finite element results, and the proposed equation can be used in practical engineering design.

In this paper, five groups of C40 fly ash and silica fume self-compacting concrete (SCC) mix proportion tests and in-line multi-cavity steel tube bundle self-compacting concrete shear wall axial compression performance tests and numerical simulation are completed and presented. The influence of fly ash and silica fume additions on SCC mechanical properties and the filled in-line multi-cavity steel tube bundle shear wall mechanical properties are analyzed and studied. With an increase in the fly ash content from 10% to 40%, the compressive strength of self-compacting concrete increases firstly and then decreases. When the fly ash content is 30% and the silica fume content is 4%, the compressive strength of the 28 d age self-compacting concrete is the highest and the compressive strength formula of the wrapped curing SCC is proposed. The failure of steel tube bundle is multi-wave buckling failure. As the SCC is most obviously affected by the collar at the corner point of the steel tube bundle, its compressive strength is 110 MPa, and is 96 MPa higher than the concrete at the middle point of the web. The deformation resistance of SCC is obviously enhanced by the confinement effect.