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Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Ocean University is the property of Editorial Department of Journal of Shanghai Ocean University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The water-cement ratio- packing density and specific surface area are important factors that influence backfill strength. However- few studies have investigated the significance of these influencing factors. Hence- uniaxial compressive strength tests were carried out on test blocks aged 3 d- 7 d and 28 d using a 3-factor 5-level orthogonal design. A variance analysis was performed on the experimental results. The results from this statistical analysis indicated the following F-value ratios for the three factors(water-cement ratio: packing density: specific surface area) at different ages: 3 d(698.404: 26.148: 0.910)- 7 d(862.626: 35.465: 1.286) and 28 d (1 585.404: 31.695: 1.338). According to the analysis results- the influencing factors had the following order of significance: water-cement ratio > specific surface area > packing density. Due to the small F-values of the specific surface area and packing density- these variables were not considered as factors affecting strength when establishing a strength prediction model. To obtain a backfill with the maximum strength- the optimal mixture had a 1.2 water-cement ratio- a specific surface area of 410 m ² / kg- and a packing density of 0.6% . To study the relationship between the water-cement ratio and strength- the water-cement ratio in the optimal mixture was varied- and 30 groups of strength tests were performed with samples containing different water cement ratios after ageing for 3 d.7 d and 28 d. Based on the experimental results-a combined model was established for predicting strength at 3 d.7 d and 28 d with a combination of grey theory-fuzzy set theory and Markov theory. The measured values were plotted on the same scatter diagram as the values predicted with the GM(1-2) model-the regression analysis model and the combined model. A subsequent analysis verified that the combined model had higher accuracy and robustness than other models. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the effects of mixed aggregate ratio and particle size gradation on the rheological properties of the slurry，firstly， the particle size of the waste rock， rod mill sand and the mixture of them commonly used in filling was analyzed， and the corresponding characteristic particle size was obtained.Secondly， the slurry with different aggregate ratios and different mass concentrations was prepared by rheometer. The rheological parameters were fitted by H-B rheological model. Then，the rheological parameters and rheological properties were analyzed， and the correlation between aggregate size distribution and rheological properties of slurry was studied based on least square method.Finally， the stability of slurry is discussed， and the critical particle size range of non-settling segregation of aggregate is 13.8~21.6mm by establishing mechanical model. The test results show that the yield stress and apparent viscosity of the slurry increase with the increase of slurry mass concentration. The rheological properties of slurry show different model characteristics with the increase of shear rate. The correlation between rheological properties parameters of slurry and aggregate particle size distribution increases with the increase of characteristic particle size. With the increase of mass concentration， the correlation between slurry yield stress and aggregate size gradation gradually decreases， while apparent viscosity gradually increases. The mass concentration and aggregate size gradation have a great influence on slurry stability. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)