Properties of Gobi Aggregate and Sulfide-Rich Tailings Cemented Paste Backfill and Its Application in a High-Stress Metal Mine

This experiment studied the influence law of the strength of CPB affected by tailings content, Gobi aggregate content, cement content, and slurry concentration. The results show, for the CPB with concentration of 77%, when the addition amount of cement reaches 20%, the addition amounts of tailings and Gobi aggregate change within the ranges of 12∼24% and 56∼68%, respectively. The strength of CPB has been gradually improved when the addition amount of Gobi aggregates decreases and the addition amount of tailings increases. In this case, the slump of CPB changes within the range of 26.5 cm∼26.9 cm while the strength of CPB changes within the range of 4.021∼6.845 MPa. Considering future utilization value of tailings, the addition amount is finally set at 16% in production, and the addition amount of Gobi aggregate is set at 64%; namely, tailings: Gobi aggregate = 20 : 80. When the addition amount of cement is 20% (cement/(tailings + Gobi aggregates) = 1 : 4), the strength of CPB reaches 5.62 MPa which meets the production requirement. When the heading machine is used for tunnelling mine roadway in bottom backfill of VCR stope, no collapse or delamination occurs without support, showing good stability and integrity of backfill. When the adjacent stope ore is mined, the backfill with cement content of 11.1%, 14.3%, 20%, and 25% is exposed. In the process of mining, no collapse or delamination occurs. Therefore, the proportion of various backfill materials applied in production is reasonable, being verified by the experiment and field test.

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Electromagnetic wave-based measurement techniques to study the role of Portland cement hydration in cemented paste backfill materials

International Journal of Mining Reclamation and Environment ◽

10.1080/17480930.2012.639193 ◽

2012 ◽

Vol 26 (1) ◽

pp. 3-28 ◽

Cited By ~ 12

Author(s):

Dragana Simon ◽

Murray W. Grabinsky

Keyword(s):

Electromagnetic Wave ◽

Portland Cement ◽

Cement Hydration ◽

Measurement Techniques ◽

Cemented Paste Backfill ◽

Backfill Materials ◽

Paste Backfill ◽

Portland Cement Hydration

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Investigating the Effect of Solid Components on Yield Stress for Cemented Paste Backfill via Uniform Design

Advances in Materials Science and Engineering ◽

10.1155/2018/3839174 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Yong Wang ◽

Aixiang Wu ◽

Lianfu Zhang ◽

Fei Jin ◽

Xiaohui Liu

Keyword(s):

Yield Stress ◽

Mass Fraction ◽

Cement Content ◽

Uniform Design ◽

Free Water ◽

Experimental Program ◽

Cemented Paste Backfill ◽

Free Water Content ◽

Key Factor ◽

Paste Backfill

Cemented paste backfill (CPB) technology has been applied quite popular around the world. Yield stress is a key factor determining whether CPB could be transported. In order to reveal the effect of solid components on yield stress of CPB, a uniform design experimental program (four factors and six levels) was conducted to test the rheological property of a mine’s CPB. The tested four factors including mass fraction, cement versus other solids ratio, coarse tailings, and gravel contents were considered during the experiment design. Likewise, six experimental levels were given to each factor. Results of the test show that yield stress increased with the mass fraction and cement content. However, the trend reversed for the content of coarse tailings and gravel. Contribution of the four factors to yield stress in descending order is mass fraction > content of gravel > content of coarse tailings > cement versus other tailings ration. Effect of solid components on the yield stress of CPB is mainly due to the different flocculation structure inside the CPB. These various flow structures result in the different free-water content of CPB, leading to a different yield stress value.

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Investigation of some controllable factors that impact the stress state in cemented paste backfill

Canadian Geotechnical Journal ◽

10.1139/cgj-2014-0321 ◽

2015 ◽

Vol 52 (12) ◽

pp. 1901-1912 ◽

Cited By ~ 29

Author(s):

James P. Doherty ◽

Alsidqi Hasan ◽

Gonzalo H. Suazo ◽

Andy Fourie

Keyword(s):

Pore Water ◽

Pore Water Pressure ◽

Cement Content ◽

Water Pressure ◽

Cemented Paste Backfill ◽

Total Stress ◽

Rest Periods ◽

Rate Of Increase ◽

Controllable Factors ◽

Paste Backfill

This paper presents in-stope measurements of total stress and pore-water pressure at strategic locations within three underground stopes at the Raleigh mine site (Western Australia) that were filled with cemented paste backfill (CPB). The three stopes were very similar in shape. Key differences among the stopes were the filling and resting schedules, the barricade drainage systems used, and the cement content of the CPB. Data from the stopes are compared to determine which controllable factors most significantly influence barricade pressures during and after filling. The most significant factor was the scheduling of rest periods between filling, with even very short pauses in filling dramatically reducing the rate of increase of pore-water pressure and total stress with increasing height of fill.

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Fluidity and Mechanical Behavior of Cement Solidified Lead-Zinc Mine Tailings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.898.383 ◽

2014 ◽

Vol 898 ◽

pp. 383-386 ◽

Cited By ~ 1

Author(s):

Chun Lei Zhang ◽

Shun Cai Wang ◽

Fan Lu Min

Keyword(s):

Mine Tailings ◽

Cement Content ◽

Strength Increase ◽

Cemented Paste Backfill ◽

Curing Time ◽

Test Results ◽

The World ◽

Paste Backfill ◽

Lead Zinc ◽

Zinc Mine

Cemented paste backfill method has been widely used in many modern mines throughout the world due to the increasingly stringent environmental regulations and short of disposal land. This study presents experimental results on the use of Portland cement in the solidification of Pb-Zn tailings in China. Test results show UCS strength increase lineally with cement content, tailings concentration, and curing time, respectively. There exist a minimum cement content and tailings concentration to produce obvious strength. The fluidity decrease quickly with cement proportion and tailings concentration, under the satisfying of a minimum pumping fluidity, the increase of tailings concentration can effectively reduce the cement consumption so as to decrease the treatment cost.

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Dynamic tests of cemented paste backfill: effects of strain rate, curing time, and cement content on compressive strength

Journal of Materials Science ◽

10.1007/s10853-011-5449-0 ◽

2011 ◽

Vol 46 (15) ◽

pp. 5165-5170 ◽

Cited By ~ 36

Author(s):

Sheng Huang ◽

Kaiwen Xia ◽

Lan Qiao

Keyword(s):

Compressive Strength ◽

Strain Rate ◽

Cement Content ◽

Cemented Paste Backfill ◽

Curing Time ◽

Dynamic Tests ◽

Paste Backfill

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3D Numerical Modelling of the Application of Cemented Paste Backfill on Displacements around Strip Excavations

Energies ◽

10.3390/en14227750 ◽

2021 ◽

Vol 14 (22) ◽

pp. 7750

Author(s):

Krzysztof Skrzypkowski

Keyword(s):

Numerical Modeling ◽

Cement Content ◽

Cemented Paste Backfill ◽

Mining Method ◽

3D Numerical Modeling ◽

Compressibility Coefficient ◽

3D Numerical Modelling ◽

Paste Backfill ◽

First Time ◽

Cylindrical Samples

This article presents laboratory and spatial numerical modeling of cemented paste backfill. The first part of the research concerned laboratory tests of a mixture of sand, water, and variable cement content (5%, 10%, and 15%). The density and curing time of the mixture were determined. Moreover, cylindrical samples with a diameter of 46 mm and a height of 92 mm were constructed, for which compressive and tensile strength were calculated after one, two, three, and four weeks. The second part of the research concerned 3D numerical modeling with the use of RS3 software. For the exploitation field with dimensions of 65 m × 65 m, a strip-mining method was designed. The main objective of the research was to determine the changes in displacements around the haulage room and transportation roadway located in the immediate vicinity of the exploitation field. For the first time in numerical modeling, a two-sided strip method was used for the four stages of mining the ore deposit where the post-mining space was filled with a cemented paste backfill. Based on this research, the compressibility coefficient was determined.

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Feasibility study and performance optimization of sand-based cemented paste backfill materials

Journal of Cleaner Production ◽

10.1016/j.jclepro.2020.120798 ◽

2020 ◽

Vol 259 ◽

pp. 120798 ◽

Cited By ~ 3

Author(s):

Nan Zhou ◽

Jixiong Zhang ◽

Shenyang Ouyang ◽

Xuejie Deng ◽

Chaowei Dong ◽

...

Keyword(s):

Feasibility Study ◽

Performance Optimization ◽

Cemented Paste Backfill ◽

Backfill Materials ◽

Paste Backfill ◽

And Performance

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Predicting the Isotropic Volumetric Compression Response of Hydrating Cemented Paste Backfill (CPB)

10.21203/rs.3.rs-957254/v1 ◽

2021 ◽

Author(s):

mohammadamin jafari ◽

Murray Grabinsky

Keyword(s):

High Stress ◽

Binder Content ◽

Cemented Paste Backfill ◽

Compression Tests ◽

Isotropic Compression ◽

Initial Yield Stress ◽

Laboratory Test Results ◽

Cure Time ◽

Paste Backfill ◽

Compression Line

Abstract Deep and high-stress mining results in stress transfers onto the previously placed backfill, and mines have recorded several MPa induced backfill stress. Understanding the backfill-rock mass interaction is therefore critical. Previous work considered tabular ore bodies undergoing primarily one-dimensional compression and showed how the backfill reaction curves could be estimated from oedometer laboratory test results. This work considers massive orebodies and develops a similar approach based on isotropic compression curves. Isotropic compression tests exceeding 6 MPa are carried out on samples with 3.0–11.1% binder content, tested at 1-day cure time to 28-day cure time. The compression curve is characterized in three stages: initial elastic compression up to a yield point, followed by a transition stage to the start of a final stage with a linear post-yield compression line in \({\epsilon }_{v}-\text{l}\text{o}\text{g}\left({p}^{\text{'}}\right)\) space. Because these isotropic compression tests are rare (the reported results are the first for Cemented Paste Backfill), attempts are made to relate the isotropic compression test parameters to parameters from the more commonly used Unconfined Compression Strength (UCS) tests. Unifying equations as functions of binder content and cure time are found to determine the initial yield stress and the peak strength from UCS tests. These are then related to the corresponding parameters in isotropic compression. Finally, the slope of the post-yield compression line is found as a function of UCS, thereby enabling complete reconstruction of the isotropic compression response based on parameters from carefully controlled UCS tests, as functions of binder content and cure time. Although the calibrated parameters are specific to the studied mine’s materials, the framework is general and applicable to other mines’ CPBs.

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