Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect
The typical thick-hard limestone roof with high failure pressure and easy fracture closure under in situ stress is extremely prone to induce disasters, which seriously threatens the safe production of coal mines. The modification of carbonate minerals by acidic effects can effectively realize the we...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-08-01
|
| Series: | Minerals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-163X/13/8/1101 |
| _version_ | 1797583671922786304 |
|---|---|
| author | Mingxiao Hou Bingxiang Huang Xinglong Zhao Xuejie Jiao Xufei Jiang Zheng Sun |
| author_facet | Mingxiao Hou Bingxiang Huang Xinglong Zhao Xuejie Jiao Xufei Jiang Zheng Sun |
| author_sort | Mingxiao Hou |
| collection | DOAJ |
| description | The typical thick-hard limestone roof with high failure pressure and easy fracture closure under in situ stress is extremely prone to induce disasters, which seriously threatens the safe production of coal mines. The modification of carbonate minerals by acidic effects can effectively realize the weakening control of hard limestone strata. In this study, a multi-factor orthogonal experiment was designed for limestone acidification reactions, and the evaluation model for the reformation and strength weakening of hard limestone based on the acidic effect was established accordingly. The results showed that there is an order in the influence of various factors on the reaction parameters and strength indices of acidified limestone, and the improvement of rock properties by the level difference of acid concentration is significantly better than that of acid type and acidification time. Through numerical analysis, the evaluation model of limestone reformation and strength weakening considering the acid reaction parameters is given. The reliability of the model passed the credibility test and experimental verification, which can effectively reflect the strength response characteristics of acidified limestone. The simulated annealing (SA) algorithm is introduced to derive the optimal acidification system suitable for limestone weakening. Combined with the model, the control mechanism of the acidic effect on hard limestone strata was analyzed. The acidic effect can not only induce the rapid generation and expansion of micro-cracks at mineral-containing crystal defects, but also make the cracks remain relatively open under in situ stress due to the differential interaction on mineral components, which is conducive to the bearing capacity reduction and structural damage of limestone rock mass. The research results provide theoretical guidance for the acidification control of hard limestone strata in underground mines. |
| first_indexed | 2024-03-10T23:42:12Z |
| format | Article |
| id | doaj.art-111c3b1d6ed04cfdae6a769f094ca4bf |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-10T23:42:12Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Minerals |
| spelling | doaj.art-111c3b1d6ed04cfdae6a769f094ca4bf2023-11-19T02:21:50ZengMDPI AGMinerals2075-163X2023-08-01138110110.3390/min13081101Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic EffectMingxiao Hou0Bingxiang Huang1Xinglong Zhao2Xuejie Jiao3Xufei Jiang4Zheng Sun5State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, ChinaState Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, ChinaState Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, ChinaState Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, ChinaState Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, ChinaState Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, ChinaThe typical thick-hard limestone roof with high failure pressure and easy fracture closure under in situ stress is extremely prone to induce disasters, which seriously threatens the safe production of coal mines. The modification of carbonate minerals by acidic effects can effectively realize the weakening control of hard limestone strata. In this study, a multi-factor orthogonal experiment was designed for limestone acidification reactions, and the evaluation model for the reformation and strength weakening of hard limestone based on the acidic effect was established accordingly. The results showed that there is an order in the influence of various factors on the reaction parameters and strength indices of acidified limestone, and the improvement of rock properties by the level difference of acid concentration is significantly better than that of acid type and acidification time. Through numerical analysis, the evaluation model of limestone reformation and strength weakening considering the acid reaction parameters is given. The reliability of the model passed the credibility test and experimental verification, which can effectively reflect the strength response characteristics of acidified limestone. The simulated annealing (SA) algorithm is introduced to derive the optimal acidification system suitable for limestone weakening. Combined with the model, the control mechanism of the acidic effect on hard limestone strata was analyzed. The acidic effect can not only induce the rapid generation and expansion of micro-cracks at mineral-containing crystal defects, but also make the cracks remain relatively open under in situ stress due to the differential interaction on mineral components, which is conducive to the bearing capacity reduction and structural damage of limestone rock mass. The research results provide theoretical guidance for the acidification control of hard limestone strata in underground mines.https://www.mdpi.com/2075-163X/13/8/1101acidic effecthard stratumevaluation modelcrystal defectstrength weakening |
| spellingShingle | Mingxiao Hou Bingxiang Huang Xinglong Zhao Xuejie Jiao Xufei Jiang Zheng Sun Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect Minerals acidic effect hard stratum evaluation model crystal defect strength weakening |
| title | Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect |
| title_full | Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect |
| title_fullStr | Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect |
| title_full_unstemmed | Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect |
| title_short | Evaluation Model of Hard Limestone Reformation and Strength Weakening Based on Acidic Effect |
| title_sort | evaluation model of hard limestone reformation and strength weakening based on acidic effect |
| topic | acidic effect hard stratum evaluation model crystal defect strength weakening |
| url | https://www.mdpi.com/2075-163X/13/8/1101 |
| work_keys_str_mv | AT mingxiaohou evaluationmodelofhardlimestonereformationandstrengthweakeningbasedonacidiceffect AT bingxianghuang evaluationmodelofhardlimestonereformationandstrengthweakeningbasedonacidiceffect AT xinglongzhao evaluationmodelofhardlimestonereformationandstrengthweakeningbasedonacidiceffect AT xuejiejiao evaluationmodelofhardlimestonereformationandstrengthweakeningbasedonacidiceffect AT xufeijiang evaluationmodelofhardlimestonereformationandstrengthweakeningbasedonacidiceffect AT zhengsun evaluationmodelofhardlimestonereformationandstrengthweakeningbasedonacidiceffect |