Study on Limited Conditions and Calculation Formula of BQ Classification Based on Graphic Method

doi:10.12068/j.issn.1005-3026.2022.01.017

Abstract

Abstract: The calculation formula of BQ (basic quality) classification index in GB 50218—1994 is modified in the revised Standard for Engineering Classification of Rock Mass(GB/T 50218—2014)， but its two limiting conditions(saturated uniaxial compressive strength of rock and rock mass integrity coefficient)were not modified simultaneously. Through a large number of data studies， it is found that the calculation results are inconsistent with the qualitative and quantitative calculation results when the data are directly reduced by R_○c and K_○v constraints. Therefore， the limited conditions are modified and analyzed based on simplified graphical method. According to the analysis results that are widely affected by R_○c constraints， 54 sets of new data in the database are taken as samples， and a new calculation formula is established by regression analysis of the data reduced by R_○c constraints. The revised limit conditions and new section calculation formula obtained are analyzed and demonstrated on the basis of actual engineering data. The results show that the revised limited conditions and the calculation formula proposed in this study improve the agreement between the qualitative classification and the quantitative classification， and a more accurate classification result is obtained.

Key words: BQ (basic quality) classification; calculation formula; limited conditions; graphic method; piecewise function

CLC Number:

TU93

ZHAO Wen， JIN Chen， LU Bo， YANG Nan. Study on Limited Conditions and Calculation Formula of BQ Classification Based on Graphic Method[J]. Journal of Northeastern University(Natural Science), 2022, 43(1): 117-123.

References

[1]中华人民共和国住房和城乡建设部.国标《工程岩体分级标准》GB/T50218—2014［S］.北京:中国计划出版社，2015.(Ministry of Housing and Urban-Rural Development of the People’s Republic of China.Standard for engineering classification of rock mass(GB /T50218—2014)［S］.Beijing:China Planning Press，2015.
[2]Ootsuka Y，Ishikawa T，Tajima K，et al. Rock mass property evaluation based on the borehole wall images taken by using an ultrasonic scanner(USS)［J］.Journal of Nepal Geological Society，2018，55(1):1－6.
[3]Hou F J，Xie X K，Shi S S，et al. Dynamic optimization classification model for submarine tunnel surrounding rocks and its application in engineering［J］.Journal of Coastal Research，2019，94(sup1):311－315.
[4]Saroglou C，Qi S W，Guo S F，et al.ARMR:a new classification system for the rating of anisotropic rock masses ［J］.Bulletin of Engineering Geology and the Environment，2019，78(5):3611-3626.
[5]Chen Q F，Yin T C，Niu W J. Replacing RQD and discontinuity spacing with the modified blockiness index in the rock mass rating system［J］.Archives of Mining Sciences，2018，63(2):353-382.
[6]Wickham G E，Tiedemann H R，Skinner E H.Support determinations based on geologic predictions［J］.International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts，1975，12(7):95.
[7]Bieniawski Z T.Engineering rock mass classification—a complete manual for engineers and geologists in mining，civil and petroleum engineering［M］.Hoboken:Wiley，1989.
[8]Bieniawski Z T.Geomechanics classification of rock masses and its application in tunneling［J］.International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts，1975，12(10):141.
[9]Bieniawski Z T.Rock mass classification in rock engineering［C］//Proceedings of Symposium for Rock Engineering.Johannesburg:［s.n.］，1976:97-106.
[10]Khatik V M，Nandi A K.A generic method for rock mass classification ［J］.Journal of Rock Mechanics and Geotechnical Engineering，2018(10):102-116.
[11]Mohammad M，Mohammad F H. Modification of rock mass rating system:interbedding of strong and weak rock layers［J］.Journal of Rock Mechanics and Geotechnical Engineering，2017(9):1165-1170.
[12]Barton N.Some new Q-value correlations to assist in site characterization and tunnel design［J］.International Journal of Rock Mechanics and Mining Sciences， 2002，39(2):185-216.
[13]Barton N.Analysis of rock mass quality and support practice in tunneling and a guide for estimating support requirements［J］.Rock Mechanics，1974，6(4):189-236.
[14]Barton N.Rock mass classification and tunnel reinforcement selection using the Q-system［M］//Kirkaldie L.Rock Classification Systems for Engineering Purposes.West Conshohocken:ASTM International，1988:59-88.
[15]Chen L X，Chen S G，Tu P，et al.Study on mutual relationships between surrounding rock classifications by Q value，RMR and BQ method for underground cavern［J］.Subgrade Engineering，2017(6):107－112.
[16]林韵梅.岩体基本质量定量分级标准BQ公式的研究［J］.岩土工程学报，1999(4):481-485.(Lin Yun-mei.Study on BQ formula of basic quality grading standard of rock mass ［J］.Chinese Journal of Geotechnical Engineering，1999(4):481-485.)
[17]王小江.工程岩体基本质量指标和分级档次的研究［D］.沈阳:东北大学，2011.(Wang Xiao-jiang.Study on basic quality index and classification grade of engineering rock mass ［D］.Shenyang:Northeastern University，2011.)
[18]申艳军，徐光黎.国标岩体分级标准BQ的图解法表示［J］.岩石力学与工程学报，2012，31(sup2):3659-3665.(Shen Yan-jun，Xu Guang-li.Graphical representation of national rock mass classification standard BQ ［J］.Chinese Journal of Rock Mechanics and Engineering，2012，31(sup2):3659-3665.)
[19]陈曦，曾亚武，刘伟.岩体基本质量指标BQ图解法讨论［J］.铁道标准设计，2018，62(11):155-160.(Chen Xi，Zeng Ya-wu，Liu Wei.Discussion on graphic method of rock mass basic quality index BQ［J］.Railway Standard Design，2018，62(11):155-160.)
[20]周宗青，李术才，李利平，等.岩体质量等级分类预测方法及其工程应用［J］.中南大学学报(自然科学版)，2017，48(4):1049-1056.(Zhou Zong-qing，Li Shu-cai，Li Li-ping，et al.Classification method of rock mass quality and its engineering application ［J］.Journal of Central South University(Natural Science Edition)，2017，48(4):1049-1056.)
[21]Chen K D，Song Y H，Zhang Y L，et al.Modification of the BQ system based on the Lugeon value and RQD:a case study from the Maerdang hydropower station，China［J］.Bulletin of Engineering Geology and the Environment 2021，80(4):2979-2990.
[22]赖勇，张永兴.细观损伤理论确定岩体参数的方法研究［J］.岩石力学与工程学报，2008，27(sup1):2617-2623.(Lai Yong，Zhang Yong-xing.Analytical method of rock mass parameters with micromechanical damage theory［J］.Chinese Journal of Rock Mechanics and Engineering，2008，27(sup1):2617-2623.)(上接第116页)
[14]Andreou V，Dimopoulos G，Dermesonlouoglou E，et al.Application of pulsed electric fields to improve product yield and waste valorization in industrial tomato processing ［J］.Journal of Food Engineering，2020，270:109778.
[15]Zhao W，Yang R，Gu Y，et al.Effects of pulsed electric fields on cytomembrane lipids and intracellular nucleic acids of Saccharomyces cerevisiae ［J］.Food Control，2014，39:204-213.
[16]Wang M S，Wang L H，Bekhit A，et al.A review of sublethal effects of pulsed electric field on cells in food processing ［J］.Journal of Food Engineering，2018，223:32-41.
[17]Mota M J，Lopes R P，Koubaa M，et al.Fermentation at non-conventional conditions in food-and bio-sciences by the application of advanced processing technologies ［J］.Critical Reviews in Biotechnology，2018，38(1):122-140.
[18]Zhang C，Li L，Wang Y J，et al.Enhancement of the ANAMMOX bacteria activity and granule stability through pulsed electric field at a lower temperature((16±1) ℃)［J］.Bioresource Technology，2019，292:121960.
[19]Zhang H H，Zhao Z F，Chen S N，et al.Paracoccus versutus KS293 adaptation to aerobic and anaerobic denitrification:insights from nitrogen removal，functional gene abundance，and proteomic profiling analysis ［J］.Bioresource Technology，2018，260:321-328.
[20]Zhang H H，Li S L，Ma B，et al.Nitrate removal characteristics and ¹³C metabolic pathways of aerobic denitrifying bacterium Paracoccus denitrificans Z195 ［J］.Bioresource Technology，2020，307:123230.