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Limit analysis of supporting pressure in tunnels with regard to surface settlement

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Journal of Central South University 2015年第1期22卷 303-309页

作者：杨小礼覃长兵 School of Civil Engineering Central South University College of Civil Engineering Fujian University of Technology

The proliferation of Hoek-Brown nonlinear failure criterion and upper bound theorem makes it possible to evaluate the stability of circular tunnels with an original curved collapsing mechanism. The arch effect of shallow circle tunnel is not taken into consideration so that the mechanical characteristics can be easily described. Based on the mechanism, the upper bound solution of supporting pressure of tunnels under the condition of surface settlements and overloads on the ground surface is derived. The objective function is formed from virtual work equations under the variational principle, and solutions are presented by the optimum theory. Comparisons with previous works are made. The numerical results of the present method show great agreement with those of existing ones. With regard to the surface settlement and overloads, the influence of different rock parameters on the collapsing shape is analyzed.

关键词： circular tunnel Hoek-Brown criterion collapse mechanism surface settlement

Stability analysis for natural slope by kinematical approach

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Journal of Central South University 2014年第4期21卷 1546-1553页

作者：孙志彬覃长兵 School of Civil Engineering Central South University

The stability of natural slope was analyzed on the basis of limit analysis. The sliding model of a kind of natural slope was presented. A new kinematically admissible velocity field for the new sliding model was constructed. The stability factor formulation by the upper bound theorem leads to a classical nonlinear programming problem, when the external work rate and internal energy dissipation were solved, and the constraint condition of the programming problem was given. The upper bound optimization problem can be solved efficiently by applying a nonlinear SQP algorithm, and stability factor was obtained, which agrees well with previous achievements.

关键词： natural slope stability analysis limit analysis upper bound theorem

Kinematic analysis of geosynthetics-reinforced steep slopes with curved sloping surfaces and under earthquake regions

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Journal of Central South University 2019年第7期26卷 1755-1768页

作者： ZHOU Jian-feng qin chang-bing PAN Qiu-jing WANG Cheng-yang College of Civil Engineering Huaqiao University Xiamen 361021 China Department of Civil & Environmental Engineering National University of Singapore Singapore 117576 Singapore School of Civil Engineering Central South University Changsha 410075 China

A procedure of kinematic analysis is presented in this study to assess the reinforcement force of geosynthetics required under seismic loadings, particularly for steep slopes which are hardly able to maintain its stability. Note that curved sloping surfaces widely exist in natural slopes, but existing literatures were mainly focusing on a planar surface in theoretical derivation, due to complicated calculations. Moreover, the non-uniform soil properties cannot be accounted for in conventional upper bound analysis. Pseudo-dynamic approach is used to represent horizontal and vertical accelerations which vary with time and space. In an effort to resolve the above problems, the discretization technique is developed to generate a discretized failure mechanism, decomposing the whole failure block into various components. An elementary analysis permits calculations of rates of work done by external and internal forces. Finally, the upper bound solution of the required reinforcement force is formulated based on the work rate-based balance equation. A parametric study is carried out to give insights on the implication of influential factors on the performance of geosynthetic-reinforced steep slopes.

关键词： earthquakes pseudo-dynamic approach discretization-based kinematic analysis geosynthetics steep slopes

^1H NMR谱中质子的化学等价性和磁等价性问题探讨

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化学教育 2016年第6期37卷 71-74页

作者：秦丙昌安阳师范学院化学化工学院

对1H NMR谱中质子的化学等价性和磁等价性问题进行了探讨,介绍了其意义和比较简便的判断方法,通过实例指出了该部分内容教学中容易忽视的一些问题。

关键词： 1H NMR谱化学等价磁等价

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山区铁路列车运缓问题分析及对策措施

铁道运输与经济 2005年第3期27卷 39-41页

作者：覃长炳石俊贵阳铁路分局办公室贵州贵阳550003

从社会和自然因素、管理因素、设备故障因素等方面,分析了山区铁路列车运缓的原因,提出解决山区铁路列车运缓问题应采取修建正规的人畜通道、改平交道口为立交、对灾害进行重点预防和加强行车及线路大中修管理等措施。

关键词：山区铁路列车立交行车中修修建线路道口预防原因

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醋氯芬酸的合成

中国医药工业杂志 2008年第6期39卷 408-409页

作者：秦丙昌陈静张有娟安阳师范学院化学化工学院河南安阳455000

醋氯芬酸（aceclofenac，1），化学名为2-（2，6-二氯苯胺基）苯乙酰氧基乙酸，由西班牙Almirall-Prodesfarma制药公司研发，1992年首先在西班牙上市，1998年收入欧洲药典和英国药典。本品是口服强效非甾体抗炎药，适用于治疗各种风湿... 详细信息

醋氯芬酸（aceclofenac，1），化学名为2-（2，6-二氯苯胺基）苯乙酰氧基乙酸，由西班牙Almirall-Prodesfarma制药公司研发，1992年首先在西班牙上市，1998年收入欧洲药典和英国药典。本品是口服强效非甾体抗炎药，适用于治疗各种风湿性关节炎、类风湿性关节炎、骨关节炎和脊椎炎，也适用于各种疾病引起的疼痛和发热，是治疗急慢性疼痛、抗炎的安全可靠的药物。

关键词：二氯苯类风湿性关节炎非甾体抗炎药合成醋乙酰氧基制药公司骨关节炎

地震边坡稳定性有限元塑性极限分析拟动力法研究

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Journal of Central South University 2023年第7期30卷 2374-2391页

作者：周建烽郑子玉鲍挺涂兵雄俞剑覃长兵 College of Civil Engineering Huaqiao UniversityXiamen 361021China School of Civil Engineering Chongqing UniversityChongqing 400045China School of Civil Engineering Tongji UniversityShanghai 200092China Chongqing Field Scientific Observation Station for Landslide Hazards in Three Gorges Reservoir Area Chongqing 400045China

地震诱发边坡失稳是地震灾害的主要类型之一,开展地震作用下边坡稳定性研究具有重要意义。常规拟静力法无法准确模拟地震波在边坡土体中传播的时间和空间效应,难以真实反映地震荷载。本文采用拟动力法模拟地震动荷载输入,基于塑性极限... 详细信息

地震诱发边坡失稳是地震灾害的主要类型之一,开展地震作用下边坡稳定性研究具有重要意义。常规拟静力法无法准确模拟地震波在边坡土体中传播的时间和空间效应,难以真实反映地震荷载。本文采用拟动力法模拟地震动荷载输入,基于塑性极限分析下限定理,结合有限元离散技术,建立了满足静力平衡条件、屈服条件、应力边界条件和间断条件的地震边坡稳定性有限元极限分析下限法数学规划模型,基于内点算法寻求边坡超载系数和安全系数的下限解。通过对典型边坡算例分析,验证了本文方法的正确性。进一步分析了均质土边坡、抗剪强度参数随深度线性增加的非均质土边坡以及双层土边坡的地震稳定性,讨论了关联和非关联流动准则对地震边坡稳定性的影响。结果表明:拟静力法和非关联流动法则会低估地震边坡稳定性;边坡安全系数有限元极限分析下限解与上限解之间的差异小于4.5%,本文方法计算结果接近地震边坡稳定性真解。

关键词：地震边坡稳定性有限元极限分析拟动力法真解

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N-丁基-1-脱氧野尻霉素的合成新方法

合成化学 2014年第1期22卷 117-120页

作者：秦丙昌高艳萍李刚安阳师范学院化学化工学院河南安阳455000

以2,3,4,6-四-O-苄基-α-D-葡萄糖为原料,经4步反应制得中间体2,3,4,6-四-O-苄基-D-葡萄糖酸-δ-内酰胺(6);在碱性条件下6与正溴丁烷进行氮原子上的烃基化反应得N-丁基-2,3,4,6-四-O-苄基-D-葡萄糖酸-δ-内酰胺(7);用氢化铝锂将7的羰基... 详细信息

以2,3,4,6-四-O-苄基-α-D-葡萄糖为原料,经4步反应制得中间体2,3,4,6-四-O-苄基-D-葡萄糖酸-δ-内酰胺(6);在碱性条件下6与正溴丁烷进行氮原子上的烃基化反应得N-丁基-2,3,4,6-四-O-苄基-D-葡萄糖酸-δ-内酰胺(7);用氢化铝锂将7的羰基还原为亚甲基得N-丁基-2,3,4,6-四-O-苄基-1-脱氧野尻霉素(8);8经催化氢解脱去苄基合成了N-丁基-1-脱氧野尻霉素,其结构经1H NMR,13C NMR和MS确证。

关键词： 2,3,4,6-四-O-苄基-α-D-葡萄糖 N-丁基-1-脱氧野尻霉素米格鲁特氮杂糖合成

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二醇及氨基醇类鬼臼毒素衍生物的合成

有机化学 1998年第1期18卷 43-49页

作者：秦丙昌陈宁吴安心田元潘鑫复兰州大学化学系应用有机化学国家重点实验室兰州730000 河南省安阳师专化学系

以天然产物鬼臼毒素(1)为原料,合成了四种二醇及氨基醇类鬼臼毒素衍生物:4-O-乙基表鬼臼苦醇(4),(1R,2S,3R,4S)-1-3’,4’,5’-三甲氧基苯基-2-氨甲基-3-羟甲基-4-乙氧基-6,7-亚甲二氧基-1,2,3,4-四氢萘(5),(1R,2S,3R,4S)-1-3’,4’,5’-三甲氧基苯基-3-羟甲基-2-氨基-4-乙氧基-6,7-亚甲二氧基-1,2,3,4-四氢萘(6)和4-O-异丙基表鬼臼苦醇(7)。4～7及中间产物8～11都是新化合物。

关键词：二醇氨基醇合成鬼臼毒素衍生物手性配体