开口管桩竖向承载力时间效应研究

时间效应是指管桩沉桩后承载力随休止时间的提高。统计分析发现单桩承载力每时间对数的增长范围为15%～29%。桩基承载力的增长源于桩侧土的固结、触变恢复、老化以及蠕变和土壳效应,基于此提出管桩承载力时间效应3阶段理论模型,并建立基于固结理论的开口管桩承载力时效解析计算模型。计算表明,摩擦型开口管桩承载力随时间的相对增长速度随土塞率近似呈线性增长;完全非闭塞的摩擦型开口管桩承载力的相对增长速度高出闭口桩约10%。     

水合物藏的类型、特点及开发方法探讨

天然气水合物作为潜能巨大、资源量丰富、燃烧值高的未来新能源,但由于其特殊的物理力学性质和赋存状态,经济开采技术仍面临诸多难题.本文以全球勘探发现存在天然气水合物的地区为基础,介绍了全球主要水合物的海陆资源分布及开采难易程度;以主要影响天然气水合物开采方式选择因素为基础,分析了天然气水合物在地层中的赋存类型、成藏模式和储...     

连通域标识法在FMI图像溶洞信息定量拾取中的应用

溶蚀孔洞在碳酸盐岩储层中是重要的流体储集空间,研究成像测井(FMI)图像孔洞连通域标记及信息定量拾取很有意义.全井眼微电阻率成像测井(FMI)经数据处理后可得到全井壁高分辨率的彩色图像,经图像灰度化、中值滤波处理后,通过阈值分割得到能够反映井壁溶蚀孔洞特征的二值图像,孔洞表现为黑色暗斑.基于等价对处理的图像连通域标记算法具有快速、不重复标记的优点,利用该算法,可准确地从二值图像中标记溶蚀孔洞连通域,进而可对每个连通域进行目标信息拾取,包括孔洞尺寸、连通域面积、圆度等.利用反映溶蚀孔洞发育程度的面孔率曲线对图像进行分层,在此基础上可拾取每一层段溶蚀孔洞面孔率、分选系数及溶洞密度值的分布等非均质信息,能够定量地评价溶蚀孔洞发育、非均质性强的碳酸盐岩储层,也是FMI图像应用于岩石孔洞结构信息定量表征新的尝试.     

前兆台网服务器更换升级的典型问题分析

前兆台网服务器是前兆台网技术系统的核心设备,所以服务器的安装配置显得尤为重要,特别是在更换服务器后如何能更快更完整地完成整套系统的安装配置更是系统维护人员都要面临的问题。对在更换升级过程中遇到的问题进行了详细分析,解决了很多困扰系统维护人员的实际问题。     

青海南部蛇绿岩中辉长岩锆石SHRIMP U-Pb定年和岩石地球化学特征

青海南部蛇绿岩呈构造岩片产于晚三叠世浅变质细碎屑岩中.扎河地区出露的辉长岩为蛇绿岩的组成单元,属低钾拉斑系列,其锆石SHRIMP U-Pb年龄为(239.8±3.1)Ma,表明岩石形成于中三叠世早期.地球化学特征上,岩石富MgO、Al2O3,低K2O、TiO2;REE总量低,(La/Yb)N=1.10～4.40,LREE略显富集,δEu=1.50～2.41,具有明显正铕异常;大离子亲石元素(Rb、Ba、Sr、Th、U)富集、高场强元素(Nb、Zr、Ti)亏损,反映岩浆源区曾遭受到俯冲组分的影响.综合分析认为,扎河辉长岩岩石具有板内和弧岩浆岩的双重属性,其形成环境为弧后盆地,表明中三叠世早期巴颜喀拉盆地发生过一次拉张事件.在区域上,它是甘孜-理塘蛇绿岩的组成部分.     

库岸塌岸防治工程施工监理实践

湖北省三峡库区兴山县高阳镇库岸塌岸防治工程是三峡库区地质灾害首批治理的重点．在实施过程中实行专业监理,有效地控制了工程质量、进度、投资,受到了国务院三峡库区地质灾害防治工作领导小组专家组的好评。本文结合防治工程特点对工程监理组织机构、监理工作内容等进行了有益的探索和实践。     

Imaging-Based Characterization of Perthite in the Upper Triassic Yanchang Formation Tight Sandstone of the Ordos Basin,China

This work investigated the element distribution of perthite from the Upper Triassic Yanchang Formation tight sandstone in the Ordos Basin of northern China by field emission scanning electron microscopy(FE-SEM) and energy dispersive spectrometer(EDS). FE-SEM results indicate significant differences in the morphology of Na-rich feldspar when K-rich feldspar is the main component of the perthite. EDS results show that different types of perthite have clearly defined differences on different element indexes. Additionally, indexes such as average-weight-K(K-rich)/Na(Na-rich), maximumweight-K(Na-rich)/Na(Na-rich) and average-atomic-K(K-rich)/Na(Na-rich) might be the most effective ones to identify perthite types. Perthite is divided into six main types, i.e., perthite with thick parallel stripe distribution, with thin parallel stripe distribution, with lumpy stripe distribution, with dendritic stripe distribution, with encircling stripe distribution, and with mixed stripe distribution.     

Responses of Soil CO2, CH4 and N2O Fluxes to N,P, and Acid Additions in Mixed Forest in Subtropical China

Understanding how nitrogen (N) availability interacts with soil acidity and phosphorus (P) availability to affect soil-atmosphere exchanges in CO₂, CH₄ and N₂O in forest ecosystems is important for understanding the mechanisms driving ecosystem responses to enhanced N deposition. Here, we conducted an experiment with N, P and acid (H) addition in a mixed forest in subtropical China to investigate how acid and P addition affects CO₂, CH₄ and N₂O exchange under N addition. Our results showed that soil NH₄⁺-N and NO₃^--N increased after N addition, but CO₂ emissions in N addition plots remained unaffected. CH₄ uptake in N-, P-, NP-, NH- and NPH-addition plots were reduced by 21.1%, 15.7%, 39.1%, 26.6%, and 28.4%, respectively. CH₄ uptake in NP-addition plots were lower compared to N-addition and P-addition plots, indicating that N and P addition had an additive effect on inhibiting CH₄ uptake. N₂O emission in N-, NP-, NH- and NPH-addition plots increased by 158.6%, 176.0%, 117.2%, and 91.8%, respectively. N₂O emissions in NPH-addition plots were lower compared to NP-addition plots while showed no difference between N-addition and NH-addition plots. This suggests that only under P rich conditions, acid addition would greatly mitigate N₂O emissions under N addition. Our results demonstrate that for N and P co-limited forest ecosystems with acidic soils, low P availability constrains the inhibition of soil CH₄ uptake by N deposition. When P availability is low, a weak soil acidation induced by N deposition may have less influence on the stimulation of N₂O emissions by N deposition.     

地下开采引起围岩间断面变形特征的软材料小模型研究

为了研究地下开采引起围岩变形和断层活化现象,文章采用一种软材料的小模型进行地下开采间断面变形的模拟。模型中通过模拟一个矩形地下采区上方围岩的变形来研究一个水平间断面发生活化后的弯曲现象。模拟结果表明,间断面上的剪切位移分布具有"双峰"的特征或规律。这种分布特征或规律,得到了数值模拟结果的验证。同时,也证明了该方法的有效性。该方法最大的优点是,可以用小尺寸模型有效模拟在自重体积力作用下开挖引起的围岩变形现象,具有实验装置简单、实验用时短、操作方便、实验成本低等诸多优点,是一种值得推广的物理模拟方法。      

First Discovery of Gold Ore Bodies in the Lieryu Formation of the Liaohe Group in the Liaodong Area, China

<正>Objective Numerous large deposits of lead–zinc,gold,boron,magnesite,and talc are distributed throughout the Liaodong area,within different layers of the Paleoproterozoic Liaohe Group.The Liaohe Group comprises five formations as follows(from bottom to top).The Langzishan Formation consists of volcaniclastic rocks