GPS控制网在高标准农田建设中的布设研究

制订一套合理的GPS控制网实施方案对高标准农田建设具有重要意义。本文以贵州省安顺市西秀区的东屯乡、旧州镇和双堡镇为例,基于GPS相对定位原理以及GPS控制网的布设方案,介绍了GPS控制网在高标准农田建设中的实施应用。可为其他高标准农田建设提供参考,进一步提高工作效率、节约建设资金。     

近接隧道列车运行时地表振动响应数值模拟

鉴于目前城市地下铁路隧道平行、交叠的情况逐年增加,且对多列车耦合荷载作用下地表振动规律尚不清楚,本文建立了大直径盾构隧道下穿双线地铁隧道三维数值分析模型,并通过现有运行列车参数建立了刚体列车模型以及实体轨道模型。采用Hertz接触模拟了运动列车轮与钢轨的接触,通过罚接触与硬接触模拟了隧道与围岩的非线性接触,利用无限元人工边界模拟了无限半空间。使用时域显式整体分析方法模拟了编组列车在隧道内的运行并与实测地表振动加速度结果进行了对比,结果表明本文建立的数值模型能够较好地反映出真实地铁列车运行时地表的振动响应。在此基础上,分析了多线隧道交汇段不同列车运行工况下地表竖向加速度的时频特性以及分布规律。     

A prediction method of ground volume loss variation with depth induced by tunnel excavation

Acta Geotechnica - A new concept called the transmission ratio of ground volume loss (TRGVL) is proposed to describe the variation law of ground volume loss with depth above the tunnel. Based on...     

Effective skeleton stress and void ratio for constitutive modeling of fiber-reinforced sand

Acta Geotechnica - Inclusion of flexible fibers such as polypropylene and polyester is an effective method for soil improvement, as it significantly enhances the soil strength and ductility. A...     

层析静校正技术在烟台九目山岩体完整性评价中的应用

以国家石油战略储备地下水封洞库备选基地——烟台福山区九目山岩体完整性勘探评价项目为例,阐述了层析静校正技术的原理,比较了层析静校正和折射静校正的应用效果,认为复杂地表区折射波静校正方法效果一般,而走时层析静校正方法则能准确地反演地表速度模型,较好地解决复杂地表的静校正问题。利用层析反演建立的地表速度模型剖面,计算出岩体完整性分级剖面,结合层析静校正反射波剖面进行综合解释,有效地解决了工程勘探中的地质问题。     

再造青山——招远市玲珑矿田地质环境综合治理和土地复垦整理纪实

“矿区”这个词语,留给人的印象大多是：山体破坏,坑口遍野,植被占压,废尘纷扬,一幅满目苍夷的样子。然而,在山东省招远市玲珑矿田九曲蒋家栾家沟一带,却是另一幅景象：矿井林立,群山苍翠,一块块由复垦整理或由尾矿库复垦置换的良田,像一幅幅美丽的图画,给人留下无限的惊叹和遐想。这一切都得益于招远市国土资源局落实科学发展观,开展“再造青山”运动结下的累累硕果。     

西宁地区次生盐渍土的分布特征及地基处理方法

西宁地区次生盐渍土主要分布于山麓斜坡带高阶地和河谷高漫滩,前者属中～弱硫酸、亚硫酸盐渍土,且多具中等～强烈湿陷性,盐份主要来自斜坡后缘含盐碎屑岩风化物及易溶盐;后者为中等亚氯、亚硫酸盐渍土,溶于土中的盐份系浅层咸地下水常年毛细上升蒸发所致。其次生盐渍土的松胀性、溶陷性、腐蚀性较强,工程建设要引起重视。     

Mapping deep targets based on integrated 3D MT-gravity interpretation: a case study

Mapping deep geological hydrocarbon targets is of significant importance in basin exploration. In areas lacking reliable seismic data, magnetotelluric (MT) and gravity explorations are helpful to delineate the distribution of potential deep geological hydrocarbon targets. Here we investigate the effectiveness of the integrated 3D MT and gravity explorations for mapping the potential deep hydrocarbon source rocks. The result based on the data from the W Basin (part of the Ordes Basin) of China demonstrates that the method is efficient and economical for basin exploration. The method is particularly useful in target areas which are of great interest for oil and gas exploration but lack high quality seismic data. In our method, we first use the high-precision 3D small-bin MT data acquisition to improve the data accuracy. Then we perform datum static correction method and apply 3D inversion to obtain the3D resistivity distribution. We also develop a layered resistivity model based on resistivity logging to assist the interpretation of the inverted 3D resistivity data so as to derive an initial 3D geological model. Starting from the initial model, we use 2D gravity data to update the model via 2D inversion line by line, and then pass the updated model for the next round of the 3D MT inversion. The integrated inversion is implemented iteratively so the model converges to satisfy the need of final geological analysis. The application to the W Basin shows that we could successfully delineate the geological distribution of the potential deep hydrocarbon source rocks within the basin and map the thickness of the upper Paleozoic.     

矿山灾害电阻率法预测机理及试验

岩爆和煤层突出灾害对煤矿的安全生产及生产效率有着十分严重的影响。本文讨论了电阻率法在矿山灾害预报中的应用,利用试验观测了岩样在破坏过程中电阻率的变化,其结果表明,岩石电阻率在其破坏过程中变化明显,说明电阻率法可以用于矿山灾害的预测、预报