A Loose Coupling Technique for Integrating GIS and Multi-Criteria Decision Making

Spatial decision making is characterized by problems associated with multiple and conflicting alternatives relating to geographical features and their attributes. As such, the search for the best possible alternative from a large set of such alternatives can be a daunting task. The aim of integrating GIS with Multi‐Criteria Decision Making (MCDM) is to develop a well‐defined process that can scan through such extensive fields of choice to arrive at the best possible solution. Goal Programming is one tool (developed in conjunction with MCDM) that can handle a problem with multiple, conflicting and incommensurable alternatives, and this article explains how the loose coupling technique can integrate MCDM with GIS to assist decision making among competing alternatives. As an example, this methodology has been applied for community development purposes in the Hooghly District of West Bengal, India.     

软弱围岩中偏压隧道的剪胀特性研究

在偏压情况下对不同埋深的4车道和2车道偏压公路隧道建立其力学模型,研究其松动围岩力学特征。在考虑应力剪胀对隧道围岩的影响后,计算出洞周围岩位移、收敛比。研究结果表明：对于相同的条件,4车道偏压公路隧道的围岩剪切破坏带比2车道更容易与地面贯通;随着剪胀角的递增,围岩位移矢量和隧道拱顶下沉量逐渐减小,拱脚水平位移逐渐增大;大跨度隧道围岩位移受剪胀角的影响比小断面隧道显著。     

“8.8”大地震后九寨沟世界遗产地湖泊淤积与沼泽化现状评价

地震及其伴生地貌过程破坏山体植被和土壤,产生的松散物源进入湖泊可能会带来泥沙淤积与沼泽化的风险.为探明九寨沟"8.8"大地震后湖泊淤积与沼泽化现状,以及松散物源的影响,本研究选取九寨沟景区内4个淤积与沼泽化程度不同的湖泊,进行了实地勘查,采用植被指标为主、促淤效应为辅的沼泽化综合评价方法进行现状评价;同时,结合无人机获取的湖泊周边环境和受灾程度信息,探讨了地震后伴生地貌过程及产物对九寨沟湖泊淤积与沼泽化的影响.结果表明：（1）四个湖泊的沼泽化发展模式均是由岸边向湖心推进.（2）各湖淤积与沼泽化程度空间分布特征存在差异,按发展程度从高到低依次表现为：五花海沼泽化程度最高,西北侧处于沼泽化后期（沼泽化指标值为[3,4]）;镜海次之,局部处于沼泽化盛期（沼泽化指标值为[1.5,3]）;犀牛海再次,仅出入水口处于沼泽化前期（沼泽化指标值为[1.5,2.5]）;箭竹海最低,整体处于沼泽化前期（沼泽化指标值为[0,1.5]）.（3）松散物源输入造成湖岸淤积程度增加、促进水生植被扩张,是造成九寨沟湖泊淤积和沼泽化发展的重要原因.管理者需重点关注小微湖泊、出入水口、受灾点的沼泽化发展情况.     

第四纪松散层大口径水井成井工艺

本文以吉林省某地供水井为例,总结了第四纪砾石松散层大口径水井钻探施工方法及成井工艺。根据地层特点按照钻孔设计施工,保证了成井质量。     

论小流域内泥石流物源的判别—以康定县子耳沟为例

小流域内松散碎屑物质的稳定性及储量可以作为泥石流沟判别的依据。本文以康定县子耳沟为例,通过对滑塌面积率、不良地质体长度比、流域内暴发泥石流的碎屑物量最低标准三个指数的计算,判定子耳沟流域内松散碎屑物质物源丰富且不稳定,泥石流暴发可能性大。这种方法的应用,可以指导泥石流的预报预警和防灾减灾工作,判别山区小流域暴发泥石流的易发程度及规模。     

浅层折射法在陕北侏罗纪煤田松散层调查中的应用及效果

陕北侏罗纪煤田榆神府处于鄂尔多斯地台东部,毛乌素沙漠东南缘。由于煤层埋藏浅．积沙厚,沙层含水量大,易于发生突水溃沙事故,给矿井安全生产带来较大威胁。陕西省煤田地质局物探测量队在石圪台矿井、活鸡兔矿井、大柳塔矿等矿区先后进行了以地震折射为主的勘探工作,不仅获得了各勘探区内基岩面、潜水面等松散层的地质信息,还掌握了其古河床、古冲沟的分布情况。在石圪台矿井勘探中,根据浅部1^-2煤层反射波对折射记录续至波的干涉情况,定性圈定区内1^-2的赋存范围。经钻孔验证,连续观测浅层折射法确定的潜水面深度、基岩面深度、风化层厚度等对综采有较大影响的主要界面绝对误差均小于10m,相对误差在3％左右。     

中深孔松动控制爆破在露天方解石矿中应用

桦甸市全兴矿业有限公司银龙大理岩矿是露天开采大理岩(方解石)的矿山,但由于传统的爆破方法造成优质矿石在爆破过程中因抛掷碰撞、炮孔内爆轰压力过大而形成粉碎区而使矿石粉碎,落地后被污染而使部分优质的矿石不能被利用,造成资源浪费。为此进行多次中深孔松动控制爆破试验并获得成功,使优质的矿石得到了回收,提高了产品质量,提高资源利用率,降低了生产成本。     

Simulating the effects of induced anisotropy on liquefaction potential using a new constitutive model

The effects of induced anisotropy on the undrained behaviour of very loose and saturated sands have been a subject of intensive investigation, both experimentally and theoretically, by several authors in the past few years. This paper proposes an original constitutive model well‐adapted to simulate the behaviour of sands subject to complex stress histories, in particular, the preloading cycle along the classical drained stress path in compression. The developed model belongs to the family of critical state models. Its construction is based on a few theoretical concepts taken from the theory of ‘Bounding Surface Plasticity’ developed among others by Y. Dafalias and Popov (1975), the ‘Clay And Sand Model’ (CASM) of H. Yu (2006), the CJS model (B. Cambou and K. Jafari (1988)) and the hyperelastic isotropic model of P. Lade (1987). To accurately simulate volume changes, which represent a key element in soil behaviour, a state‐dependent dilatancy rule is proposed, which can account for the influences of stress and void ratio. The current void ratio depends implicitly on the irreversible strains already accumulated hence the strain history. A kinematic hardening is combined with an isotropic hardening, involving rotation and distortion of the bounding surface, in order to capture correctly the experimental observations. Comparisons of experimental results to numerical simulations show that the model is able to simulate with a good precision the major trends of undrained responses of loose and presheared sands. It predicts correctly rapid static liquefaction at small or null drained preloading, as well as the progressive transition to a completely stable behaviour typical of dense sands, while the sample is loose in reality. At intermediate to large amplitudes of preloadings, the model also predicts correctly the temporary stage of instability when the deviatoric stress decreases slightly before rising up again. Copyright © 2013 John Wiley & Sons, Ltd.     

浅层气区地质岩心钻探技术综合研究与应用

核电发展需要稳定的铀资源供应,在我国北方油气盆地开展砂岩型铀矿战略选区和调查评价,需要对主要异常和重点地区进行取心钻探工程验证。但钻进地层极松散破碎,取心率低;浅层气发育,井控要求高;大直径扩孔,井斜和携岩困难;极寒冬季施工及环保要求高。通过研究和探索,形成了一套浅层气区极松散破碎地层的绿色综合钻探技术体系及工艺方法,包括单管锥阀取心、环保高粘低失水泥浆、远程井控、钻铤及导向钻具分级扩孔等,为北方砂岩型铀矿找矿突破和资源能源安全保障提供技术支撑,具有示范与推广作用。     

液压剪切式取样钻具的研究

在海洋和陆地水域等松软地层钻探取样过程中,使用常规取样钻具取样易造成样品质量差、取样率低等现象,为此特别设计一种液压剪切式取样工具。介绍了该钻具的设计原理、结构参数和试验效果。