基于ARCGIS的矿山开采沉陷灾害预警系统

为了实现与环境协调的矿产资源开采,提出建立并开发了矿山开采沉陷灾害预警系统。以美国大型软件ARCGIS为开发平台,采用ARCMap Object开发方法开发了矿山开采沉陷灾害预警系统;建立了该系统计算参数的位移反分析模型,引入单纯形优化方法,编制了系统计算参数的位移反分析模块;进行了实例计算分析。第1个实例分析了某工作面开采引起的地表沉陷灾害,并与CXYJ2001的计算结果对比,验证了系统的计算可靠性,并展示了系统的功能。第2个实例是对江苏姚桥煤矿开采方案引起的地表沉陷灾害预警分析,优化了开采方案。研究表明,系统是实现与环境协调的矿产资源开采的重要辅助手段。最后,介绍了进一步工作的方向。     

开滦东欢坨矿北二采区冒裂带高度可视化数值模拟

针对东欢坨矿区开采煤8、煤9诱发的顶板涌(突)水问题,在分析研究区内水文地质、工程地质条件的基础上,综合考虑了冒裂带发育高度的各种影响因素,确立了研究区的评价模型,并根据采面规格和开采方法设计了6种模拟方案。采用世界上先进的数值模拟评价的FLAC3D专业软件包,对开采煤8、煤9顶板冒裂带发育高度进行了可视化数值仿真模拟分析,计算出6种方案的冒裂带高度。      

上海市第四承压含水层变形特征研究

上海市自1968年调整开采层次以后,第四承压含水层逐渐成为地下水主要开采层次,历史上曾因过度开采利用地下水而成为主要的压缩土层。本文依据上海市长期的地下水位和地面沉降监测资料,总结了第四承压含水层在不同水位变化条件下的变形特征,同时根据压缩试验资料,对第四承压含水层变形机理探讨,为合理开发利用地下水资源提供理论依据。     

潘二矿下向卸压开采高应力演化特征试验研究

为研究深部近距离煤层群下向卸压开采高应力演化的特征,根据潘二煤矿深部近距离煤层群8煤和6煤地质与开采技术条件,设计了下向卸压开采的二维相似材料模拟试验模型,对8煤和6煤开采引起的采动应力进行监测。系统分析了8煤下向开采与6煤开采后的采场围岩采动应力、岩层运移及不规则煤柱对采动应力演化的影响,获得了近距离煤层群8煤下向卸压开采的顶底板采动高应力演化特征及6煤回采期间覆岩运移、采动应力裂隙演化和来压特征,得出了下向卸压开采不规则煤柱对采动应力、裂隙分布的影响规律。研究不仅为以采动高应力演化为主导作用的煤岩动力灾害防治提供了理论基础,也为卸压开采采场参数设计与优化提供了技术支撑。     

开采引起上覆公路地表沉降与变形的数值分析

由于开采的需要,某矿群已从露天转入地下开采,在其开采境界内上部有一条乡镇公路穿过,为最大限度地回收资源和保证上部公路的安全运行,通过岩体宏观结构调查分析、取样、室内岩石力学试验和工程类比,综合确定岩体力学参数;并采用三维有限元对三种不同的开采方案引起公路地表的沉降高度进行了卸荷模拟和数值计算,模拟计算结果表明：随着开采高度的增加,公路地表沉降高度呈非线性增加,开采高度越高,其地表沉降高度越大,开采高度采超过1 300水平时,上部围岩将处于不稳定状态,影响公路的安全运行。通过工业试验,开采高度定为1 300水平时,其沉降高度在15 cm以内,能够保证上覆公路的安全运行。     

数值法模拟赵油坊水源地深层地下水允许开采量

通过抽水试验,确定了拟建水源地——赵油坊的水文地质参数:平均导水系数878.27m2/d,弹性释水系数为6.85×10-4,压力传导系数为1.55×106m2/d,水跃值为3.44m;根据水文地质参数把水源地划分为6个单元。选用合理的计算模型,模拟不同开采条件下地下水水位下降情况,确定以24000m3/d的开采方案较为合理。      

埋藏型岩溶地下水源地的三维数值模拟——以天津市宁河北岩溶地下水源地为例

根据宁河北岩溶地下水源地已有的水文地质勘查成果和大型抽水试验资料,对研究区水文地质条件进行概化,建立地下水流三维非稳定流数学模型并进行数值计算,对开采性抽水试验的地下水位变化过程进行模拟。结果表明,该模型可以刻画埋藏型水源地地下水流场的变化过程,用它对规划的水源地三种开采方案的开采动态进行预测计算也取得了良好的效果。模拟计算中将开采条件下浅层第四系含水层对深层奥陶系灰岩含水层的越流补给处理为边界条件,可以刻画埋藏型水源地在开采条件下获得的补给增量。      

开滦东欢索矿北二采区冒裂带高度可视化数值模拟

针对东欢索矿区开采煤8、煤9诱发的顶板涌（突）水问题，在分析研究区内水文地质、工程地质条件的基础上，综合考虑了冒裂带发育高度的各种影响因素，确立了研究区的评价模型，并根据采面规格和开采方法设计了6种模拟方案。采用世界上先进的数值模拟评价的FLAC^3D专业软件包，对开采煤8、煤9顶板冒裂带发育高度进行了可视化数值仿真模拟分析，计算出6种方案的冒裂带高度。     

苏北沿海三市三维地下水流数值模拟

20世纪80年代以来,苏北沿海三市（连云港、盐城和南通）地下水过量开采导致部分地区水位持续大幅下降,引发地面沉降、水质咸化等问题。本文基于研究区大量地质、水文地质资料,以及2005—2013年地下水开采和水位观测数据,经过模型识别、验证,建立了能刻画苏北沿海三市地下水流场演化的三维非均质各向异性地下水流数值模型,模拟了研究区2005—2013年开采量由约2.03亿m³逐渐减少到1.56亿m³条件下深部地下水系统流场（包括第Ⅱ、Ⅲ、Ⅳ承压含水层）的动态演化过程。结果表明,各观测孔的水位实测值与模拟值吻合良好,水位及水均衡模拟结果显示各含水层水位下降得到有效控制,但是该区域地下水仍处于超采状态。为进一步控制水位下降,防治咸水扩散、地面沉降等地质环境灾害,模型预测并比较了现状开采和限制开采2种不同开采方案下2014—2020年苏北沿海三市深层地下水流场的变化趋势。预报结果显示,2种开采方案下,各含水层水位下降速率均减小,尤其是限制开采方案下,第Ⅱ、Ⅲ和Ⅳ承压含水层的区域水位平均下降速率依次为0.15、0.16和0.15 m/a,分别比模拟期减小了46.43%、65.21%和48.28%,在开采强度降至最低的条件下储存量变化速率仍为负值,说明需要进一步加强地下水限制开采的力度。     

干扰系数计算在开采井群优化布设中的应用

干扰系数表征了开采井受干扰的程度,其除受含水层性质、补给、排泄条件等天然因素影响外,还与井的结构和数量、井间距以及在平面上的布置等人为因素有关,因为试验复杂、成本高,一般多在水源地的勘探和开采阶段通过抽水试验求得。本文以甘肃省张掖电厂黑河滩水源地“探采结合”勘探实例,在单孔、干扰和群孔开采性抽水试验的基础上,准确计算干扰系数等水文地质参数,提出技术经济合理的开采方案,并通过探采生产井的优化布置,达到单井及井群出水量大、出水稳定、井间距小、井间干扰小,易于水源地管理保护和节约建设投资的目的。     

The effect of the large-scale mantle flow field on the Iceland hotspot track

Fluid dynamical simulations were carried out in order to investigate the effect of the large-scale mantle flow field and the depth of the plume source on the structure of the Iceland plume through time. The time-dependent location and shape of the plume in the Earth's mantle was calculated in a global model and it was refined in the upper mantle using a 3D Cartesian model box. Global flow was computed based on density heterogeneities derived from seismic tomography. Plate motion history served as a velocity boundary condition in both models. Hotspot tracks of the plume conduits and the plume head were calculated and compared to actual bathymetry of the North Atlantic. If a plume source in the lowermost mantle is assumed, the calculated surface position of the plume conduit has a southward component of motion due to southward flow in the lower mantle. Depending on tomography model, assumed plume age and buoyancy the southward component is more or less dominating. Plume models having a source at the 660 km discontinuity are only influenced by flow in the upper mantle and transition zone and hence rather yield westward hotspot motion. Many whole-mantle plume models result in a V-shaped track, which does not match the straight Greenland–Iceland–Faroe ridge. Models without strong southward motion, such as for a plume source at 660 km depth, match actual bathymetry better. Plume tracks were calculated from both plume conduits and plume heads. A plume head of 120 K anomalous temperature gives the best match between plume head track and bathymetry.     

Groundwater flow modeling of Quaternary aquifer Ras Sudr,Egypt

Recently, Ras Sudr (the delta of Wadi Sudr) area received a great amount of attention due to different development expansion activities directed towards this area. Although Quaternary aquifer is the most prospective aquifer in Ras Sudr area, it has not yet completely evaluated. The present work deals with the simulation of the Quaternary groundwater system using a three-dimensional groundwater flow model. MODFLOW code was applied for designing the model of the Ras Sudr area. This is to recognize the groundwater potential as well as exploitation plan of the most prospective aquifer in the area. The objectives were to determine the hydraulic parameters of the Quaternary aquifer, to estimate the recharge amount to the aquifer, and to determine the hydrochemistry of groundwater in the aquifer. During this work, available data has been collected and some field investigation has been carried out. Groundwater flow model has been simulated using pilot points’ method. SEAWAT has been also applied to simulate the variable-density flow and sea water intrusion from the west. It can be concluded that: (1) the direction of groundwater flow is from the east to the west, (2) the aquifer system attains a small range of log-transformed hydraulic conductivity. It ranges between 3.05 and 3.35 m/day, (3) groundwater would be exploited by about 6.4 × 10⁶ m³/year, (4) the estimated recharge accounts for 3 × 10⁶ m³/year, (5) an estimated subsurface flow from the east accounts for 2.7 × 10⁶ m³/year, (6) the increase of total dissolved solids (TDS) most likely due to dilution of salts along the movement way of groundwater from recharge area to discharge area in addition to a contribution of sea water intrusion from the west. Moreover, it is worth to note that a part of TDS increase might be through up coning from underlying more saline Miocene sediments. It is recommended that: (1) any plan for increasing groundwater abstraction is unaffordable, (2) reliable estimates of groundwater abstraction should be done and (3) automatic well control system should be made.     

千岛湖配水工程对钱塘江河口盐水入侵影响

杭州市第二水源千岛湖配水工程（简称配水工程）的实施将引起富春江水库下泄流量及过程改变,从而对钱塘江河口盐水入侵产生影响。建立考虑涌潮作用的二维盐度数值模型,在验证钱塘江河口潮位和盐度的基础上,预测配水工程实施对河口盐水入侵距离和重要取水口含氯度超标时间的影响。研究表明:配水工程实施后,上游富春江水库若按现状调度方案,对枯水年影响大,咸水上溯距离增加3.7 km,沿岸取水口的可取水时间缩短0.2~3.6 d,丰、平水年盐水入侵和引水前相当;通过水库的优化调度,可基本消除枯水年引水造成的盐水入侵影响。为减少配水工程实施的盐水入侵影响,采用水库的优化调度模式是必要的。     

Hydrodynamic model of cells for designing systems of urban groundwater drainage

An improved mathematical hydrodynamic quasi-two-dimensional model of cells, CELSUB3, is presented for simulating drainage systems that consist of pumping well fields or subsurface drains. The CELSUB3 model is composed of an assemblage of algorithms that have been developed and tested previously and that simulate saturated flow in porous media, closed conduit flow, and flow through pumping stations. A new type of link between aquifer cells and drainage conduits is proposed. This link is verified in simple problems with well known analytical solutions. The correlation between results from analytical and mathematical solutions was considered satisfactory in all cases. To simulate more complex situations, the new proposed version, CELSUB3, was applied in a project designed to control the water-table level within a sewer system in Cha?ar Ladeado Town, Santa Fe Province, Argentina. Alternative drainage designs, which were evaluated under conditions of dynamic recharge caused by rainfall in a critical year (wettest year for the period of record) and a typical year, are briefly described. After analyzing ten alternative designs, the best technical–economic solution is a subsurface drainage system of closed conduits with pumping stations and evacuation channels. Electronic Publication     

Optimization of the Garzan Hydropower System operations

Through the rapid development of the watersheds in Turkey with projects developed by incorporated companies, a problem has arisen of how to operate a cascade reservoir system composed of state- and private sector-owned reservoirs in terms of the volume and timing of water releases to meet downstream water demands. This study presents a catchment-based optimization model based on inflow forecast with frequent updating for the integrated operation of hydropower plants under various sales methods. The model is formulated in terms of nonlinear programming (NLP) on a monthly basis for a 1-year period to assess the production strategies of the system reservoirs for that year. This model provides the basic constraints on the reservoir volume for daily and hourly optimization procedures. Forecasted flows are generated using seasonal autoregressive integrated moving average (ARIMA) models based on historical flow values. The proposed model is tested on the Garzan Hydropower System using historical, mean, and forecasted flow values. The results show that the integrated operation plan and improvement in the accuracy of inflow forecasts yield economic benefits as a consequence of optimal reservoir operation.     

疏勒河昌马堡站年径流长期预报模型研究

通过分析疏勒河昌马堡站年径流变化规律,并将年径流系列按照频率25%及75%为界,划分成3种情况：即多水年Xi〉35.0,中水年24.5≤Xi≤35.0,小水年Xi〈24.5。计算其状态转移概率得出：年径流过程从某一状态转移至其他状态的可能性都有,但其转移概率的最大值达66.7%。由此可知,年径流的变化过程不仅有随机性,而且有很强的相依性。通过多年对站年径流预报工作的实践,经过各种方法的比较检验,认为建立年平均流量的时间序列组合模型,其逐年预报的精度较高,经过误差评定分析,该模型均为甲级方案,检验预报时性能较稳定,能对昌马堡站年平均流量进行有效预报,为疏勒河流域调水提供技术支撑。     

陕西扶风县城地下水源地开采方案设计

针对严重缺水的陕西省扶风县城供水问题,本文在分析该区水文地质条件和开采现状的基础上,建立了水文地质概念模型,选择了承压水二维非稳定流数学模型进行描述,采用解析法无越流的无界承压含水层干扰井群法求解该数学模型,设计了两套地下水开采方案,计算评价水源地可开采资源量,并对两套方案的计算结果进行了讨论分析,建议选取第二套方案,布井19眼,设计开采量19500m3/d,为拟建城区水源地供水工程新增1.5万m3/d～1.9万m3/d可开采水量提供了依据.     

Reconstructing hydrodynamic flow parameters of the 1700 tsunami at Cannon Beach, Oregon, USA

Coastal communities in the western United States face risks of inundation by distant tsunamis that propagate across the Pacific Ocean as well as local tsunamis produced by great (M_w?>?8) earthquakes on the Cascadia subduction zone. In 1964, the M_w 9.2 Alaska earthquake launched a Pacific-wide tsunami that flooded Cannon Beach, a small community (population 1640) in northwestern Oregon, causing over $230,000 in damages. However, since the giant 2004 Indian Ocean tsunami, the 2010 Chile tsunami and the recent 2011 Tohoku-Oki tsunami, renewed concern over potential impacts of a Cascadia tsunami on the western US has motivated closer examination of the local hazard. This study applies a simple sediment transport model to reconstruct the flow speed of the most recent Cascadia tsunami that flooded the region in 1700 using the thickness and grain size of sand layers deposited by the waves. Sedimentary properties of sand from the 1700 tsunami deposit provide model inputs. The sediment transport model calculates tsunami flow speed from the shear velocity required to suspend the quantity and grain size distribution of the observed sand layers. The model assumes a steady, spatially uniform tsunami flow and that sand settles out of suspension forming a deposit when the flow velocity decreases to zero. Using flow depths constrained by numerical tsunami simulations for Cannon Beach, the sediment transport model calculated flow speeds of 6.5?C7.6?m/s for sites within 0.6?km of the beach and higher flow speeds (~8.8?m/s) for sites 0.8?C1.2?km inland. Flow speed calculated for sites within 0.6?km of the beach compare well with maximum velocities estimated for the largest tsunami simulation. The higher flow speeds calculated for the two sites furthest landward contrast with much lower maximum velocities (<3.8?m/s) predicted by numerical simulations. Grain size distributions of sand layers from the most distal sites are inconsistent with deposition from sediment falling out of suspension. We infer that rapid deceleration in tsunami flow and convergences in sediment transport formed unusually thick deposits. Consequently, higher flow speeds calculated by the sediment model probably overestimate the actual wave speed at sites furthest inland.     

贵州境内乌江水电梯级开发联合生态调度

为保护乌江干流水生生态系统,实现水能资源开发和生态环境双赢,进行乌江水电梯级开发联合生态调度。分析计算了乌江主要生态控制断面洪家渡、乌江渡和思林的最小、适宜及理想生态流量过程;构建了乌江干流梯级水电站多目标联合优化调度模型,采用智能优化算法对其进行求解。计算得到乌江干流9座水库多年平均发电量和典型年年发电量、3个主要控制断面的生态用水保证率及其典型年水库调度过程。结果表明,通过乌江干流梯级水电站联合优化调度,在保证水电站防洪安全和发电效益正常发挥的同时,可提高乌江干流生态流量保证率;对于偏枯年和枯水年,即使通过梯级水电站优化调度,其理想生态流量用水需求也难以满足。