An Overview of Recently Developed Coupled Simulation Optimization Approaches for Reliability Based Minimum Cost Design of Water Retaining Structures

This paper reviews several recently-developed techniques for the minimum-cost optimal design of water-retaining structures (WRSs), which integrate the effects of seepage. These include the incorporation of uncertainty in heterogeneous soil parameter estimates and quantification of reliability. This review is limited to methods based on coupled simulation-optimization (S-O) models. In this context, the design of WRSs is mainly affected by hydraulic design variables such as seepage quantities, which are difficult to determine from closed-form solutions or approximation theories. An S-O model is built by integrating numerical seepage modeling responses to an optimization algorithm based on efficient surrogate models. The surrogate models (meta-models) are trained on simulated data obtained from finite element numerical code solutions. The proposed methodology is applied using several machine learning techniques and optimization solvers to optimize the design of WRS by incorporating different design variables and boundary conditions. Additionally, the effects of several scenarios of flow domain hydraulic conductivity are integrated into the S-O model. Also, reliability based optimum design concepts are incorporated in the S-O model to quantify uncertainty in seepage quantities due to uncertainty in hydraulic conductivity estimates. We can conclude that the S-O model can efficiently optimize WRS designs. The ANN, SVM, and GPR machine learning technique-based surrogate models are efficiently and expeditiously incorporated into the S-O models to imitate the numerical responses of simulations of various problems.

Structural mechanism and construction method of mud and water inrush in Xiangyun tunnel of Guangtong-Dali railway

Mud and water inrush in tunnel is a common problem in the construction process. Nowadays, the research and classification on this are mostly focused on karst situations. According to the characteristics of the surrounding rock and damage forms of the tunnel in the studied area, the author analyzed the geological and structural characteristics of mud and water inrush in tunnel and obtained their construction type. Meanwhile, the advanced water detection under the complex geological conditions was studied by using induced polarization method, transient electromagnetic method and three-dimensional seismic method, it can be concluded that the water-rich fracture zone exists within the detection range with a risk of large mud and water inrush disaster. The concrete construction treatment measures are put forward:①cement-water glass binary slurry is selected as the material for ground and hole grouting, its advantage is that the gel time can be controlled, and it has certain grout ability in the strata with large permeability coeffcient, which is conducive to excavate construction immediately after grouting.②applying the mature retrograde grouting construction can reduce grouting time and improve the excavation efficiency.

Development of key additives for organoclay-free oil-based drilling mud and system performance evaluation

Traditional oil-based drilling muds(OBMs) have a relatively high solid content, which is detrimental to penetration rate increase and reservoir protection. Aimed at solving this problem, an organoclay-free OBM system was studied, the synthesis methods and functioning mechanism of key additives were introduced, and performance evaluation of the system was performed. The rheology modifier was prepared by reacting a dimer fatty acid with diethanolamine, the primary emulsifier was made by oxidation and addition reaction of fatty acids, the secondary emulsifier was made by amidation of a fatty acid, and finally the fluid loss additive of water-soluble acrylic resin was synthesized by introducing acrylic acid into styrene/butyl acrylate polymerization. The rheology modifier could enhance the attraction between droplets, particles in the emulsion via intermolecular hydrogen bonding and improve the shear stress by forming a three-dimensional network structure in the emulsion. Lab experimental results show that the organoclay-free OBM could tolerate temperatures up to 220 ?C and HTHP filtration is less than 5 m L. Compared with the traditional OBMs, the organoclay-free OBM has low plastic viscosity, high shear stress, high ratio of dynamic shear force to plastic viscosity and high permeability recovery, which are beneficial to penetration rate increase, hole cleaning and reservoir protection.

铝盐聚合醇钻井液体系在辽河油田的应用

辽河油田沈北区块上部地层含大段软泥岩,易水化膨胀缩径,下部地层水化分散强,易发生周期性垮塌,常规的钻井液体系不能有效稳定井壁,常引发井下复杂情况。研制出了强抑制性铝盐聚合醇钻井液体系,该钻井液由于铝盐和聚合醇的协同作用,具有优良的润滑和抑制性能。该体系在沈625-10-22井、沈625-14-34井及沈625-18-30井钻进过程中表现出良好的抑制性,减少了钻井复杂情况,井下安全,井眼规则,与同区块使用聚合物分散体系的井相比,平均井径扩大率降低7.95%-11.77%,并且降低了钻井液的使用密度。其成功应用证明,铝盐聚合醇钻井液抑制性和井壁稳定能力强,具有明显的防塌效果,可满足沈北区块沙河街地层钻进的需要。

二氧化碳泡沫压裂液研究与应用

简介了泡沫压裂液发展现状及影响CO2泡沫压裂液性能的主要因素。基于添加剂的研制(起泡剂FL 36,酸性交联剂AC 8)和筛选,得到了CO2泡沫压裂液的典型配方:0 6%HPG+1 0%FL 36+1 0%粘土稳定剂+0 1%破乳助排剂+0 06%过硫酸铵+1 5%AC 8,测定了该配方的各项性能。基液粘度75mPa·s(25℃,170s-1),pH值7 0;泡沫半衰期300min(25℃,0 1MPa),pH值4 0。泡沫干度(泡沫质量)为70%和60%的CO2泡沫压裂液在40～50min内可维持粘度>80mPa·s。在流动回路装置上测得泡沫干度增大时粘度增大,在高干度下形成气泡细小均匀的稳定泡沫。滤失系数在2 9×10-4～4 2×10-4范围。对岩心渗透率的伤害率为13 6%(22支岩心平均值),而水基压裂液的伤害率高达60%。在70℃数小时完全破胶。大粒径(0 9mm)陶粒在干度40%和70%的CO2泡沫压裂液中沉降速度<0 06cm/s。常温、1Hz下G′和G″随干度增大而增大,且G″>G′。江苏油田低渗油藏3口井实施CO2泡沫压裂取得了明显增油效果。表4参3。

Catastrophe theory-based risk evaluation model for water and mud inrush and its application in karst tunnels

This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the dangerousness of this geological disaster.The losses that are caused by water and mud inrush are taken into consideration to account for its harmfulness.Then a risk evaluation model based on the dangerousness-harmfulness evaluation indicator system is constructed,which is more convincing in comparison with the traditional methods.The catastrophe theory is used to evaluate the risk level of water and mud inrush and it has great advantage in handling problems involving discontinuous catastrophe processes.To validate the proposed approach,the Qiyueshan tunnel of Yichang-Wanzhou Railway is taken as an example in which four target segments are evaluated using the risk evaluation model.Finally,the evaluation results are compared with the excavation data,which shows that the risk levels predicted by the proposed approach are in good agreements with that observed in engineering.In conclusion,the catastrophe theory-based risk evaluation model is an efficient and effective approach for water and mud inrush in karst tunnels.

改性天然高分子水基钻井液的研究与应用

简介了4种对环境无害的固态的水基钻井液处理剂的合成及性能:改性天然高分子类包被剂IND30和降滤失剂NAT20,无萤光白沥青NFA25(部分溶于水、部分溶于油的改性油类物质)及粉状聚合醇PGCS1(EO/PO共聚物)。报道了用膨润土和这4种处理剂配制的各种实验钻井液的组成和性能:基本配方钻井液(钻井液1)、强抑制性钻井液(钻井液2,另加入一种小阳离子页岩抑制剂)、抗盐钙污染钻井液(加入35%NaCl和1%CaSO4),抗膨润土污染钻井液(加入4%钙膨润土)。这4种钻井液在原配制状态和在120℃、140℃滚动16小时后,各流变参数均在合理范围,API滤失量≤5 2mL,HTHP滤失量≤20mL。某油藏储层钻屑在钻井液1、2中于140℃滚动16小时后,回收率分别为91 2%和96 7%;该储层岩心被原配制和在140℃滚动16小时后的钻井液1、2污染后,渗透率恢复率为88 2%～91 6%。4种处理剂溶液,钻井液1、2及两口井使用的钻井液均无毒,EC50>3×104mg/L。该体系多功能水基钻井液已在塔里木、克拉玛依等油田10余口井钻井中获得成功应用,最长裸眼长度达5324 45m,井眼扩大率仅5%～10%。详细介绍了在LG区块使用的钻井液分井段组成、维护及性能。表4参3。

Conjunctive Utilization of Water Resources at the Yulin Coal-Mine Base in China

Shortages in water resources and the fragile ecosystem by coal-mine water affect the Yulin coal-mine base in northwest China, so taking coal-mine water into account is an important issue for the sustainable management of water resources. This paper aims to explore how the Yulin coal-mine base can improve its conjunctive utilization of water resources. Integrated utilization is proposed by establishing a multi-objective, multi-water-source, optimal-allocation model;setting up an integrated information platform;and giving very useful measures and policy suggestions to the local government. Finally, this research can also serve as an example of integrated water utilization for other energy bases.

基于地表水和地下水联合调控的水资源配置模型研究

基于水库与地下水联合运用的耦合模拟模型,建立了基于河道内与河道外生态环境需水及下游灌溉用水需求双重作用的水资源优化调控模型,研制和开发了集数据库、模型库和人机交互界面等于一体的水资源优化调控模型计算软件,并以沈阳市沈北地区为例进行了实证研究。通过对石佛寺供水系统不同组合方案长系列逐月调算和对比分析,提出了推荐的石佛寺供水系统地表水与地下水联合优化调控模式和设计供水规模。研究结果为沈阳市的协调发展尤其是沈北地区未来的跨越式发展提供了安全的供水保障,且可推动我国地表水与地下水联合优化调控理论研究和应用,为其他地区和流域开展类似工作提供参考。

基于混合模型的灌河水环境容量研究

针对灌河口地区污染源分布特点,采用一维和二维水质模型相结合的水环境容量计算方法,对灌河的水环境容量进行了计算分析。结果表明,在90%水文保证率下,灌河COD水环境容量为4247t/a,NH3-N水环境容量为561t/a,得出灌河流域已不同程度受到污染,提出控制污染的方法建议,供相关部门在治理灌河的污染、改善灌河水环境以及开发利用灌河方面作参考。

水资源复合系统动力学仿真模型研究

基于系统动力学原理与方法,构建了水资源—社会—经济—生态环境的复合系统动力学模型,并以大连市1995～2004年的城市用水、社会经济等统计资料为基础数据进行了模拟和预测。结果表明,模拟值与实际值基本吻合,对实现水资源与社会、经济、生态环境的协调发展具有重要作用。

基于聚类分析的工程移民收入水平恢复评价

移民的收入水平分析是移民监测与评估的重要内容。采用聚类分析来对移民的人均收入分布进行统计分析,考虑搬迁前后的时间历程,分析其变化趋势,利用马尔科夫模型进行人均纯收入的预测,并以湖南长江干堤加固工程作为实证分析。

Study on Parameters Selection of Oil-Based Mud Formation Imaging Tool (OBIT) Based on FEM

In a typical oil-based mud environment, the borehole fluid and mud cake are highly resistive and will not permit any significant current flow from the tool to the formation. In order to overcome the high insulation effect of the medium, measurement current must be injected at a relative high frequency since most of the conduction is due to capacitive coupling. In this paper, an OBIT numerical model based on four-terminal method was established to study the tool responses during the measurements. The influences of tool parameters, such as the area and distance of current-injector electrodes, inject frequency, distance of button sensors, standoff and electrical properties of borehole fluid, the tool responses, were investigated and the tool optimization was discussed.

Development of an Ontology-Based Knowledge Network by Interconnecting Soil/Water Concepts/Properties, Derived from Standards Methods and Published Scientific References Outlining Infiltration/Percolation Process of Contaminated Water

The present work deals with the development of an Ontology-Based Knowledge Network of soil/water physicochemical & biological properties (soil/water concepts), derived from ASTM Standard Methods (ASTMi,n) and relevant scientific/applicable references (published papers—PPi,n) to fill up/bridge the gap of the information science between cited Standards and infiltration discipline conceptual vocabulary providing accordingly a dedicated/internal Knowledge Base (KB). This attempt constitutes an innovative approach, since it is based on externalizing domain knowledge in the form of Ontology-Based Knowledge Networks, incorporating standardized methodology in soil engineering. The ontology soil/water concepts (semantics) of the developed network correspond to soil/water physicochemical & biological properties, classified in seven different generations that are distinguished/located in infiltration/percolation process of contaminated water through soil porous media. The interconnections with arcs between corresponding concepts/properties among the consecutive generations are defined by the relationship of dependent and independent variables. All these interconnections are documented according to the below three ways: 1) dependent and independent variables interconnected by using the logical operator “depends on” quoting existent explicit functions and equations;2) dependent and independent variables interconnected by using the logical operator “depends on” quoting produced implicit functions, according to Rayleigh’s method of indices;3) dependent and independent variables interconnected by using the logical operator “related to” based on a logical dependence among the examined nodes-concepts-variables. The aforementioned approach provides significant advantages to semantic web developers and web users by means of prompt knowledge navigation, tracking, retrieval and usage.

自催化交联体系室温硫化水性硅橡胶研究

以α官能团硅烷为自催化交联剂制备了单组分室温硫化(RTV 1)水性硅橡胶,对其贮存稳定性、粘接性及硫化胶力学性能进行了研究。结果表明,该体系下可制备低模量的RTV水性硅橡胶,但它的贮存稳定性较差;pH为9.5及以上时,水性硅橡胶的粘接力及持粘力较好;在一定范围内,使用高补强填料、增加填料用量、使用含氯原子硅烷偶联剂、增加硅烷偶联剂用量等都可以使水性硅橡胶的拉伸强度提高,硬度增大,伸长率下降。

地基GPS水汽遥测系统远程通讯与控制系统及其初步应用

地基GPS遥感大气水汽技术是20世纪90年代发展起来的一种全新的大气观测手段,建立科学合理的GPS数据实时采集通讯网,实时下载观测数据,可为地基GPS资料应用开发成果的业务化推广提供必要的技术支撑,是地基GPS大气水汽遥感系统可否推广应用的一项关键指标。介绍了采用Modem、依托公共电话网(PSTN)建立起来的远程数据通讯和控制系统。使用该系统可通过电话拨号的方式,对GPS水汽探测网内指定的GPS接收机的参数进行设置,还可以下载该接收机内存储的数据文件。该通讯系统的应用,增强了整个GPS遥感大气水汽探测网的可维护性,为最终实现GPS水汽探测网的业务化运行奠定了一定的理论和实践基础。针对该系统存在的数据下载速度慢,依赖人工操作等缺陷,提出了解决问题的思路。

适用于滩海地区的正电聚醇/甲酸盐钻井液

目前,水基钻井液仍然是滩海钻井的首选钻井液。正电聚醇钻井液和甲酸盐钻井液自从20世纪90年代在现场应用以来,均表现出良好的性能。为运应滩海钻井的需要,充分发挥正电聚醇和甲酸盐的优势,研制出了一种新型的正电聚醇-甲酸盐钻井液体系。在地层孔隙压力较低或较高时,分别利用正电聚醇或甲酸盐作为主要处理剂以确保钻井液具有良好的性能并维持较低的固相含量。分析了正电聚醇、甲酸盐的作用机理及其协同增效作用。室内试验评价了该钻井液的抗温性、抑制性、保护油气层性能以及用甲酸盐加重对钻井液性能的影响。该钻井液在埕海4和庄海12井等进行了初步应用.在应用中钻井液粘度变化不大,埕海4井和庄海12井的平均井径扩大率分别为9.19%和6.91%,明显低于邻井;起下钻及下套管正常,无遇阻情况,电测顺利。室内试验和现场应用结果均表明,正电聚醇和甲酸盐的协同作用,可使钻井液具有防塌、润滑、环保和储层保护等多种功能。

双保仿油基改性MEG的研究与应用

MEG是近年来利用半透膜机理优选出的一种优质处理剂,有良好的润滑性、热稳定性和页岩抑制性,无荧光、易生物降解。但MEG本身为液体,加量偏高(10%-30%)。通过大量的文献调研和试验,成功地将MEG液体制成固体,不仅保持了MEG原液体的基本性能,又增加了MEG抑制能力的成分。由性能评价得知,改性MEG单剂具有良好的页岩抑制性及润滑性,经150℃老化后MEG钻井液流变性能、滤失性能、pH值变化不明显,随着改性MEG加量的增加,钻井液性能持续得到改善,综合考虑经济效益,改性MEG加量定为7%。现场应用表明,MEG钻井液具有较强的悬浮性和携带岩屑的能力及良好的护壁作用,抗膏岩污染能力强,流变性易于调节;使用MEG钻井液钻进的井机械钻速比同类井提高15%;并具有良好的保护油气层的作用,郑607-平6井试油日产油量为52t,是邻井的3倍。

Physical and chemical changes of water in the deep interior of the Earth―Decrepitation-style mud-volcano-earthquake―A bright lamp to shed light on the mysteries of the deep interior of the Earth

The 2008-05-12 Wenchuan mud-volcano-earthquake was accompanied with eruption of a huge volume of gas and stone,revealing that earthquakes generally result from instant reverse phase explosion of supercritical water(SCW) at the supercritical point.In the deep parts of the crust and mantle there still exists a large amount of supercritical water equivalent in order of magnitude to that of the Earth's hydrosphere.Soft fluids which exist in the MOHO at the top of the upper mantle are the so-called deep supercritical fluids(SCWD).Supercritical water(SCW) has n×103 times strong capability to dissolve gas.Its viscosity is extremely low and its diffusivity is extremely strong.Therefore,it can naturally migrate toward a region with relatively negative pressure.In the steep break zone of the MOHO at the 57-65 km depth beneath the earthquake belt,due to mutation of overburden pressure,SCWD can automatically separate out CaSiO3 and other inorganic salts,evolving into the SCW(H2O-CO2-CH4O system.In going upwards to the 10-20-km depth of the crust SCW will be accumulated as an earthquake-pregnant reservoir in the broken terrain.The phase-transition heat of SCW is estimated at 606.62 kJ/kg and the reverse phasing kinetic energy is 2350.8 kJ/kg.When automatic exhaust at the time of decompression reaches the critical pressure(Pc),the instant explosion reverse phase will be normal-state air water.It will release a huge volume of energy and high-kinetic-energy gas which has been expanded by a factor of 1000,leading to the breaking of the country rocks overlying the earthquake-pregnant reservoir,thus giving rise to a Ms 8.0 earthquake.As a result,there were formed eruptive and air-driven(pneumatic) debris flows whose volumatric flow rate reaches n×1014 m3/s,and their force greatly exceeds the power of INT explosive of the same equivalent value.

新型水性有机硅水泥混凝土防水剂的研制

根据高分子反应接枝共聚原理,在无溶剂的条件下,将硅烷偶联剂-氨丙基三乙氧基硅烷(APTES)通过与甲苯二异氰酸酯(TDI)反应引入到204水溶性有机硅主链中,成功地制备了一系列含活性硅氧基有机硅半透明液、微乳液及乳液型水泥混凝土防水剂。系统研究了该类防水剂对水泥沙浆的力学强度、吸水率等性能的影响。结果表明,含不同量活性硅烷偶联剂的水性有机硅作为水泥防水剂具有优良的应用性能,有望作为新型水性有机硅防水剂获得大规模推广应用。