Construction, storage capacity and economics of an underground warehousing – logistics center in Athens, Greece

Interest in underground development is gaining ground in Greece, particularly in Athens, and is driven mainly by the sorely high land prices and the lack of adequate surface space. This paper focuses on the design of an underground Warehousing – Logistics Center (WLC) in the wider metropolitan area of Athens; the center is developed using the room and pillar mining method. The main concept of the paper is that creating an underground space that can host a particular use is not enough, especially in countries attempting their first steps in underground development. The key point is to prove that such underground facilities can be as functional as a respective surface one and at the same time be economically competitive. Based on this, the underground WLC's layout, storage capacity and operational issues were thoroughly examined. The paper provides cost data regarding the construction cost, as well as the development cost. Furthermore, the project was evaluated by means of an investment plan using the NPV and IRR criteria taking into account the selling of the produced aggregates on the market. The results of the analysis not only underline the feasibility of the plan, but also render it a very attractive investment.     

Performance study of underground thermal storage in a solar-ground coupled heat pump system for residential buildings

This paper is performed to analyze the performance of underground thermal storage in a solar-ground coupled heat pump system (SGCHPS) for residential building. Based on the experimental results, the system performance during a longer period is simulated by the unit modeling, and its parametric effects are discussed. The results show that the performance of underground thermal storage of SGCHPS depends strongly on the intensity of solar radiation and the matching between the water tank volume and the area of solar collectors. Compared with the solar radiation, the variations of the water tank temperature and the ground temperature rise lag behind and keep several peaks during the day time. For the case of Tianjin, the efficiency of underground thermal storage based on the total solar radiation and absorbed solar energy by the collectors can reach over 40% and 70%, respectively. It is suggested that the reasonable ratio between the tank volume and the area of solar collectors should be in the range of 20–40 L/m².     

Anchoring of empty underground tanks against underground-water-induced floatation by using arched cable system

An empty underground storage tank, constructed within the fluctuating rise and fall of underground water level, can move upward by an uplifting pressure equal to the weight of the displaced water minus the self weight of the tank. Several methods are used to hold such tanks in position. Piled foundations are used as one of these solutions, in which the piles are subjected to pulling out forces. Practically this solution has many structural defects in addition to its high cost. In this article, it is proposed that an arched cable system could be used to anchor empty reinforced concrete rectangular tanks against any floatation caused by the uplifting pressure which might be generated by the rise of the underground water level. An arched cable is placed through a parabolic profile duct embedded in the concrete of each of the tank long walls and anchored at its ends. The equations required to design such system are demonstrated by using an illustrative example.     

太阳能供暖系统室内地下储热水箱的散热规律

针对太阳能地下储热水箱布置位置的不同,利用Fluent程序对太阳能储热水箱散热进行数值模拟和计算,得出在不同工况下,储热水箱周围土壤的温度场分布。同时,建立地下储热水箱的物理模型和数学模型,分析地下储热水箱的换热特性,并结合实际工程,验证其地下储水箱全年散热量和储能量,获得水箱顶板损失量与总散热量关系。计算结果表明,在相同工况下,冬季室外储水箱能量的散失量远高于室内,室内地下储水箱顶部散热量减少,因此该方式可以用来抵消这部分能量所需的集热器面积的减少,提高储热水箱的储热效率以及减少用户投资。     

Application of heat transfer analysis for frozen food storage caverns

Supply of high quality preserved food products has always been very important. Storage of food in underground caverns is superior over food storage tanks constructed at surface from an energy conservation point of view. There are a lot of underground openings excavated in tuff used for the storage of fruits and vegetables at the Cappadocia Region of Turkey. However, there has not been any attempt to use these underground openings for deep frozen food storage and related heat transfer details. The main purpose of this work was to investigate underground food storage openings in the Cappadocia Region and their potential use for frozen food storage. Details of heat transfer around openings for various geometrics in three-dimensional have been modelled by using a finite element software package called MARC. For the sake of comparison, heat transfer details around a similar opening excavated in granite were also determined. A comparison of underground caverns excavated in tuff and granite with a surface deep freeze storage tank was also made by both taking construction and operational costs into account. Construction of an underground deep freeze storage cavern excavated in tuff would cost one half of a same size surface tank whereas, energy loss due to heat transfer is three times lower in the favour of underground storage cavern opened in tuff.     

合流制溢流污染控制实践:以岳阳蛇皮套泵站为例

岳阳市蛇皮套泵站及调蓄池改造工程是典型的合流制溢流污染控制工程,设计通过科学的管网水力模型与系统的水文建模分析,基于海绵城市建设理念,在排口末端采用调蓄池与生态滤池组合工艺处理溢流水,达到精准治污的效果,并将处理设施结合景观设施进行设计,将黑臭水体改造为海绵公园。介绍了项目的基本情况以及泵站、调蓄池、生态滤池的设计规模和运行工况,并对设计方案进行长历时水文模型验证。模拟结果表明,在经济允许的情况下,采用该工艺措施可使受纳水体的溢流污染得到一定的控制,单位硬化面积的溢流COD污染负荷低于250 kg/(hm^2·a),生态滤池出水COD平均值为10.2 mg/L,生态滤池溢流频次为12.2次/年,调蓄池截流的COD污染负荷为2 343 t/a,生态滤池去除的COD污染负荷为105 t/a,分别占COD污染总量的48.2%和2.2%,而溢流污染量仅占2.3%,达到了一定的面源污染控制要求,生态环保效益明显。     

盐岩地下储气库地表沉降风险失效概率的计算分析

盐岩地下储气库在运营过程中,因盐腔蠕变体积收缩引起地表沉降变形,从而对盐矿区地面设施(如建筑物、桥梁、路基等)产生不良影响,为了评估该影响,建立盐岩地下储气库地表沉降风险失效概率的计算方法,即：首先通过数值计算获得盐岩储气库的体积收缩率,然后通过SRAKA SCHOBER矿山法获得盐腔体积收缩引起的地表沉降,并建立地表沉降风险功能函数表达式,最后采用基于随机变量的蒙特卡洛方法可计算获得盐腔体积收缩引起的地表沉降风险失效概率。将该方法应用于金坛盐岩地下储气库,有效获得储气库体积收缩引发的地表沉降对盐矿区地面建筑的影响,为储气库区地面设施风险安全控制提供理论依据。     

An underground pumped storage scheme in the Bukit Timah Granite of Singapore

Pumped storage is an energy storage method that involves the pumping of water from a lower reservoir to an upper reservoir during off-peak period using low cost power and releasing of the water from the upper reservoir to produce electricity during peak load period. Because of the very small and relatively flat land area of Singapore, a conventional surface pumped storage plant is not feasible. A pumped storage plant can be constructed here by siting the upper reservoir in one of the many abandoned granite quarries and by placing the lower reservoir and the powerhouse underground in the Bukit Timah granite, which is sound, massive and impervious. The capital costs for a pumped storage plant could be the same as those of an oil-fired plant of comparable size. When the very high cost of land in Singapore is taken into account, an underground pumped storage scheme for peaking purposes becomes attractive.     

Test running of an underground food storage cavern in Korea

This paper mainly reports the details of the f rst real test of food storage in the underground food storage cavern in Korea. Pear and apple were selected, and the change of indices such as the rate of soundness, moisture content, total acid, and hardness were monitored with the temperature and humidity in and around cavern. The results showed that the fruits were stored in better quality in the case of underground storage with cooling than natural underground condition or surface storage tank.     

Policy and legal frameworks for underground natural gas storage in Iran

Underground natural gas storage is a process with operational and economic benefits that balances a variable demand market with a constant energy supply. It increases gas service reliability at peak periods and enables the suppliers to meet gas demands. Thus, the sufficiency and responsiveness of existing policy and legal framework for developing underground gas storage to provide reliability to industry players require deep analysis.Iranian policymakers set out policies regarding gas storage as an economic decision to manage prospective risks associated with the gas market. However, comprehensive and integrated policies and strategic plans for underground gas storage are not set out to the required extent. Therefore, enacting specific, comprehensive, and integrated laws and regulations is imperative to consider the unique characteristics of underground gas storage. Enabling third-party access to gas storage facilities as a sectoral regulatory mechanism could guarantee competition. In addition, the role of constructive contractual arrangements for developing underground gas storage, founded on the sector's laws and regulations, as a complementary tool to attract investment should not be overlooked. The transfer of ownership of gas and facilities under such contractual arrangements could facilitate the process, incentivizing investment.     

地下水封石油洞库施工期安全风险评估研究

地下水封石油洞库建设具有投资大、无成熟设计施工规范、不确定因素多等特点,建设过程中存在着一定安全风险,开展地下水封石油洞库施工期安全风险评估研究具有重要意义。针对地下水封石油洞库施工期安全风险,从洞库稳定性与水封性两个方面,开展了洞库施工期安全风险评估研究,结合中国首座大型地下水封石油洞库工程对研究结论进行了验证。研究中,开展了地下水封石油洞库风险因子识别,进行了风险因子重要性和引发功能失效概率调查;采用模糊数学方法获得了风险因子模糊权重集和模糊评价集,得到了风险因子影响程度排序;总结了某地下水封石油洞库建设中典型稳定性和水封性风险事故,分析了事故发生原因,并与上文所得风险因子影响程度进行了对比验证。研究结果不但为提高地下水封石油洞库风险管理水平提供支撑,而且还可丰富地下工程安全风险评估研究内容。     

太阳能辅助地源热泵供热运行特性研究

介绍了太阳能辅助地源热泵,对其各装置性能进行了研究。分析了地下埋管换热器进出口水温及有、无蓄热水箱对太阳能辅助地源热泵性能的影响。太阳能辅助地源热泵制热性能系数随地下埋管换热器进口水温的升高呈下降趋势,随其出口水温的升高呈上升趋势。随地下埋管换热器出口水温升高,蒸发器传热量增大。当太阳能辅助地源热泵中无蓄热水箱时太阳能集热器的瞬时集热效率高于有蓄热水箱时的瞬时集热效率。就总体效果而言,有蓄热水箱要优于无蓄热水箱,这样可使地源热泵运行更加稳定。     

合肥市清一冲、清二冲初期雨水径流污染控制方案

合肥市中心城区初期雨水径流污染问题突出,已成为影响地表水环境质量的主要因素之一。在排水系统末端设置调蓄池,可经济有效地控制初期雨水径流污染,降低面源污染对受纳水体水质的影响。以合肥市清一冲、清二冲初期雨水调蓄池设计为例,从设计规模、总体布置形式、进出水设计、冲洗系统设计和除臭设计等5个方面对调蓄池的工艺设计进行阐述,并对调蓄池运行模式和工程设计特点进行分析介绍,旨在为同类初期雨水调蓄池的设计和运行管理提供参考。     

聚乙烯醇纤维补偿收缩混凝土在超大地下工业水池中的应用

在对掺聚乙烯醇(PVA)纤维补偿收缩混凝土试验研究的基础上,结合设置加强带,改进水池墙板水平筋、加强施工质量监控等技术措施,对某超大地下工业水池进行无缝设计和施工。蓄水试验检测结果表明,水池各区格的实际渗漏水量仅占允许渗漏水量的56%～60%,防渗性能满足水池设计要求,达到了预期效果。     

The present state of underground crude oil storage technology in japan

Although Japan is a major consumer of petroleum, it depends almost completely on imports from abroad and thus is easily affected by external conditions concerning petroleum. To reduce this import dependency, Japan is engaged in a long-term program to improve and strengthen its vulnerable position. The program includes the use of underground crude oil storage facilities, construction of which is now in progress. Referring to examples of the underground storage in Europe and America, the technology for these facilities is being developed into a system suited to the natural and social conditions of Japan on the basis of the results of construction and operation of a test plant. This paper reports on the present state of underground oil storage technology in Japan.     

An underground bus terminal in Amsterdam: Legal and policy issues

In many large urban centres, there is considerable pressure to expand public transport interchanges in order to accommodate increased passenger volumes. However, the lack of space in city centres means that innovative solutions often have to be found before such expansion plans can be realised. A particular case is the interchange at Amsterdam Central Station, where there is an urgent need for better facilities for bus passengers. The growing popularity of bus travel has led bus companies to investigate the feasibility of building an underground bus terminal below the harbour area in front of the railway station. This article discusses the advantages offered by this concept and reviews its implications for local public transport policies. Attention is also given to the process of developing the project by obtaining social and political support for it. Finally, the design of the proposed bus station is presented and a number of specific features of the underground situation are highlighted.     

Assessing the financial and environmental performance of underground automated vacuum waste collection systems

The development of underground infrastructures for the efficient management and collection of urban waste streams offers great advantages and solutions in tackling problems relating to these activities. Nevertheless, in order for such alternatives to gain acceptance and be further utilized, besides their advantages in effectiveness and in environmental friendliness, they must prove their efficiency in terms of financial performance. The paper analyses modern techniques available as the underground automated vacuum waste collection system (AVAC) and presents the financial and environmental assessment of a proposed system in replacement of an existing conventional waste collection scheme in Athens. The comparative financial assessment is undertaken using the equivalent annual cost methodology (EAC) where the capital expenditures and annual operational and maintenance costs for both alternatives are calculated. The findings show that these two systems have roughly the same cost performance using the equivalent annual cost analysis. Yet, they have noticeably differentiations in the operational and capital costs with the AVAC system having almost 40% lower operational cost requirements. Finally the environmental comparison of the alternatives focusing on the city’ air quality is further highlighting the superiority of the AVAC scheme. Thus, the selection of such a fixed underground infrastructure over a conventional one can be pursued as it offers equivalent financial performance and yet enhanced operational and environmental characteristics.     

Proposed future underground projects in sweden

The author describes a number of underground projects proposed by Swedish architects, engineers and planners. These include an underground wind tunnel built in rock, an underground museum, underground gas storage facility, an underwater traffic tunnel for Stockholm, and a large conference center under Stockholm, an underground concert hall in Jönköping, underground grain storage and oil storage facilities in rock caverns, and an underground pipeline to bring fuel to Stockholm airport, underground peak power-stations, and an underground waste treatment facility.     

静置状态蓄冷水箱斜温层的实验与模拟研究

采用实验方法研究静置状态蓄冷水箱斜温层上端位置、下端位置、斜温层厚度随时间的变化,采用模拟方法在容积一定的前提下,研究静置状态蓄冷水箱横截面积对斜温层的影响。实验蓄冷水箱的长、宽、高为0.6m、0.6 m、3.6 m,实验条件下,斜温层上端位置1 h后趋于稳定(高度基本保持在1.06 m),斜温层下端位置逐渐下降(高度由0.80 m降至0.25 m)。蓄冷水箱斜温层厚度初始为0.23 m,经历8 h静置后变为0.81 m。在容积一定的前提下,建立与实验蓄冷水箱尺寸相同的蓄冷水箱模型(称为原型蓄冷水箱)以及4个与实验蓄冷水箱容积相同但高不同的蓄冷水箱模型作为对照(对照蓄冷水箱1~4的横截面尺寸分别为0.7 m×0.7 m、0.8 m×0.8 m、0.9 m×0.9 m、1.0 m×1.0 m)。随时间延长,斜温层上端位置、下端位置、斜温层厚度的实验结果与模拟结果(原型蓄冷水箱)的变化基本一致,模拟结果可以准确反映斜温层上端位置、下端位置及斜温层厚度。在模拟条件下,对于原型蓄冷水箱、对照蓄冷水箱1~4,在0时刻(水泵停止时)斜温层形状扁平,随着时间推移变为上凸下凹。原型蓄冷水箱、对照蓄冷水箱1~4斜温层厚度均随时间延长而增大,相同时间原型蓄冷水箱、对照蓄冷水箱1~4斜温层厚度的变化虽无规律可循,但相差不大。原型蓄冷水箱、对照蓄冷水箱1~4斜温层截面积(蓄冷水箱竖向中间截面上由11.1℃与6.9℃等温线及水箱壁面包围的面积)均随时间延长而增大。相同时间,斜温层截面积占比由大到小的顺序为对照蓄冷水箱4、对照蓄冷水箱3、对照蓄冷水箱2、对照蓄冷水箱1、原型蓄冷水箱。蓄冷水箱容积一定的条件下,横截面积越小的蓄冷水箱斜温层截面积占比越小,分层效果越好,可利用的冷水越多。长时间静置,易导致斜温层增大。     

大型LNG储罐保冷性能的研究

根据LNG储罐的结构,给出储罐热流量和静态蒸发率的计算方法。利用该方法对济南某3×104m3双金属LNG储罐热流量和静态蒸发率进行计算,分析储罐热流量的影响因素。结果表明:案例储罐的静态蒸发率为0.074 8%,静态蒸发率较小,储罐的保冷性能良好。环境温度对储罐热流量的影响较大,环境风速和充满率对储罐热流量的影响较小。