逆作法在超深地下车库中的应用

针对市区中心繁华地段施工的特点,通过梅园中心地下车库工程实例详细介绍了逆作法施工工艺、技术要点及其实施效果,指出该方法具有安全、经济、工期短及绿色文明施工等特点,值得进一步推广。     

Vacuum glazing—A new component for insulating windows

The substantial progress in the science and technology of vacuum glazing that has occurred over the past few years is reviewed. Vacuum glazing up to 1 m × 1 m in size has been produced with an air-to-air, mid-device thermal conductance as low as 0.90 W m⁻² K⁻¹, compared with 1.3 W m⁻² K⁻¹ for high performance double glazing. The mechanical tensile stresses in vacuum glazing due to pressure and temperature differentials are well understood, and appear to be tolerably small. The internal vacuum is high, and extremely stable over long times at moderate temperatures. The likely cost of volume production of vacuum glazing should be only slightly greater than for high performance double glazing.     

Diagonal network analysis — a new technique for project managers

Owing to its numerical rather than visual presentation, numerical network analysis, a term used to encompass techniques such as the critical path method, has never really been accepted as a working tool in the building industry. To fill this gap, diagonal network analysis (DNA) was developed. The DNA chart displays in visual terms everything that numerical network analysis gives only in numerical terms, and shows overlapping of activities without having to construct complex ladders. An arrow programme need not be drawn first as the program does this for the user. The development of a program that could draw a DNA chart from input data simple enough for even a builder to understand is described.     

Dye-sensitized-photo-oxidation—a new approach to the treatment of organic matter in sewage effluents

A new approach to the oxidation of organic matter in municipal wastewaters by photosensitization is described. Samples of aerated sewage effluents containing an added dye-sensitizer were exposed to u.v.-lamp or solar radiation. The photochemical oxidation of the sewage caused decreases in the content of the fecal coliform, of the chemical oxygen demand and of the methylene blue-active substances by 100, 67 and 90% of their initial values, respectively. The effluents obtained after the removal of the dye, by precipitation with bentonite clay, were colorless, non-odorous and with the amount of suspended solids considerably reduced.     

Colour and turbidity removal with reusable magnetite particles—IV: Alkali activated magnetite—A new solid. Reusable coagulant-adsorbent

Alkali treated magnetite (Fe₃O₄) is shown to be an excellent solid coagulant-adsorbent which is regenerable and reusable. It is effective for the removal of colour and turbidity from water. Alkali treated magnetite can be used alone or in conjunction with another primary inorganic coagulant or organic flocculant. Because of the accelerated kinetics of coagulation and particularly of sedimentation, this new technique is 3–6 times faster than the conventional coagulation-flocculation-sedimentation process. It also appears that filtration of the product water may not be necessary. Regeneration of the spent magnetite is achieved by contacting the used magnetite with 0.1 M sodium hydroxide. The development of the process on the laboratory scale using a jar test technique is discussed.     

Strategy, the final frontier

All agree that every organisation needs a strategy. Every organisation claims to have one. Yet few agree as to its appearance, meaning and intention. Most definitions have one thing in common: that strategy is at the very root of an organisation. strategy is a set of choices about ways of dealing with the political, economic, social and technological environment, and which serve to guide and co-ordinate all the plans and actions that the organisation needs. The author discusses the theory and practice of business strategy with particular reference to European Gas Turbines. Strategic approaches and layered strategies are discussed     

R&D networks and regional knowledge production in Europe: Evidence from a space‐time model

In this study we estimate space‐time impacts of the embeddedness in R&D networks on regional knowledge production using a dynamic spatial panel data model with non‐linear effects for 229 European NUTS 2 regions in the period 1998–2010. Embeddedness refers to the positioning in networks where nodes represent regions that are linked by joint R&D projects funded by EU Framework Programmes. We find evidence that increasing embeddedness in EU funded R&D networks leads to positive immediate impacts on regional knowledge production, and that regions with lower levels of own knowledge endowments more likely exploit the positive effects. However, the long‐term impacts of a region's embeddedness in these R&D networks are comparatively small.     

Building regulations—the international scene

Building regulations vary internationally in their objectives and in the responsibilities they place upon designers and contractors, but they generally depend upon national or international codes and standards for their technical requirements. The systems operated in a number of European countries are discussed in this paper in terms of the internal environment of buildings and general considerations of public safety and health. The author refers to the influence of the relevant CIB Working Commissions in establishing internationally agreed standards for the internal environment of buildings and performance concepts.     

Water crossings — the options

Water in the shape of rivers, lakes, fjords, oceans and so on, sometimes seems to provide a barrier to improving the environment and preventing further development. Hitherto unconsidered options may be available to cross over or under a water barrier. Without full knowledge of the available possibilities, planners and decision-makers are not able to make the best-informed choices. This paper initially examines the relative attributes of bridges, ferries, submerged floating tunnels, immersed tunnels, soft ground tunnels and rock tunnels. Reasons for selection or rejection of each option are discussed. The paper goes on to introduce immersed and floating tunnels in more detail. Specific examples are given to convey the concepts.     

某医院新建综合住院大楼深基坑支护设计

以某医院新建综合住院大楼基坑支护设计为例,依据相关规范及该场区自然条件,采用了钢管内支撑基坑支护形式,结果表明该设计方案可提高整个体系刚度及有效控制基坑变形,取得了良好效果。     

大国重器节能先锋--徐工集团2014道路机械新品发布荣耀启航

徐工道路机械事业部“大国重器节能先锋--徐工集团2014道路机械新品发布”2月22日在徐州荣耀启航,作为全国发布的第一站,来自徐州及周边的200余名用户共同见证了此次盛会。这也是徐工道路继2014“先进可靠节能高效”成套新产品全球发布,在节能技术取得创新突破后,瞄准市场最前沿,所开展一次全国性的新品发布。     

Urban renewal on the last frontier

After the Alaskan earthquake of 1964, the frontier fishing village of Seldovia was threatened by high tides along its picturesque downtown waterfront. The availability of federal reconstruction funds lured policy makers to opt for urban renewal rather than rehabilitation. The result was an economic, social and aesthetic disaster. The episode illustrates some of the difficulties of environmental management on the last U.S. frontier.     

Tunnels in Opalinus Clayshale — A review of case histories and new developments

Numerous tunnels have been built and new tunnels are planned in the Swiss Jura Mountains, and most of them intersect Opalinus Clayshale. This paper reviews several tunnel case histories which show that Opalinus Clayshale can be quite problematic by swelling during construction and also during operation, if the invert cover is not strong enough and if water can penetrate into the shale. Modern testing methods and a newly developed behavioral model based on these tests are then presented. They clearly show that Opalinus Clayshale when unloaded as can occur around the tunnel perimeter swells which in turn can induce creep and even failure. Considering this behavior in design and construction will reduce swelling and creep. Modern, TBM-based tunnel construction which utilizes prefabricated liner elements satisfies these requirements. In addition, the paper describes project management procedures that allow one to include the risks associated with swelling when assessing and awarding bids.     

Development of new Los Angeles seismic analysis criteria for tall buildings—site-specific considerations

Many tall buildings are planned and constructed in the city of Los Angeles. Significant building code changes as a result of recent earthquakes will complicate the design and plan checking for new buildings, not only in Los Angeles, but throughout all seismic regions in the United States and around the world. This paper reports on new efforts to develop seismic analysis criteria for Los Angeles. The initial efforts have been in the areas of the design basis ground motions, near-source effects on ground motions and building design, and the first yield limit state. A study of the design basis ground motions in the Los Angeles area indicates that the present code-defined level of ground motion may underestimate the seismic forces in design. Near-source effects would affect practically all of the heavily populated and built-up portions of Los Angeles due to the many known and suspected active seismic sources in the region. Studies of the group motions suggest that a return period of about 40 years may be reasonable to estimate the earthquake demand for the first yield limit state.     

Model tests on peat — Geotextile — Lightweight aggregate system

Considerable research has been done in recent years dealing with the interaction of normal weight aggregate and geotextiles overlying soft compressible soils. In some instances, lightweight aggregate is used instead of normal weight aggregate to reduce settlements, and in the bridge abutment areas, to minimize lateral forces and to reduce drag loads on piles. However when used with geotextiles, it is not known whether the overall roadbed stiffness is affected when lightweight aggregate is used in place of normal weight fill. This paper reports the results of experimental research dealing with interaction of lightweight aggregate and geotextiles overlying peat subgrades. Variables investigated in the present study are: differing aggregate types and densities, thickness of the aggregate layer and geotextile types. The results indicate that the overall roadbed stiffness is unaffected when lightweight aggregate is used instead of normal weight aggregate, for small deflections and initial load application.     

Concrete — moisture

Engineer research associate Hiroshi Hashida of the Tokyo Institute of Technology and co-authors Kyouji Tanaka and Michio Koike present test results on moisture redistribution in concrete which will help practitioners to understand and overcome the problems this causes in applied finishes.