Challenges of Structure in Today＇s Architectural,Economic and Social Context

The recent establishment of a digital culture and society, together with current financial crisis and urgent energetic and climatic needs, has radically changed the architectural scene from the optimism of some years ago to a situation of uncertainty and huge social demands and challenges. In this context, it is suggested to rethink the role of structure in architecture, such as an enabler, a guide and a catalyst. The purpose of this paper is to present the economic, cultural and social context in which architecture develops nowadays. The method, to suggest a discussion on which role the structure may adopt in the architecture to come. The achievement, to highlight its potential to face current requirements and challenges.     

Planning and Construction of Low Carbon Cities:The Relevance of Cost-Benefit Analysis

Cities are the major source of carbon dioxide emissions in China,and are the critical locations where emissions should be effectively managed.Adopting a low carbon urban development model is the pathway towards reducing the emissions.A low carbon city development model means achieving efficient and effective urban growth through low energy consumption and low emissions.While many local authorities in China have started to express the intention to construct low carbon cities,it is important to emphasize the need to apply a Cost-Benefit Analysis (CBA) to low carbon urban policies and development projects.Since all policies and projects will have their costs and benefits to the society,the effects of the policies and projects on reducing emissions should be measured and assessed objectively.Through the setting up of an analysis framework to assess the costs and benefits,one can provide a scientific basis for decision making,and enhance the overall efficiency in the use of resources for the society as a whole.     

A study of jacking force for a curved pipejacking

For a pipejacking, the jacking force is critical to balance the resistance force and to move the pipe string forwards. The driving mechanism of a curved pipejacking is more complicated than a straight-line pipejacking, and its jacking force is also more difficult to be determined. The paper theoretically studies the jacking force of a curved pipejacking by considering the static equilibrium of earth pressure, resistance at cutting face, friction at pipe surface, and the driving force behind the pipe string. The derived theoretical formula can be used to estimate the driving forces of a straight-line or a curved pipejacking. Case study was performed by applying the theoretical and empirical formulae. After calibration, the corrected formula is more accurate and more applicable.     

The Planning of Shanghai Yuyuan Tourist and Shopping Center

Shanghai Yuyuan Tourist and Shopping Center is tobe located to the west of a classical garden,Yuyuan and theold Temple of the City God,and to the south of theYuyuan Bazaar,covering about 2 hectares.The northernpart of the site is the old bazaar and the southern part a resi-dential quarter.It is planned that they are to be rebuilt intothe Yuyuan Tourist and shopping Center.(Fig.1) The Yuyuan garden and the old Temple are historicsites and the Yuyuan Bazaar a traditional market in the oldcity of Shanghai.They are fairly well preserved.Facing thereconstruction project of this area,how to maintain and in-herit the tradition has become the main theme in the plan-ning of the Yuyuan Tourist and Shopping Center. We deem that the preservation of the tradition is ofgreat importance in both culture and economy.Thereforewhile planning the Center,we have made a preliminary     

Ground reaction curves for circular excavations in non-homogeneous,axisymmetric strain-softening rock masses

Fast methods to solve the unloading problem of a cylindrical cavity or tunnel excavated in elasto-perfectly plastic, elasto-brittle or strain-softening materials under a hydrostatic stress feld can be derived based on the self-similarity of the solution. As a consequence, they only apply when the rock mass is homogeneous and so exclude many cases of practical interest. We describe a robust and fast numerical technique that solves the tunnel unloading problem and estimates the ground reaction curve for a cylindrical cavity excavated in a rock mass with properties depending on the radial coordinate, where the solution is no longer self-similar. The solution is based on a continuation-like approach(associated with the unloading and with the incremental formulation of the elasto-plastic behavior), fnite element spatial discretization and a combination of explicit sub-stepping schemes and implicit techniques to integrate the constitutive law, so as to tackle the diffculties associated with both strong strain-softening and elasto-brittle behaviors. The developed algorithm is used for two practical ground reaction curve computation applications. The frst application refers to a tunnel surrounded by an aureole of material damaged by blasting and the second to a tunnel surrounded by a ring-like zone of reinforced(rock-bolted) material.     

Early Building Design:Informed decision-making by exploring multidimensional design space using sensitivity analysis

This paper describes a novel approach to explore a multidimensional design space and guide multi-actor decision making in the design of sustainable buildings.The aim is to provide proactive and holistic guidance of the design team.We propose to perform exhaustive Monte Carlo simulations in an iterative design approach that consists of tw o steps:1) preparation by the modeler,and 2) a multi-collaborator meeting.In the preparation phase,the simulation modeler performs Morris sensitivity analysis to fixate insignificant model inputs and to identify non-linearity and interaction effects.Next,a representation of the global design space is obtained from thousands of simulations using low-discrepancysequences(LPτ) for sampling.From these simulations,the modeler constructs fast metamodels and performs quantitative sensitivity analysis.During the meeting,the design team explores the global design space by filtering the thousands of simulations.Variable filter criteria are easily applied using an interactive parallel coordinate plot w hich provide immediate feedback on requirements and design choices.Sensitivity measures and metamodels show the combined effects of changing a single input and how to remedy unw anted output changes.The proposed methodology has been developed and tested through real building cases using a normative model to assess energy demand,thermal comfort,and daylight.     

The coal cleat system： A new approach to its study

After a general analysis regarding the concept of coal ＂cleat system＂, its genetic origin and practical applications to coalbed methane （CBM） commercial production and to C02 geological sequestration projects, the authors have developed a method to answer, quickly and accurately in accordance with the industrial practice and needs, the following yet unanswered questions： （1） how to define the spatial orientation of the different classes of cleats presented in a coal seam and （2） how to determine the frequency of their connectivites. The new available and presented techniques to answer these questions have a strong computer based tool （geographic information system, GIS）, able to build a complete georeferentiated database, which will allow to three-dimensionally locate the laboratory samples in the coalfield. It will also allow to better understand the coal cleat system and consequently to recognize the best pathways to gas flow through the coal seam. Such knowledge is considered crucial for understanding what is likely to be the most efficient opening of cleat network, then allowing the injection with the right spatial orientation, of pressurized fluids in order to directly drain the maximum amount of gas flow to a CBM exploitation well. The method is also applicable to the CO2 geological sequestration technologies and operations corresponding to the injection of CO2 sequestered from industrial plants in coal seams of abandoned coal mines or deep coal seams.     

Numerical modeling for rockbursts: A state-of-the-art review

As the depth of excavation increases,rockburst becomes one of the most serious geological hazards damaging equipment and facilities and even causing fatalities in mining and civil engineering.This has forced researchers worldwide to identify different methods to investigate rockburst-related problems.However,some problems,such as the mechanisms and the prediction of rockbursts,continue to be studied because rockburst is a very complicated phenomenon influenced by the uncertainty and complexity in geological conditions,in situ stresses,induced stresses,etc.Numerical modeling is a widely used method for investigating rockbursts.To date,great achievements have been made owing to the rapid development of information technology(IT)and computer equipment.Hence,it is necessary and meaningful to conduct a review of the current state of the studies for rockburst numerical modeling.In this paper,the categories and the origin of different numerical approaches employed in modeling rockbursts are reviewed and the current usage of various numerical modeling approaches is investigated by a literature research.Later,a state-of-the-art review is implemented to investigate the application of numerical modeling in the mechanism study,and prediction and prevention of rockbursts.The main achievements and problems are highlighted.Finally,this paper discusses the limitations and the future research of numerical modeling for rockbursts.An approach is proposed to provide researchers with a systematic and reasonable numerical modeling framework.     

Integrated optimisation of photovoltaic and battery storage systems for UK commercial buildings

Decarbonising the built environment cost-effectively is a complex challenge public and private organisations are facing in their effort to tackle climate change.In this context,this work presents an integrated Technology Selection and Operation(TSO)optimisation model for distributed energy systems in commercial buildings.The purpose of the model is to simultaneously optimise the selection,capacity and operation of photovoltaic(PV)and battery systems;serving as a decision support framework for assessing technology investments.A steady-state mixed-integer linear programming(MILP)approach is employed to formulate the optimisation problem.The virtue of the TSO model comes from employing granular state-of-the-art datasets such as half-hourly electricity demands and prices,irradiance levels from weather stations,and technology databases;while also considering building specific attributes.Investment revenues are obtained from reducing grid electricity costs and providing fast-frequency response(FFR)ancillary services.A case study of a distribution centre in London,UK is showcased with the goal to identify which technologies can minimise total energy costs against a conventional system setup serving as a benchmark.Results indicate the best technology configuration is a combination of lithium-ion batteries and mono-crystalline silicon PVs worth a total investment of ￡1.72 M.Due to the available space in the facility,the preferred PV capacity is 1.76 MW,while the battery system has a 1.06 MW power capacity and a 1.56 MWh energy capacity.Although PV performance varies across seasons,the solution indicates almost 30%of the energy used on-site can be supplied by PVs while achieving a carbon reduction of 26%.Nonetheless,PV and battery systems seem to be a questionable investment as the proposed solution has an 8-year payback,despite a 5-year NPV savings of ￡300k,implying there is still a performance gap for such systems to be massively deployed across the UK.Overall,the TSO model provides valuable insights into real-world project evaluation and can help to reduce the uncertainty associated with capital-intensive projects;hence proving to be a powerful modelling framework for distributed energy technology assessments.     

Refurbishing Faestningens Materialgard： A Heritage Complex

F estningens Materialgard is a listed complex located in downtown Copenhagen. The refurbishment of the listed complex was studied to provide knowledge on how a process for refurbishing heritage buildings can be carried out successfully, as refurbishment of heritage buildings is often a complicated process. The process shows how to choose, evaluate and implement measures creating synergy between the interests of preserving heritage values and to develop affordable refurbishment that meets the requirements for the future use of the building. The refurbishment followed included restoration, energy upgrading and refurbishment of the individual buildings that make up the listed complex. The process focuses on the cooperation and dialogue between the parties involved. F estningens Materialgard is a case study where the Heritage Agency, the Danish Working Environment Authority and the owner as a team cooperated in identifying feasible refurbishment measures. Through the process the owner was supported by architects and engineers. Focus is put on how, to identify potential energy savings and, to decide on energy upgrading measures when refurbishing and restoring listed buildings. The refurbished Faestningens Materialgard is visualized in photos.