A fuzzy logic model to predict specific energy requirement for TBM performance prediction

Prediction of tunnel boring machine performance is a critical key for successful tunnel excavations. Specific energy requirement of disc cutters, which is defined as the amount of energy required to excavate a unit volume of rock, is one of the important parameters used for performance prediction of these machines. Much research has been conducted to predict cutting parameters of disc cutters using analytical, empirical and numerical approaches. In recent years alternative methods, such as fuzzy logic, have been extensively used to deal with subjects having ambiguities and uncertainties. In this study, a model was established to predict specific energy requirement of constant cross-section disc cutters in the rock cutting process by using fuzzy logic method. This model is based on experience and the database which consists of linear cutting test results that were generated over for many years at the Earth Mechanics Institute of the Colorado School of Mines. The model predicts specific energy requirements of disc cutters using uniaxial compressive and tensile strength of rocks, disc diameter and tip width, penetration and spacing of cuts.     

Application of several optimization techniques for estimating TBM advance rate in granitic rocks

This study aims to develop several optimization techniques for predicting advance rate of tunnel boring machine(TBM)in different weathered zones of granite.For this purpose,extensive field and laboratory studies have been conducted along the 12,649 m of the Pahang-Selangor raw water transfer tunnel in Malaysia.Rock properties consisting of uniaxial compressive strength(UCS),Brazilian tensile strength(BTS),rock mass rating(RMR),rock quality designation(RQD),quartz content(q)and weathered zone as well as machine specifications including thrust force and revolution per minute(RPM)were measured to establish comprehensive datasets for optimization.Accordingly,to estimate the advance rate of TBM,two new hybrid optimization techniques,i.e.an artificial neural network(ANN)combined with both imperialist competitive algorithm(ICA)and particle swarm optimization(PSO),were developed for mechanical tunneling in granitic rocks.Further,the new hybrid optimization techniques were compared and the best one was chosen among them to be used for practice.To evaluate the accuracy of the proposed models for both testing and training datasets,various statistical indices including coefficient of determination(R~2),root mean square error(RMSE)and variance account for(VAF)were utilized herein.The values of R~2,RMSE,and VAF ranged in 0.939-0.961,0.022-0.036,and 93.899-96.145,respectively,with the PSO-ANN hybrid technique demonstrating the best performance.It is concluded that both the optimization techniques,i.e.PSO-ANN and ICA-ANN,could be utilized for predicting the advance rate of TBMs;however,the PSO-ANN technique is superior.     

基于密实核理论的TBM盘形滚刀磨损预测模型研究

CCS(Constant Cross Section)盘形滚刀磨损是影响硬岩隧道掘进工作效率和成本预算的关键问题。根据CCS型滚刀的工作特点和岩石切割破碎原理,分析研究滚刀破碎岩石的复杂应力状态,建立了考虑密实核效应的滚刀破岩机理。通过推导密实核长度的理论解析式,获得了基于塑性去除磨粒磨损机制的滚刀磨损量与法向荷载之间的数学关系式,进而提出了滚刀磨损速率及切削寿命预测模型。基于此,分析计算了深圳地铁12号线某区间共757环的正面滚刀实测磨损数据,发现预测值与实测值的相对差异率值均小于10%,验证了预测模型的有效性。此外,通过与现有滚刀磨损预测模型对比分析,结果表明本文提出的预测模型计算结果更接近于现场实测值,说明了滚刀磨损速率和切削寿命指标可作为评价滚刀磨损特性的可靠指标,为TBM工程现场刀具更换方案设计提供更为合理可行的理论依据。     

基于免疫连续蚁群算法的岩土工程反分析研究

基于进化算法等全局优化算法的岩土工程优化反分析是解决实际问题的一种较好的思路,但计算效率是这类算法的最大问题。为了克服这种反分析方法的缺点,提高反分析的计算效率,首次把一种新型仿生算法——连续蚁群算法引入岩土工程领域。并为了更进一步提高算法的效率,把免疫原理引入连续蚁群算法,提出了免疫连续蚁群新算法。在此基础上,结合有限元数值分析技术,提出了一种新的岩土工程反分析算法——免疫连续蚁群算法反分析。最后,通过一个简单算例验证了该法的有效性及卓越的计算效率。     

Use of TBM muck as construction material

Tunnel boring machines (TBMís) are widely used in tunnel construction in rock. The rock chips (muck) produced are rarely used for construction applications, however, because the suitability of the material is not well understood. Yet the cuttings appear to be of approximately the correct average size for some applications. If they are suitable in other respects, cost savings can be realized in tunnel construction, where aggregate is a common requirement. A review of standard construction aggregate specifications indicates that hardrock TBM much would be suitable for several construction applications with a minimum of processing: road pavement and structural concrete. Processing options also are discussed for cases where the raw TBM muck is nearly, but not quite, suitable. A 0.65 metric ton (1420 lb) cutting sample generated by a laboratory tunnel boring machine operating in a welded tuff is analyzed for suitability for different construction applications. In addition, numerous tunneling projects that use or have studied TBM waste for construction purposes are described.     

Thinking with Matter

Mark West considers the qualities of the analogue against the digital in the context of his work at the Centre for Architectural Structures and Technology (CAST) at Manitoba. Unable to fault the computer's ability to provide complex calculations for the fabrication of forms, he insists that the fidelity and investigative potential that he has found in the reality of the physical model and hand-drafted drawing have yet to be surpassed. Copyright © 2008 John Wiley & Sons, Ltd.     

Material,Form and Force

Conventionally, material in architecture has been treated as the ‘servant’ of form. An iterative design process, though, that continuously integrates material, form and force has the potential to unfold a new generative logic of form-finding. This offers ways of processing the flow of forces through a material object and balancing variations of form with the organisation and behaviour of material. Toni Kotnik and Michael Weinstock present a series of experimental construction projects, developed within the Emergent Technologies and Design (EmTech) programme at the Architectural Association (AA) in London, that explore the intricate relationship between material, form and force. Copyright © 2012 John Wiley & Sons, Ltd.     

Structured Becoming: Evolutionary Processes in Design Engineering

Computational design techniques are changing the role of analysis tools in collaborations between architects and engineers. Digital feedback loops of synthesis, analysis and evaluation establish a ‘process of becoming’ in which structural solutions evolve and adapt to specific requirements. Highly differentiated constructions are possible when digital techniques are fully integrated in design and production. Klaus Bollinger, Manfred Grohmann and Oliver Tessmann discuss these novel paradigms in relation to recent projects from engineering office Bollinger + Grohmann. Copyright © 2010 John Wiley & Sons, Ltd.     

Aggregate Structures: Material and Machine Computation of Designed Granular Substances

In inanimate nature, large masses of granular substances are in constant processes of formation through perpetual cycles of erosion and accretion. What if architecture was to emulate this behaviour and allow for its own continuous reconfiguration? Karola Dierichs and Achim Menges establish the notion of an ‘aggregate architecture’. Composed of large numbers of unbound yet designed granules, aggregates are based on a fundamentally different logic of construction. In contrast to assembly systems, aggregates materially compute their overall constructional configuration and shape as spatiotemporal behavioural patterns, with an equal ability for both: the stable character of a solid material and the rapid reconfigurability of a fluid. Copyright © 2012 John Wiley & Sons, Ltd.     

Structural Stone Surfaces: New Compression Shells Inspired by the Past

Much of our architectural heritage today is built out of unreinforced masonry. It is often unclear why historic masonry structures still stand when conventional analysis tools have predicted their failure. In order to ensure the safety of these existing structures, there is an acute need for innovative tools that can accurately analyse their stability. Associate Professor Philippe Block, Tom Van Mele and Matthias Rippmann of the Block Research Group, part of the Institute of Technology in Architecture at ETH Zurich demonstrate how computational form-finding methods and design tools for masonry structures that stand in pure compression, such as arches and vaults, make it possible to design expressive and efficient surface structures that can be built with very little or low-quality material. By studying the techniques of medieval master builders, the Block Research Group has also developed new ways of building with masonry, enhanced by current construction and fabrication technologies. These new tools and reinvented construction methods can be applied in different contexts: for instance, by studying the structure of Gothic cathedrals, they manage to dramatically reduce the use of materials in office construction.     

Structuring Materiality: Design Fabrication of Heterogeneous Materials

What happens when we invert the usual sequence of the design process - form-structure-material - so materiality becomes the generative driver? Taking nature as her model, Neri Oxman advocates a new material method, Variable Property Design (VPD), in which material assemblies are modelled, simulated and fabricated with varying properties in order to correspond with multiple and continuously shifting functional constraints. Copyright © 2010 John Wiley & Sons, Ltd.     

Figures in the Sand

Coastal regions have become a magnet for recent development and globalisation, most conspicuously with the artificial islands off Dubai. This is a trend that has been offset by natural disasters, such as the tsunami and Hurricane Katrina. Christopher Hight and Michael Robinson describe how the Last Resort design studio at Rice School of Architecture has made its research focus Galveston Island, a nexus of natural, cultural and economic forces. Copyright © 2010 John Wiley & Sons, Ltd.     

The Tree Canopy as Blueprint

As the opportunities for new territories become more limited, the only way is up. Mitchell Schwarzer explores the dizzying heights of the ‘last biotic frontier’ of arboreal architecture with its high platforms, walkways and canopy craft. Challenging in construction and engineering terms, the tree canopy also requires engaging with a different atmospheric and climatic range to those conditions encountered at ground level. Copyright © 2010 John Wiley & Sons, Ltd.     

Otherwise Engaged: New Projects in Interactive Design

What are the possibilities of interactive technologies delivering a new level of social engagement in architecture? Taking 2002, with the ETH Ada project and Diller & Scofidio's Braincoat project, as an important watershed, Mark Garcia reviews the advances that have been made per se, and with four projects in particular, in socially interactive spatial design. Copyright © 2007 John Wiley & Sons, Ltd.     

Distinguishing Concepts: Lexicons of Interactive Art and Architecture

Interactive design has come about as a result of the intermingling of disciplines. As a consequence, the language it uses has become blurred - borrowed or stolen with little restraint from elsewhere. Though particular terms have become ubiquitous, the original concepts that lie behind them have been lost. This means that all too frequently they are no longer knowingly used. Usman Haque sorts the wheat from the chaff and brings clarity to bear on the vocabulary and thinking behind interactivity. Copyright © 2007 John Wiley & Sons, Ltd.     

Cross the River by Touching the Stones: Chinese Architecture and Political Economy in the Reform Era: 1978-2008

China's Open Door Policy and economic development set in motion in 1978 can be regarded as the triumph of pragmatism over theory - specifically Chairman Mao's brand of Marxist theory. Tao Zhu traces the progress of reform over the last 30 years, and its impact on Chinese architectural culture. Copyright © 2009 John Wiley & Sons, Ltd.