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This paper presents the results from a prediction event, organized by the University of Western Australia (UWA) and the National Geotechnical Centrifuge Facility (NGCF), and performed as part of the International Symposium on Frontiers in Offshore Geotechnics to assess uncertainty in predicting the monotonic and cyclic lateral response of conductors. Geotechnical professionals from around the world were invited to predict the response of a model conductor (a flexible pile) subjected to a series of loading sequences in a centrifuge. A normally consolidated fine-grained soil was used in the tests, which was characterized by soil elements and in-flight T-bar penetrometer testing. While some participants provided accurate predictions, the mean response was an overestimate of the monotonic and cyclic load at the pile head, which was significant for large and very small displacements. An analysis of the submissions is presented to quantify the variability of the predictions received, assess the consequences of each design, and relay the uncertainty associated with engineering judgment in design. [ABSTRACT FROM AUTHOR]

This paper presents results of transdisciplinary research on the development of a bioinspired computational framework for engineering design. This framework is intended to support design by addressing three critical design objectives, including novelty, optimality, and robustness. It provides several computational models and methods, which are inspired by fundamental processes occurring in nature, and discusses their potential for enhancing design. They include models and methods for evolutionary, developmental, and coevolutionary design. Their use is illustrated with examples from the area of steel structural design ranging from a simple cantilever beam design problem to a much more complex problem of designing wind bracings in tall buildings. The paper also shows how several methods and models can be integrated and form a coherent bioinspired computational framework for engineering design. [ABSTRACT FROM AUTHOR]

Improving and supporting the process of design knowledge reuse in engineering design can increase productivity, improve the quality of designs, and lead to greater corporate competitive advantage. Whereas internal knowledge reuse from one’s personal experiences is very effective, external knowledge reuse from an external digital or paper archive often fails. Based on a formalization of the internal reuse process from ethnographic studies, a prototype system, CoMem (corporate memory) is presented, which supports the reuse process, particularly the steps of finding and understanding. This paper presents a usability testing framework and methodology for the evaluation of reuse systems such as CoMem. The two pertinent variables are (1) the type of finding task; and (2) the size of the repository. Preliminary results from the evaluation of CoMem are presented as an example of the application of this framework for studying and assessing corporate memory design reuse systems. [ABSTRACT FROM AUTHOR]

Computer support for conceptual design of building structures is still ineffective, mainly because existing structural engineering applications fail to recognize that structural design and architectural design are highly interdependent processes. This paper describes a computer representation called StAr (structure-architecture), aimed to act as a common basis for collaboration between architects and engineers during conceptual structural design. The StAr representation describes the structural system as a hierarchy of entities with architectural counterparts, which enables the direct integration of the structural system to the building architecture as well as engineering feedbacks to the architect at various abstraction levels. The hierarchical structural description implements a top-down design approach where high-level structural entities, which are defined first, facilitate the configuration of lower-level entities whose functions in turn contribute to those of the higher-level wholes that they belong to. The representation has been built on top of a geometric modeling kernel that allows reasoning based on the geometry and topology of the design model, which is paramount during early design stages. A proof-of-concept software prototype, called StAr prototype, has been developed and a test example demonstrates how the representation can support the different activities that take place during the conceptual design of building structures. [ABSTRACT FROM AUTHOR]

This paper presents a new model for analyzing a nonlinear soil–pile interaction subject to horizontal shaking of a vertical circular pile embedded in a soil layer of finite thickness. The pile rests on bedrock with either a pinned or a clamped support. The soil mass is assumed composing of a “semi-nonlinear” inner soil zone around the pile and a linear viscoelastic soil zone outside the inner zone. When the inner soil behaves linearly, the present solutions are identical to those obtained by Nogami and Novak in 1977. Numerical results show that soil resistance of less slender piles developed against the vibration is larger than that of more slender piles. Soil resistance depends more strongly on the size of the nonlinear inner zone when the pile is vibrating at a frequency higher than the natural frequency of the soil. Soil nonlinearity, in general, results in a smaller damping and stiffness of the soil–pile system, except at high frequency. At higher vibration frequency, the situation can be very complicated. The exact value of the dynamic stiffness of the soil–pile system depends on elastic shear wave speed, soil nonlinearity, vibration frequency, slenderness ratio of the pile, magnitude of vibration, and tip conditions of the pile. Generally speaking, the dynamic stiffness is smaller than the static stiffness. The normalized dynamic stiffness for pile with a pinned tip is, in general, larger than that with a clamped tip, while the reverse is true for the damping. [ABSTRACT FROM AUTHOR]

Geology and related earth processes are an inherent part of civil engineering design and construction. This paper examines eight specific examples to illustrate how geologic factors can dominate project behavior. The examples are from a spectrum of environments associated with design and construction of roads and airfields and vary from the apparently obvious to the more subtle. Failure to understand the geologic conditions at a site almost invariably results in unsatisfactory performance. This complex interplay between geology and engineering is at the heart of the geotechnical profession and should be appreciated by all. [ABSTRACT FROM AUTHOR]

In this paper, we present a two-scale numerical method in which structures made up of composite materials are simulated. The method proposed lies within the context of homogenization theory and assumes the periodicity of the internal structure of the material. The problem is divided into two scales of different orders of magnitude: A macroscopic scale in which the body and structure of the composite material is simulated, and a microscopic scale in which an elemental volume called a “cell” simulates the material. In this work, the homogenized strain tensor is related to the transformation of the periodicity vectors. The problem of composite materials is posed as a coupled, two-scale problem, in which the constitutive equation of the composite material becomes the solution of the boundary-value problem in the cell domain. Solving various examples found in the bibliography on this subject demonstrates the validity of the method. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the behavior of elastic–plastic specimens during testing in a triaxial apparatus. In particular, an investigation of the influence of a number of imperfections on the observed behavior of a specimen is performed. To this end, we present influences of end platen friction, end platen inclinations, and the shape of specimen on what we broadly understand by “constitutive behavior.” We investigate the issues related to the constitutive as opposed to boundary value behavior or elastic–plastic specimens. We present a number of examples to illustrate the differences between different types of response, which are usually, and wrongly, just called the constitutive behavior. [ABSTRACT FROM AUTHOR]