Component Concept

Abstract: 1.Introduction Over the past few decades a number of studies have been made with respect to the modeling of cement hydration in order to grasp the timedependent behavior of cement-based materials[1-3]. In those recent studies, the simulation of intricate and compound processes of cement hydration, especially those focused on micro-mechanics, have utilized the potential of modern computers [4,5]. Two points seem to be helpful in attempting to sketch out what makes it complex to simulate the process of cement hydration and why it needs to be understood using a computer. One is physical aspect. Cement paste matrix, which is composed of cement particles and water is determined by both particle size distribution [1,3] and water-to-cement ratio [7]. In the cement hydration process, cement particles are interconnected and make the structure of the cement paste matrix. This physical aspect affects the rate of cement hydration through the diffusion of ions [3,5]. The second important variable is the poly-mineral material. Its components react with each other, and temperature has a great influence on the rate of hydration from a chemical point of view [2,6]. These two aspects have a mutually dependent relationship through diffusion of ions and water and material formation. This relationship cannot be solved with a simple equation. Using the power of computers, however, and the concept of discrete event system makes it possible to portray the cement hydration process. In this contribution, based on the Tomosawa’s model [8], model for cement paste matrix named ‘CCBM’ [Computational Cement Based Material Model] is proposed and its potential for portraying the concrete properties is discussed with experimental results.

Abstract: The paper describes the design considerations for modelling and simulation of mechatronic systems. The system is based on a component concept enabling the designer to pick component models that match the physical components of the setup to be modelled from a block library. Another important feature of the system is the ability to change the complexity of the simulation model in a simple, powerful and well structured way. This feature makes it simple for the designer to evaluate the influence of including different aspects of the components. The complexity can be changed both on the component level and for the whole model. This library that can be extended by the user contains standard components, such as DC-motors, potentiometers, encoders, pneumatic elements, and a Maple based facility to generate symbolic equations of motion. To evaluate the concepts the mechatronic Simulink library blockset has been implemented as a prototype based on MATLAB and Simulink and has been used to model several mechatronic systems. The library is presently being tested in different projects.