Applied Mechanics and Materials Vol. 796

Abstract: This work will present the students project, which is being investigated by the authors and which has direct connection with the dissertations of two of them. In their work, the authors deal with the topic of standardization of time and cost estimating in construction industry. The result of the project will be a software application that can model chosen activities during a construction and process and analyse obtained data. The work will introduce activities that have been chosen as the most suitable for examining, and it will be explained why they have been chosen. The work will describe suggested approaches for measuring and calculation of the time spent on individual activities during a construction and for cost estimation. It will also deal with circumstances influencing the duration and there will be explained how useful can be risk analysis when estimating durations of activities. The conclusion will summarize results of the work and it will outline future development and planned progress.

Abstract: The article describes the characteristics of a selected cement based materials and the possibilities of their use for critical infrastructure protection. The material properties were studied during field tests on slabs made from different materials – plain concrete, fibre reinforced concrete and high performance fibre reinforced concrete. In the article there are also presented lessons-learned of the research team of the military structures laboratory, which is run by the Department of Engineer Technologies at the University of Defence.

Abstract: The population explosion has lead to a markedly increased exploitation of our natural environment, hence the expression „sustainable development“ has become a catch phrase. In a historical perspective ecological problems recently became acute and this is why it is necessary to act quickly. It is obvious that we have to pay extreme attention to how we treat our environment and our sources. This necessarily will be reflected in the actions of the lawmakers in the future, and for the building industry the results will be that the authorities will enforce new law and regulations with direct consequences for the choice of materials and building techniques. There will be developed a set of standards dealing with environmental matters, putting limitations especially on the consumption of natural resources. Some countries already has standards dealing with various ecological aspects, like recirculation, down cycling, etc. The customers will prefer building products and systems that can document compliance with environmental attitudes. For all activities the environmental burden will be evaluated and limited by laws and regulations. Consequently the industry’s accountability for the environment will be a prerequisite for remaining in business.

Abstract: This article describes the proposal for subcontractor evaluation methodology after the realisation phase of a construction project. It deals with the importance and benefits of this evaluation for construction companies. The article includes a draft of the subcontractors' database – as a source of information for the subcontractor tender. The described proposal for evaluation will serve as the basis for the design of the software application which is mentioned in the conclusion. The described application will accelerate and automate the subcontractors' evaluation process and will form the basis for the development of other follow-up systems for subcontract management and control. The result of the proposed evaluation is exact (quantified) and therefore suitable for direct application in a multi-criteria evaluation of subcontractors' offers.

Abstract: The article describes the use of ultrasonic testing methods for examining slabs made from cement based materials. For the detection of cracks, in full-scale slabs before and after the explosion, ultrasonic pulse method was used. Data obtained before the explosion confirm the high quality of the cement based material. Another set of data taken after the explosion shows the scale of cracks in the slabs. The article compares material characteristics of the unreinforced concrete, steel fibre concrete and high performance fibre reinforced concrete on the basis of materials tested by using the passage ultrasonic method after the explosion.

Abstract: Many planners and clients (prospective building owners) are not sufficiently prepared for the building renovation. This reorientation calls for new means of help and abilities. A special importance belongs in this respect to the rating of the existing building substance (building stock). A sufficient reason to develop a new method for this purpose deliberately. The Rough Diagnosis of the building provides the picture of the building condition and of the costs for the repair of defects. The division of the building into Rough Diagnosis Elements improves the overview of the building condition and suggestions for measures. These measures can be compared in a transparent manner and related to individual stages. These pieces of knowledge facilitate the clear guidelines for project elaboration and costs, cut out according to needs and possibilities of the customer.