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The economic design of the slabs is the most influential on the construction cost and choosing the appropriate system is the key to the slabs optimal design, and there are many systems that have been developed recently to reach the most economical design. In this research, we try to mix two systems, each of them has its optimal use, and each of them has its advantages and limits for uses, and they have been mixed to try to find a dual system with more advantages. This paper presents a slab system consisting of flat slab system that its field strip areas were replaced with two-way hollow block systems. Consequently, the total weight of the resulting slab was reduced, which positively affected the quantities of steel reinforcement used directly, in addition to its reflection on the design of columns and foundations due to the low self-weight of the slabs. The validity of the proposed concept has been verified through a finite element analysis using Program SAP2000 that was applied to several cases with different configurations under static and dynamic loadings.

The range of functions and the expectations of the users of flooring systems indicate that apart from purely construction-related (i.e. general construction) characteristics, floors used as partition elements have the potential to meet various customer needs on the construction market. Therefore, they constitute interesting research material not only for specialists in the building sector, but also for economists. The aim of this article is to present the results of a survey of the determinants of selection of flooring systems, the popularity of the specific systems on the Polish market, as well as to present the customer needs map as a universal tool in the customer service process on the example of flooring systems. The paper was prepared on the basis of the available literature, as well as the quantitative research carried out in the period from September 2015 to February 2016. The research results indicate that the influential factors taken into consideration in the process of selection of a given flooring system are construction parameters, the speed of assembly and the final cost. Among the key technical parameters influencing customers’ decisions one may list noise insulation, thermal insulation and lower surface finishing. In Poland, monolithic and multi-rib beam-and-block (Teriva-type) flooring systems prevail. Based on the factors and criteria set out in the survey, a special map of customer needs relevant for the process of selection of a flooring system has been created. Among other purposes, the map is supposed to enable more profound relation with customers, individualization, streamlining and unification of the customer service process, as well as better understanding of their needs.

The study investigates the economics of rearing goats for short period under different rearing system viz. rearing on PVC slatted floor, concrete slatted floor and wooden slatted floor. The net income and benefit cost ratio was high when the returns was calculated from the sale of kids. Rearing of animals up to six months for meat is also economic but the profit margin is less compared to sale of kids. In the current study, it was observed that animals reared on PVC floor fetched the highest benefit cost ratio in terms of sale of kids or meat. The net income from a single kid in the current study varied from Rs. 893.81 (PVC floor), followed by (760.03) wooden floor and 703.41(concrete floor) when the animals were reared for meat. While when the kids were sold, the net income from PVC floor was Rs. 2118.31, that of concrete floor was\ Rs.1999.41 and wooden floor was Rs.1653.03. The benefit cost ratio was highest when the animals were reared for meat ie., in PVC group it was 1.40 followed by wooden group (1.35) and finally the concrete group (1.32). When the animal were sold at six months the benefit cost ratio varied from 1.96 in PVC floor, 1.91 in concrete floor and 1.75 in wooden floor.

Comfort and habitability are requirements for housing quality, affected by underfloor system. Thus, this study aims to design lightweight concrete slabs underfloor with the use of ethylene vinyl acetate (EVA) aggregates, with two grain sizes of conventional aggregates replaced with EVA. The experimental counted on four unit mixes, varying the ratio between EVA coarse and fine aggregates and natural aggregates. The underfloor plates were molded with thickness of 3, 5 and 7 centimeters, and 3cm plus 1cm of conventional coating. Slabs were submitted to specific mass and standardized impact sound pressure level tests. Results showed a correlation between specific masses and impact sound values, being that 7cm thickness slabs with smaller specific mass, with total aggregate replacement, presented noise intensity reductions of 17dB in comparison to same thickness slabs with natural sand and smaller content of EVA coarse aggregate; and a 28dB reduction in relation to the slab without underfloor.

Composite slab consisting of in‐situ casted reinforced concrete on profiled sheeting, which is connected to steel beams by shear connectors, is a common structural flooring system in office buildings and car parks. The headed welded studs are inexpensive and rather easy to use in‐situ because they can be welded to the steel beam through the metal sheeting. A permanent link is created between the composite slab and steel beams leading to rather time‐consuming and expensive deconstruction process. Various types of bolted shear connections, recently investigated by various researchers in Europe, Australia, USA, provide a demountable alternative for the flooring system. This paper describes the experimental study using a bolted shear connector consisting of an embedded bolt/coupler and external bolt, originally developed for a prefabricated concrete deck. A full‐scale composite beam was tested under working loads up to 6.25kN/m2 in a 4‐point bending. In addition to bolted shear connectors a timber joist is embedded in the composite slab over the web of the steel beam. After the first life cycle, the timber joist provides the cut edge of the slab. The experiment is used to model behaviour in the first life cycle. The composite slab was then cut, demounted, re‐assembled and tested again in the second life cycle. The load was applied up to 6.25kN/m2 and finally to the failure. Multiple arrangements of shear connectors were investigated to analyse performance of "a modified composite slab". Experience gained on the experiments of testing the composite beam in the first and the second life cycle is accompanied by FE analysis. [ABSTRACT FROM AUTHOR]

The treatment of cold-formed steel sections in design codes is very largely restricted to individual members under ideal conditions. More efficient design is possible if the complexities of the structural response caused by the thin plating and complex shapes, together with the actual conditions of load introduction and restraint arising from practical situations can be recognised. Traditionally this has only been possible by resorting to full-scale testing. This is, of course, time consuming and expensive; moreover, the impossibility of covering all variations of all the important problem parameters means that developing a comprehensive understanding of all aspects of the physical behaviour is unlikely. Numerical analysis offers the promise of an alternative approach. However, for this to be reliable there must be confidence that it accurately models the physical situation. For the past decade a programme of research has been underway aimed at the provision of a more complete understanding of the structural behaviour of cold-formed steel sections when employed in particular practical situations. Three such cases are addressed herein: purlins as used in the roofs of industrial buildings, beams used to support floors and columns forming part of a stud wall framing system. In each case the process has been to firstly identify all the important structural components including fastening arrangements, then to develop numerical models using ABAQUS that represent each of these physical features to a sufficient degree of accuracy, then to validate the models by comparison with all available test data, then to conduct parametric studies covering the full range of variables found in practice and, finally, to use the pool of results and the improved insights into behaviour as the basis for improved design approaches that, by more accurately capturing the key physical features, provide better predictions of performance. An important feature of this has been to ensure that the resulting design procedures were the simplest possible consistent with reliable predictions. • Simulation and design techniques for cold-formed steel purlin, floor and stud wall systems are presented. • Challenges encountered in modelling the contributions of the key system components are described and solutions are presented. • Validation of the developed FE models against physical tests reported in the literature is presented. • Parametric studies covering the full range of variables found in practice are described. • Design recommendations harnessing the beneficial interaction between all system components are made. [ABSTRACT FROM AUTHOR]

This paper presents the fire resistance behaviour of partially encased in concrete ultra shallow floor beams (USFB) using numerical analysis method based on material specifications of the EN1994-1-2. Investigating the behaviour of USFBs under elevated temperatures is crucial in determining their fire resistance and evaluating their overall performance in contemporary construction. Even though the manufacturing company provides fire resistances for USFBs based on EC4-1-2 procedures, their response to elevated temperature effects remains up to date neither well documented nor clearly understood. The analyses involved two different beams of span 5 m and 8 m respectively, as specified by the manufacturer. Analysis results showed that such beams, when unprotected, experience severe temperature gradients if exposed to fire, as the lower flange still remains unprotected in contrast to the concrete encased part of the cross-section. As it was anticipated, the moment capacity governs the fire resistance of the beams and the load factor highly effects the elevated temperature behaviour. In addition, the loss of the lower flange, which develops high temperatures, is not compensated by the web and consequently the moment capacity ultimately depends on the temperature of the lower flange. Results also suggest that simulated beams sustained the applied load for approximately 40 min of exposure to the standard fire. [ABSTRACT FROM AUTHOR]

An experimental investigation has been conducted into the degree of shear interaction between cold-formed steel floor joists and wood-based flooring panels and the resulting benefits derived in terms of composite action. A series of four-point bending tests have been carried out to evaluate the overall system behavior, while material tests have been performed to accurately define the material properties of each component of the examined system. Two different shear transfer mechanisms were examined: self-drilling screws with varying spacing and structural adhesive. The bare system was also tested to provide a reference response, against which the stiffness and capacity of the composite system could be bench-marked. The experiments showed that significant benefit could be derived as a result of composite action with as much as a 100% increase in bending capacity and 42% increase in stiffness. [ABSTRACT FROM AUTHOR]