Archives of Civil Engineering

The reverse bending and straightening test is conducted on wires used for civil engineering applications to detect laminations which can pose a threat to the integrity of the wires. The FE simulations of the reverse bending and straightening of wires with laminations revealed that the reverse bending and straightening test is only effective in revealing or detecting near-surface laminations with lengths from 25 mm located up to 30% of the wire’s thickness and may not be an effective test to detect mid-thickness, near-mid-thickness, and short near-surface laminations with lengths below 15 mm. This is because wires with mid-thickness, near-mid-thickness and short near-surface laminations will pass through the reverse bending and straightening procedures without fracturing and therefore mid-thickness, near-mid-thickness and short near-surface laminations may go undetected. Consequently, other in-line non destructive testing methods might have to be used to detect mid-thickness, near-mid-thickness and short near-surface laminations in the wires.

The basis for calculating of resistance of welded RHS connections is provided by codes and international guidebooks. In the matter of calculation of the resistance of welded joints, the European standard contains very general recommendations without specifying the detailed calculation procedures, which (the) designers could use in their work. Estimation of resistance of welded semi-rigid joints is a complex issue because it requires determining of effective lengths of welds, their placement on the member walls with their different rigidity, and distribution of components of the load acting on each section of welds in various joint areas. In this paper an approximate assessment is suggested of the resistance of the welded connection in the overlapped K type joints, made of rectangular hollow sections.

The mechanical characteristics of the railway superstructure are related to the properties of the ballast, and especially to the particle size distribution of its grains. Under the constant stress-strain of carriages, the ballast can deteriorate over time, and consequently it should properly be monitored for safety reasons. The equipment which currently monitors the railway superstructure (like the Italian diagnostic train Archimede) do not make any “quantitative” evaluation of the ballast. The aim of this paper is therefore to propose a new methodology for extracting railway ballast particle size distribution by means of the image processing technique. The procedure has been tested on a regularly operating Italian railway line and the results have been compared with those obtained from laboratory experiments, thus assessing how effective is the methodology which could potentially be implemented also in diagnostic trains in the near future.

In this paper, transient analysis on heat transfer across the residential building roof having various materials like wood wool, phase change material and weathering tile is performed by numerical simulation technique. 2-dimensional roof model is created, checked for grid independency and validated with the experimental results. Three different roof structures are included in this study namely roof with (i). Concrete and weathering tile, (ii). Concrete, phase change material and weathering tile and (iii). Concrete, phase change material, wood wool and weathering tile. Roof type 3 restricts 13% of heat entering the room in comparison with roof having only concrete and weathering tile. Also the effect of various roof layers’ thickness in the roof type 3 is investigated and identifi ed that the wood wool plays the major role in arresting the entry of heat in to the room. The average reduction of heat is about 10% for an increase of a unit thickness of wood wool layer.

Investor bears responsibility for proper preparation of the investment process. One of his tasks is to prepare the project documentation and obtaina building permit. Frequently, during his work, there are situations and events whose im pact interferes with the design solutions. Regardless of reasons, alterations to a project constitute a source of cost risk. In each case, the Investor should be prepared for this type of a risk. Exposure to risk should be taken into account in the planning stage of the investment. Also, a model of investment execution should be chosen at this stage. The type of model is associated with the distribution of risk throughout the project. The aim of this paper is to identify events that generate risk related to alterations to Project Documentation in the context of the selection of the investment executionmodel.

This paper presents numerical simulationsof the behavior of a sandy layer subjected to a cyclic horizontal acceleration in shaking table tests, with a particular attention focused on the settlements of a dry sand layer, and on the liquefaction of saturated sand. A compaction/liquefaction model (C/L) is applied to these simulations. The infl uence of specifi c parameters of the model on the compaction and liquefaction of a sandy layer is shown and discussed. The results of simulations are compared with selected experimental data.

The article aims to evaluate the Portuguese building stock energy policies and strategy for energy saving in buildings among the EU members. It was found out the average heat transfer coefficients of the main structural elements of Portuguese Buildings and analyzed the U-values of this elements considering different time periods.

The fundamentals of this study were funded by the Agency for Development and Innovation (ADI) and co-financed by the European Regional Development Fund (FEDER) through the Operational Program for Competitiveness Factors (POFC) assigned to the Building Physics and Construction Technology Laboratory with the reference SB Tool SPT_2011_4.

In this paper, the distances between pedestrian crossings in twenty one places in the city of Wrocław, together with their evaluation by the researched groups of students, were analyzed. The database created from the collected questionnaires contains a set of two-dimensional variables: the distance between crossings and the rating of the students. The database set was analyzed using a fuzzy data mining approach to create particular clusters. Various numbers of clusters were analyzed, and the division of data into three clusters made it possible to relate the analysis to the LOS methodology. Each variable was enriched with a third dimension representing a membership value. The obtained evaluated distances are similar to values recommended in literature, although the distances highly evaluated by the students do not often occur in reality. This might suggest that there is the need to create new crossings, especially in the city centre, where pedestrian traffic is or should be important.

Communication noise is classified as one of the pollutions for the current environment. Experimental techniques to measure tire-pavement noise generation from asphalt pavements in the laboratory have been limited. A series of experiments were conducted on six different asphalt mixtures to determine if Purdue University’s Tire-Pavement Test Apparatus (TPTA) could be used to overcome these limitations. The procedure produced samples with low tire-pavement noise; however, the air void contents of the samples were higher than designed. Despite these difficulties, the sample preparation technique and the TPTA testing protocol were shown to offer an effective approach for quick laboratory assessment of tire-pavement noise characteristics of hot mix asphalt pavements at a substantially reduced cost compared to field testing.