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This paper reviews the measurement challenges associated with 3D scanning techniques in civil engineering, exploring the practical aspects of scanning buildings and complex surfaces through various case studies. The paper details the conventional use of Terrestrial Laser Scanning (TLS) for reconstructing the technical documentation of a hall. Then it describes an unconventional application of this technique for measuring an External Thermal Insulation Composite System (ETICS) wall, aimed at detecting microdeformations caused by environmental factors controlled within a climatic chamber. Subsequently, the measurements of the insulated wall were repeated using a metrological grade laser scanner. The numerical data were analysed with inspection engineering methods. The deformation maps and displacements of selected reference points were compared. This approach yielded qualitative and quantitative results. The qualitative results, i.e., the distribution of deformations in the form of a map, turned out to be consistent. However, quantitative results show a significant discrepancy in extreme cases of up to 70%.

Lighting of the workplaces has a large impact on safety, proper vision comfort and visual efficiency. The aim of this article is to present an analysis of the lighting of the workplaces of people working on scaffoldings. The researches were carried out on 23 frame-type facade scaffoldings. The scaffoldings were examined from March to October 2017. Due to the specificity of works performed on scaffoldings, the researches were carried out in accordance with an individually adapted research program. The study analyzed the illuminance at particular points and variability in the lighting uniformity in a given workspace. Analysis of the obtained results showed a large variability in illuminance in workplaces of people working on scaffoldings. The measured illuminance levels in the workspaces on the one hand were higher than the minimum illuminance levels defined by the construction site standards, but on the other hand, illuminance levels that may dazzle the employees were also recorded. The luminous intensity depended on the season, time of day, location of the scaffolding, as well as the presence of a protective net installed on the scaffolding, which reduced the occurrence of values that could lead to situations in which the worker could be dazzled. The protective net installed on the scaffolding also reduces the differences in lighting in the scaffolding workspace, improving the lighting conditions of the workplaces.

The paper presents the results of measurements for one hundred and ten scaffolds located in five cities in different parts of Poland. Measurements were made between April of 2016 and October of 2017. The environmental tests performed on scaffoldings were focused mainly on the sound level. The parameters on which we base our analysis are the value of C-weighted peak sound levels and daily noise exposure level. The noise that affects construction workers on scaffolding may influence the behaviour of workers and increase the risk of accidents. And at the same time, noise exposure laws facilitate identification of high noise-emitting activities and provide effective preventive measures that reduce noise pollution and improve work environments. The analyses carried out confirmed the qualitatively expected dependencies, and allowed us to quantify the impact of noise to which scaffolding workers are exposed. In summary, noise measurements on scaffoldings can be a valuable aid in improving working conditions. The analysis of research results allows understanding hazards related to noise in an accessible way. They provide the opportunity to modify the professional environment so that it is more employee-friendly and does not expose them to problems occurring in a noisy work environment.

Scaffolding is equipment usually used at construction sites. A scaffolding structure is lightweight and made of elements used many times. The characteristics of scaffolding make it susceptible to dynamic actions present at the structure or occurring nearby. A scaffolding structure of medium size was subjected to analysis in this paper. The structure FEM model was loaded with single force harmonic excitation with various frequencies ranging from 1 Hz to 12 Hz applied in one of many selected points on the scaffolding façade. In the first step, natural frequencies and mode shapes of the analyzed structure were calculated. Then the full dynamic analysis was carried out to obtain maximum displacements of selected control points. The relation of excitation force frequency and location to the amplitudes of generated displacement was observed. It was found that low excitation frequencies close to the natural frequencies of the structure produced vibrations ranging to large areas of the scaffolding surface. Higher excitation frequencies are usually less propagated at the scaffolding but still may produce some discomfort to the structure users in the vicinity of the excitation force location. Scaffolding is equipment usually used at construction sites. A scaffolding structure is lightweight and made of elements used many times. The characteristics of scaffolding make it susceptible to dynamic actions present at the structure or occurring nearby. A scaffolding structure of medium size was subjected to analysis in this paper. The structure FEM model was loaded with single force harmonic excitation with various frequencies ranging from 1 Hz to 12 Hz applied in one of many selected points on the scaffolding façade. In the first step, natural frequencies and mode shapes of the analyzed structure were calculated. Then the full dynamic analysis was carried out to obtain maximum displacements of selected control points. The relation of excitation force frequency and location to the amplitudes of generated displacement was observed. It was found that low excitation frequencies close to the natural frequencies of the structure produced vibrations ranging to large areas of the scaffolding surface. Higher excitation frequencies are usually less propagated at the scaffolding but still may produce some discomfort to the structure users in the vicinity of the excitation force location.

This article is motivated by ensure the fire safety of the building and deeper understanding on special cements under elevated temperature loads. Knowledge about influence of high temperatures on calcium sulfoaluminate cement (CSA) based materials has crucial impact on ensuring the fire safety of the buildings. CSA based composites are dedicated to special usage in demanding infrastructure constructions. As there is no or insufficient evidence on the influence of heat on calcium sulfoaluminate materials, this article is motivated to extend current literature knowledge on CSA microstructures at higher temperatures up to 800oC. Recognising the effect of high temperature is particularly important given the significant differences between CSA and Ordinary Portland Cement (OPC). Evidence shows influence of mixture proportion on composite structure, filler-matrix bond, and matrix behaviour during temperature exposure. Obtained results might help in understanding phenomena occurring within material under temperature load and determine next research directions in this area.

The article presents the results of research on hazards induced by thermal conditions illustrated by the example of air temperature. Presented results concern ten construction scaffoldings located in Wroclaw, which were investigated from May 30 to October 14, 2016. The scaffolding area ranged from 146 m 2 to 1303 m 2 . On three scaffoldings, the air temperature was above 40 ̊C. The air temperature in 46 % of cases was in the unfavorable for employees temperature range. In addition, people working on scaffoldings are exposed in most cases to strong or severe thermal stimuli connected with large temperature differences during the working day. Unfavorable, dynamically changing climatic conditions pose a serious threat to people working outside. There is an increase in errors, and as a result the risk of situations that could lead to an accident increases.

The article analyses the changes occurring in accidents in the construction industry in Poland. It was analyzed the influence of the season on the number and structure of accidents. Research and analyzes were carried out on the basis of statistical data, made available by the Central Statistical Office, regarding accidents at work in construction that occurred in the period from 2010 to 2018. The total number of accidents at work in the construction sector in in these years shows a significant downward trend. A similar downward trend can also be seen in individual groups of accidents, broken down into light, serious and fatal. Based on the research carried out, the decisive impact of the season on the accident rates in construction sector was noticed. The smallest value of the accident frequency rate in most of the accident types considered can be observed in the winter season. In turn, the highest value of the light and fatal accident frequency rate can be observed in summer season (July - September). Weather conditions, for example, high temperatures and sunshine can lead to dangerous situations which can result in accidents at work. Climate conditions should therefore play an increasingly important role in assessing the risk of accidents.

Windstorms belong to the most costly natural threats in Poland. On August 11-12, 2017, a strong thunderstorm happened which resulted in a catastrophic damage in three provinces: Wielkopolskie, Kujawsko-Pomorskie, and Pomorskie. This disaster has resulted in the death of 6 people, injuries to several dozen people, and enormous property losses including approximately 16,000 residential, utility and public buildings, 80,000 hectares of forest area, 67,000 hectares of agricultural crops, in excess of 300 overhead power line poles, and over 200 cables were downed. The trees felled by the wind blocked and partially damaged local and municipal roads over a length of about 1100 km. Over 500,000 consumers were deprived of electricity at the peak of the disaster. The purpose of this paper is to describe, analyse, and learn from such a dangerous extreme weather event. In order to achieve this, a cause of the thunderstorm, its important meteorological data, the severity of damage to buildings, civil infrastructure and environment, processes of damage surveys, ideas for reconstruction and removing of all damage, financial assistance from the central government, local authorities, and public collections were studied for better preparation of all services and people for mitigation of the effects of a natural disaster which may happen in the future. An example of a building with improved stiffness as the solution for better resistance of wind forces is presented.

The application of recycled concrete aggregates (RCAs) has become increasingly popular for different types of structures, as presented in several studies. However, depending on the type of structure and the region, RCAs might have different properties. This study aims to investigate the application of RCAs of different origins for substructure layers of the cycle paths located in Central Europe, which was not analysed previously. Recycled aggregates from an airport, road overpass, and building demolition were tested according to European standards and used to produce concretes, in which compressive strength, density, water absorption, and frost resistance were tested. After 28 days, RCA concrete had compressive strengths from 5.9 to 17.3 MPa and frost resistance ratios close to 1.0. The concrete parameters indicate that RCAs might be used for the construction of cycle path substructural layers with the appropriate class of cement and W/C ratio. To meet the requirements of EN 12390-3 to achieve class C8/10, RCA concrete with CEM II B/V 32.5 should be used with a W/C ratio of 1. To meet the requirements of D-04.05.01v02, RCA concrete with CEM II B/V 32.5 and a W/C ratio smaller than 1.50 should be used. Applying recycled RCAs in various structures helps protect natural resources by reusing materials. However, the variability in RCA properties requires testing to guarantee quality.

This paper presents the research data of the fire-temperature influence on Portland CEM I (OPC) and calcium sulfoaluminate (CSA) types of cement blend composites as cooling materials dedicated for infill and covers in fire systems. The data present the material responses for four types at high-temperature elevation times (0, 15, 30, 60 min), such as core heat curves, differences in specimens color, flexural and compressive strength parameters. Materials were tested using the DSC method to collect information about enthalpies. The differences between cement blend composites were compared with commonly used cooling materials such as gypsum blends. It is shown that modifications to Portland cement composites by calcium sulfoaluminate cement have a significant influence on the cooling performance during high-temperature, even for 60 min of exposure. The temperature increase rates in the material core were slower in composites with regards to additionally containing calcium sulfoaluminate in 100–150 °C range. After 60 min of high-temperature elevation, the highest flexural and compressive strength was 75% OPC/25% CSA cement composition. The influence on cooling properties was not related to strength properties. The presented solution may have a significant influence as a passive extinguisher solution of future fire resistance systems in civil engineering.