Building Material Samples Research Articles

Possibility of using sawdust in sawdust concrete

According to GOST 19222-84, the dependence of the physical-mechanical characteristics of sawdust concrete on the specific gravity of wet sawdust of coniferous species and ash-slag mixture in the composition was studied. A one-factor experiment was carried out in the laboratory of the Department of Reproduction and Processing of Forest Resources, Federal State Budgetary Educational Institution of Higher Education “Bratsk State University” in order to justify the specific share of wet sawdust in the composition of sawdust concrete, to determine the necessary number of observations and repetitions of the experiment. As a variable factor, the proportion of wet sawdust of coniferous species in the composition is assumed. The proportion varies from 17% to 37% in increments of 5%. The applicability of wet sawdust of coniferous species for the production of heat-insulating building materials is established. Samples of building materials were made; the necessary laboratory tests were carried out. The range of variation of sawdust content in the composition for sawdust concrete is determined (from 17 to 32%).

Radioactivity of building materials in Mahallat, Iran – an area exposed to a high level of natural background radiation – attenuation of external radiation doses

In this study, mass activity of naturally occurring radioactive materials were measured in twenty-three building material samples, use extensively in the area exposed to a high level of natural background radiation (Mahallat, Iran), to determine the radioactivity index and changes to the level of indoor gamma radiation. The mass activity of 232Th, 226Ra and 40K were within the ranges from 18 ± 3 to 44 ± 10 Bq/kg (average of 27 ± 6 Bq/kg), 22 ± 5 to 53 ± 14 Bq/kg (average of 34 ± 6 Bq/kg) and 82 ± 18 to 428 ± 79 Bq/kg (average of 276 ± 58 Bq/kg), respectively. The gamma dose rates for population were estimated between 48 ± 9 and 111 ± 26 nGy/h with exception of radon exhalation from building materials. Since the air kerma rate in the town varies from 0.8 to 4 μGy/h, the attenuation coefficient was calculated for buildings made of the aforementioned materials. Additionally, the annual gamma radiation doses for inhabitants were calculated based on time spent outdoors and indoors.

Building material radon emanation and exhalation rate: Need of a shared measurement protocol from the european database analysis

In this paper the authors present a collection of radon emanation and exhalation rate data of about 2000 samples of building materials used in Europe. The data analysis highlighted some critical issues, such as the use of different units to express radon exhalation rate, the use of different measurement techniques and the general lack of information about density and thickness of samples. In many cases these differences of type and amount of information make difficult a reliable comparison of the obtained data. In the light of these considerations, the need arises to start, at both national and European level, a research activity aimed to develop a shared protocol for measuring the radon exhalation rate based on widely used and reliable measurement techniques. At European level, this protocol could support in forthcoming EU Member States national radon action plans, to take into account the contribution of building materials to the indoor radon concentrations.

Analysis of the effects of adding pyroclastic rock to red mud for the production of a baked building material in terms of its resistance to frost actions

In the aluminum sector, approximately 130 million tons of waste red mud was produced in the last year. Such a high amount of wastes causes their storage areas to become a threat to the environment. Numerous studies have been conducted in the literature to eliminate this environmental threat. However, it is observed that these studies are mostly conducted on only a part of the waste, and there are few studies on the whole consumption of waste. Due to the said lack in the literature, it is thought that this waste can be utilized as a baked building material and consumed systematically. However, according to the literature and previous studies, it is observed that the use of the waste alone will not produce a quality building material. Therefore, otiose pyroclastic rocks were included within the scope of the study to be used together with the waste material. Accordingly, micronized pyroclastic rocks obtained from different regions were added to red mud at the proportions of 10, 20, 30, 40, and 50% by weight. Bentonite of 3% was added to mixtures to prevent capillary cracks. As a result of the preliminary experiments conducted on the baked building material samples obtained with the above-mentioned mixture ratios, two mixture types from each region with the highest compressive strength were selected. Physical and mechanical experiments were conducted on the samples to determine the resistance to frost actions—as an outer ambient condition with the most destructive effect—of the baked building materials (especially brick, etc. with the widest area of usage in outer walls and surface cover materials such as ceramic, clinker pavement, etc.) which will be obtained with these mixtures. As a result of the study, the optimum mixture type was determined to be the sample formed by adding 10% volcanic tuff around campus to red mud and baking it at a temperature of 1050 °C. Furthermore, different mixture types formed by adding the micronized pyroclastic material from other regions could reach sufficient values in terms of both compressive strength and frost actions. According to the results of the study, this material will fulfill the need for raw material as a building material resistant to frost actions and used in outer masonry. In this study, a process was obtained to eliminate a potential environmental problem, and a contemporary building material intended to be used as a sustainable building material was produced.

Desert Environment Effect on the Deterioration of Ancient Building Materials in Archaeological Buildings (El- Bagawat Tombs, El - Kharga Oasis as an Example)

Environmental changes have severe effect on the deterioration of archaeological buildings, desert environment distinguishes with the climatic changes daily and seasonally , which affect badly on the ancient building materials, air temperature variation, relative humidity and wind are the main factors that cause the materials degradation. This research aims to shed the light on desert environment's effect on ancient building materials at El - Bagawat tombs in El- Kharga oasis – Egypt, these tombs, return to early Coptic era, building materials samples were taken mainly mud bricks and mortars , examined and analyzed by scanning electron microscope (SEM) , EDAX unit attached to SEM and polarizing microscope to study the desert's effect , environmental measures were mentioned also like air temperature degrees , relative humidity percentages and wind's direction and speed. El-Kharga oasis is characterized by climate changes throughout the year, these changes reflect on the degradation of building materials in El-Bagawat tombs like mud bricks and mortars.

КОНТРОЛЬ РАДІОАКТИВНОСТІ ЖИТЛА В УКРАЇНІ

The main sources of natural radiation in Ukraine and their location are given. High levels of natural radioactivity were noted. The elements with the greatest influence on the formation of radioactive background in our country are indicated. The content of natural radionuclides in building materials of Ukraine is considered. Listed are organizations that provide services in the manufacture of radiation measurement devices in Ukraine, as well as organizations that provide services for measuring radioactivity. The cases of contamination of houses due to the use of radioactive bricks, as well as several consignments of gas block due to insufficient quality control of products, as well as the desire of the customer to save on "cheap" bricks are indicated. The basics of the methodology for determining the radioactivity of building materials in Ukraine, the preparation of a test sample and the spectrometric measurement of radioactivity of natural radionuclides in samples of building materials are presented. The specified norms of radioactivity of building materials, specific effective activity and class of building materials. Ways to reduce the radioactivity of building materials are suggested.

Radioactivity of building materials in Serbia and assessment of radiological hazard of gamma radiation and radon exhalation

This paper presents a gamma spectrometric analysis of 47 samples of building materials produced and used in Serbia. Based on the measured activity concentrations of 226Ra, 232Th, and 40K, radiological hazard indices and annual effective doses were estimated for human exposure in the rooms. The values of radon surface exhalation rate and indoor radon concentration, as well as the range of indoor radon exposures for typical building materials produced in Serbia (concrete, mortar, clay bricks, granite, siporex, ceramic and concrete tiles), were estimated. Measurements of the dose rate for building materials in one typical home in Serbia were performed in contact geometry using the radiation monitor Radiagem 2000.

Complex dispersed analysis of particles applying in output hydrodynamic criteria decreasing dust leakage’ throw collectors of aspiration in construction industry

The article is devoted to the issue of improving the environmental safety of the construction industry by improving dust collectors of dust removal systems using additive-complex dispersive analysis of variance of dust emissions by aspiration systems. The article proposes the improvement of complex analysis of variance using hydrodynamic criteria in output functions. Modified output data and additive-simplex approach to the evaluation of characteristics - equivalent sizes and speeds of sedimentation-soiling of dust particles make it possible to determine the ranges of their changes with a higher degree of accuracy of the results. The distributions of the hydrodynamics criteria values allow us to obtain reliable meanings for sedimentation velocities and equivalent particle’s sizes for the studied dust samples of building materials. Analytical approach to determining the density distribution of the numerical values of the criteria allowed clarifying the values of sedimentation-soiling velocities and hydraulic equivalent sizes of particles to get more reliable of their changes ranges. The authors present the most essential regressions and mark to method determining hydraulic work regimes for design dust collectors. This approach is one of the most effective ways to improve the environmental safety of the construction industry.

Studying firebrands interaction with flat surface of various wood construction materials in laboratory conditions

The behavior of wood building materials (plywood, oriented strand board, particle board) exposed to burning and smoldering firebrands is investigated in this work. To control the temperature on the surface of the samples, an infrared camera (JADE J530SB) with a 2.5–2.7 micron optical filter that can record the temperature in the range of 300–800 °C was used. The Canon HF R88 video camera was used to evaluate the ignition delay and the behavior of firebrands after falling onto the surface of wood building material samples. In the wind speed range of 0–1 m/s, the ignition of the samples was not observed. A small amount of additional oxidant influx in the landing zone of firebrands caused their slow smoldering on the surface until complete combustion. Thus, it can be concluded that smoldering natural firebrands does not affect the ignition of wood building material samples for the selected experimental parameters. The probability of ignition and the ignition delay of wood were determined depending on the size and number of firebrands, the presence of the air flow in the landing zone of particles, as well as on the initial temperature of wood. The experimental temperature distribution was obtained on the surface of wood exposed to the model ground fire using infrared thermography.

Toxicity Risks of Selected Heavy Metal on Dwellers from Building Materials Used in Nigeria

Chemical toxicity risks from 14 different brands of building materials such as Cements, tiles, marbles and sands were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). This study is aimed at determining the risk exposure to dweller of different age groups. The digested samples analysed using ICP-MS for the concentrations of Cr, Pb, Zn, Ni, Fe, As and Cd varies from 10 to 183, 8.96 to 68.70, 35.4 to 733.7, 14.4 to 690.5, 0.95 to 4.64 and 0.7 to 14.7 mgkg−1respectively. Statistical Analysis showed that 44% of the Concentrations of Toxic metals measured in the building material samples come from Ni, the scree plots of dermal and inhalation risks exposure to children aged from 0.5 to 11 years showed sharp drop after Ni metal compared to adult with ages ranges from 12 to 70 years where the drop is steady from the first factor. This indicated that Adults are not over-exposed compared to children to these heavy metals. The High factor value of 2.786 was seen in Goodwill Verified. Tile High factor scores were discovered from the exposure of children to both dermal and inhalation risks compared to the Adults. Some of these concentrations and risks exceed the permissible limits of the European Regulatory Standards and USEPA. Significantly, these chemical toxicity risks of heavy metal contents in the building materials may pose health risks on dwellers especially the under-aged children.

Comparative analysis of gamma dose rates measured by ion chamber in and around the historical sacral objects in Bosnia and Herzegovina

The main objective of this study was to investigate the correlation between the indoor and outdoor ambient dose equivalent rates measured by the ion chamber inside and around the historical sacral objects at a few locations in Bosnia and Herzegovina. The investigated objects made of the traditional building materials were built in the Late Medieval, Post Medieval, and Ottoman Period of Bosnia and Herzegovina history. The LUDLUM Model 9DP instrument based on a pressurized ion chamber was selected for natural low level radiation measurements since the ionisation chambers have higher sensitivities than the other types of detectors. The detection capability of the LUDLUM Model 9DP pressurized ion chamber was examined in the laboratory conditions with a source of low activity and under natural environmental radiation conditions by measuring the indoor and outdoor dose rates. A weak positive correlation was found between the ambient dose equivalent rates inside the historical sacral objects and the dose rates outside the objects. The average evaluated value of the indoor to outdoor dose rate ratio of 1.07 for the studied historic objects is less than that obtained for the contemporary building materials such as concrete. No study on the indoor to outdoor dose rate ratio in Bosnia and Herzegovina measured by the LUDLUM 9DP dose rate meter based on an ion chamber has been conducted yet. In addition to direct measurements, the first gamma spectrometric analysis of a few samples of building materials from the Late Medieval period in Bosna and Herzegovina was performed. The results of the gamma analysis revealed almost uniform distribution of primordial radionuclides in the investigated samples. It was demonstrated that such materials had the reduced content of radioactive isotopes compared to the contemporary building materials and therefore they could have potential advantages in specific applications related to the environmentally sustainable architecture.

Measurement of radon exhalation rate in various building materials used in Morocco

Measurements of radon surface and mass exhalation rates were made for 35 types of building material samples frequently used in Morocco. In this survey, we used the Can technique, containing CR-39 detectors, to estimate the radon exposure from building materials. The surface and mass exhalation rates ranged from 37.92 mBq−2 h−1, 3.05 mBq kg−1 h−1 to 1545.60 mB q m−2 h−1, 43.14 mBq kg−1 h−1, with an average of 271.4192 mBq m−2 h−1 and 10.23 mBq kg−1 h−1, respectively. All the values of effective radium content and effective dose were calculated and they were within the safe limit in all samples studied.

Determination of indoor doses and excess lifetime cancer risks caused by building materials containing natural radionuclides in Malaysia

Abstract The activity concentrations of 226Ra, 232Th, and 40K from 102 building materials samples were determined using a high-purity germanium (HPGe) detector. The activity concentrations were evaluated for possible radiological hazards to the human health. The excess lifetime cancer risks (ELCR) were also estimated, and the average values were recorded as 0.42 ± 0.24 × 10−3, 3.22 ± 1.83 × 10−3, and 3.65 ± 1.85 × 10−3 for outdoor, indoor, and total ELCR respectively. The activity concentrations were further subjected to RESRAD-BUILD computer code to evaluate the long-term radiation exposure to a dweller. The indoor doses were assessed from zero up to 70 years. The simulation results were 92 ± 59, 689 ± 566, and 782 ± 569 μSv y−1 for indoor external, internal, and total effective dose equivalent (TEDE) respectively. The results reported were all below the recommended maximum values. Therefore, the radiological hazards attributed to building materials under study are negligible.

Exhalation rate of radon-222 from concrete and cement mortar

Abstract The main sources of radon in the air of dwellings are soil, building materials, and groundwater. This study aimed to determine the exhalation rate of 222Rn from samples made of concrete and cement mortars, as well as to evaluate by means of gamma spectrometry the hazard indexes associated with other radionuclides present in the studied samples of building materials. The results obtained allowed the comparison of the exhalation rate of radon using theoretical calculations based on one-dimensional and three-dimensional models. Measurements of the activity concentration of radon in air was performed by AlphaGuard radon detector. Furthermore, obtained results were compared with the measurements performed inside the concrete test cells. These test cells were built with the aim of simulating a dwelling in small dimensions and to evaluate indoor radon activity associated with concrete. Consequently, the obtained results of radon exhalation rate, in becquerel per meter squared per hour, for the concrete was 2.55 ± 0.03 Bq·h−1·m−2 for the 1D model and 0.461 ±0.008 Bq·h−1·m−2 for the 3D model. The exhalation rate of radon, for the cement mortar was 1.58 ± 0.03 Bq·h−1·m−2 for the 1D model and 0.439 ± 0.011 Bq·h−1·m−2 for the 3D model. The indoor concentration of 222Rn from the test cell was 112 ± 9 Bq/m3. These values were below the limit of 300 Bq/m3 recommended by the International Commission on Radiological Protection (ICRP) and <148 Bq/m3, the limit recommended by the US Environmental Protection Agency (US EPA). Even so, these values should be the subject of concern since that activity is related only to the contribution of concrete walls.

Neutron Activation Analysis of Some Building Material

Neutron activation analysis (NAA), based on the comparator method, has the potential to fulfill the requirements of a primary ratio method as defined in 1998 by the Comité Consultatif pour la Quantité de Matière — Métrologie en Chimie (CCQM, Consultative Committee on Amount of Substance — Metrology in Chemistry Studies of Neutron Activation Analysis (NAA) have been carried out on different Egyptian building material samples. The technique of neutron activation analysis is based on the measurement of radiation released by the decay of radioactive nuclei formed by neutron irradiation of the material. The most suitable source of neutrons for such an application is usually a research reactor. The samples that can be analyzed with this method stem from a number of different fields, including medicine, nutrition, biology, chemistry, forensics, the environment and mining. Neutron activation analysis can be performed in a variety of ways. This depends on the element and the corresponding radiation levels to be measured, as well as on the nature and the extent of interference from other elements present in the sample. Most of the methods used are non-destructive, based on the detection of gamma radiation emitted by the irradiated material after or during the irradiation. Next to education and training, neutron activation analysis is the most widely used application of research reactors. Almost any reactor operating at 10-30 kilowatt of thermal power is capable of providing a sufficient neutron flux to irradiate samples for selective applications of this analysis technique. Another method of NAA by using two Am-Be isotopic neutron sources of activity 5 Ci were used in this investigation. The accomplished gamma rays were measured using 70 % HPGe spectrometer. This work demand to estimate the elements contained in cement products and its quality control. X-ray Fluorescence (XRF) measurements were done for confirming our results, and for determining the average neutron flux of 3.7× 103 n/cm2sec. The Natural radioactivities of these samples were measured before the analysis to know the background level of 40K, 238U and232Th nuclei. The results investigated that NAA agree with the results of XRF and the world range of the cement concentration of the essential elements Ca, Al, Na, Fe, Mn, V, Sr and Si.

Prediction of indoor radon/thoron concentration in a model room from exhalation rates of building materials for different ventilation rates

Studies have confirmed that elevated levels of radon/thoron in the human–environments can substantially increase the risk of lung cancer in general population. The building materials are the second largest contributors to indoor radon/thoron after soil and bedrock beneath dwellings. In present investigation, the exhalation rates of radon/thoron from different building materials samples have been analysed using active technique. Radon/thoron concentrations in a model room have been predicted based on the exhalation rates from walls, floor and roof. The indoor concentrations show significant variations depending upon the ventilation rate and type of building materials used.

RADON EXHALATION FROM BUILDING MATERIALS USED IN YEMEN.

The present article seeks to determine the annual effective doses of 222Rn exposure, effective radium content and radon exhalation rates in some building materials from the local market of Ibb province, Yemen. A total of 33 samples of building materials were collected from the target area. The radon exhalation rate and effective radium content in these samples were measured using solid-state nuclear track detector, which has become an important tool in every investigation of the radon levels in the surrounding environment. Surface exhalation rate has been found to vary from 178.90 to 1267.6 mBq m-2 h-1, whereas mass exhalation rate has been found to vary from 5.51 to 33.25 mBq kg-1 h-1. All the values of effective radium content in all samples under test were found to be quite lower than the permissible value of 370 Bq kg-1 recommended by Organization for Economic Cooperation and Development. Annual effective doses have also been estimated.

Brief Analysis on Sampling and Testing Method of Concrete Specimen of Building Materials

In recent years, the construction industry in China has developed very rapidly. The demand for concrete for building materials has also increased. Concrete as a basic construction material for construction projects, its application performance also has a very big impact on the overall construction quality of the construction project, which also requires that all construction companies can do a good job in the detection of concrete specimens, only in this way that we can fully guarantee the application performance of concrete, to lay a good foundation for the smooth construction of the construction project. This article mainly studies the sampling and detection methods of concrete samples of building materials.

Assessment of Exposure Due to Technologically Enhanced Natural Radioactivity in Various Samples of Moroccan Building Materials

The aim of our present work is to measure the specific activities of the radionuclides 226Ra, 232Th, 40K and the exhalation rates in terms of area and mass of 222Rn in some samples of building materials commonly used in Morocco in order to evaluate the radiological risk caused by natural radioactivity. To this end, the analyses were carried out, using two nuclear techniques, namely high resolution gamma spectrometry and alpha dosimetry based on the use of LR115, on 50 samples collected from large commercial suppliers in Morocco. The results of these analyses show that the average specific activities of 226Ra, 232Th and 40K in these materials vary from 9 to 52 Bq/kg, 3 to 63 Bq/kg and 68 to 705 Bq/kg respectively. These activities remain within the permissible limits of 35 Bq/kg, 30 Bq/kg and 370 Bq/kg respectively, with the exception of a few samples of red brick, gray cement, ceramic and granite. The activity of the radium equivalent (Raeq), the internal (Hin) and external (Hex) hazard indices, the absorbed dose rate, the total annual effective dose , the excess lifetime cancer risk (ELCR) as well as volumic activities, exhalation rates in terms of area (ES) and mass (EM) are calculated for the samples analyzed in this work in order to assess the radiological risks resulting from the use of these materials in various construction activities. It seems that the values of these indices vary from 19 to 196 Bq/kg, 0.08 to 0.67, 0.05 to 0.53, 9 to 91 nGy/h, 0.05 to 0.56 mSv/y, 0.19 × 10−3 to 1.96 × 10−3, 72 to 350 Bq/m3, 56 to 273 mBq⋅m−2⋅h−1 and 3 to 15 mBq⋅kg−1⋅h−1 respectively. The lowest values are identified for gypsum, while the highest are attributed to granite. All of the obtained results of these indices respect the permissible limits except for the Raeq in some granite samples, the ELCR index in all samples except gypsum and the radon volumic activity in some gray cement samples, ceramic and granite. As a result, the different types of building materials analyzed in our work do not present a health risk to the public and can be used in various construction activities, with the exception of a few samples of red brick, gray cement, ceramic and granite. The choice of the use of red brick, gray cement and ceramic should be monitored and adapted according to the criteria of the limitation of the doses whereas the use of the granite must be moderate in order to limit over time the health risk which increases with the duration of exposure of humans to these building materials.

Alternately airtight/ventilated emission method: A universal experimental method for determining the VOC emission characteristic parameters of building materials

The volatile organic compound (VOC) emissions of building materials are characterized by three key parameters: the initial emittable concentration (C0), the partition coefficient (K), and the diffusion coefficient (D). Accurate determination of these three parameters is the basis for understanding VOC emission characteristic and the prerequisite for determining appropriate control strategies. In this paper, an alternately airtight/ventilated emission (AAVE) method for efficient and accurate determination of VOC emission characteristic parameters of building materials is proposed. By switching the airtight/ventilated emission mode of the building material samples, the equilibrium concentration in the airtight state and the dynamic concentration in the ventilation state were measured. K and C0 can be simply calculated by linear fitting of experimental data. Compared to the multi-emission/flush regression method and the variable volume loading method, the AAVE method requires less pre-adjustment process and has a wide measurement range. Compared to the two remarkably efficient measurement methods, the closed/ventilated chamber C-history methods, the AAVE method requires fewer intermediate parameters, simpler calculation process, and has a better error tolerance to the process data. The formaldehyde emission characteristic parameters of four types of building materials were measured using the AAVE method and verified by independent experiment. The experimental results indicated the reliability of the AAVE method. Finally, an optimized selection method of the ventilation parameters is proposed for adapting to the characteristic parameter measurement of various building material-VOC pairs.