Raw Building Materials Research Articles

Natural Radioactivity in Raw Building Materials for Underground Parking Lots and Assessment of Radiological Health Risk for the Population.

This article reports the results of an investigation into the activity concentration of natural radionuclides in raw building materials for underground parking lots, together with the assessment of the radiation hazard for the public related to exposure to ionizing radiations. To this purpose, high-purity germanium (HPGe) γ-ray spectrometry was employed in order to quantify the average specific activity of 226Ra, 232Th, and 40K natural radioisotopes. With the aim to assess any possible radiological health risk for the population, the absorbed γ-dose rate (D), the annual effective dose equivalent outdoor (AEDEout) and indoor (AEDEin), the activity concentration index (I), and the alpha index (Iα) were also estimated, resulting in values that were lower than the maximum recommended ones for humans. Finally, the extent of the correlations existing between the observed radioactivity and radiological parameters and of these parameters with the analyzed samples was quantified through statistical analyses, including Pearson's correlation, a principal component analysis (PCA), and a hierarchical cluster analysis (HCA). As a result, three clusters of the investigated samples were recognized based on their chemical composition and mineralogical nature. Noteworthily, this paper covers a certain gap in science since its topic does not appear in literature in this form. Thus, the authors underline the importance of this work to global knowledge in the environmental research and public health fields.

Study of radium content and radon exhalation rates in raw building materials used in southern India

As a potential source of indoor radiation arising from radon, a range of building materials (white cement, gray cement, gravel, gypsum, granite, marble, vitrified tile, and brick) were studied for the specific activity of radium and radon gas exhalation rates. The activity of radium was determined using scintillation gamma-ray spectrometry. Exhalation rates were assessed using passive and active measurement methods. Radon mass exhalation rates from powdered building materials and radon surface exhalation rates from slab-type building materials were measured. Activity concentrations of 226Ra in powder and slab-type building materials were found in the range of (1.12 – 14.98) Bqkg−1 and (17 – 308) Bqkg−1, respectively. 222Rn mass exhalation rates (mBqkg−1h−1) from the building materials were in the range of 15.0 ± 0.8 (gray cement) to 1.1 ± 0.1 (gravel). Surface exhalation rates (mBqm−2h−1) for slab-type materials have a range of 317 ± 9 (brick) to 8 ± 2 (marble). Strong positive correlations were found between the specific activity of radium and radon mass exhalation rates (r = 0.9408) and radon surface exhalation rates (r = 0.7167) for building materials investigated. Obtained data indicates that the building materials used influence indoor radon concentration in dwellings.

FIELD STUDIES OF TEMPERATURE DISTRIBUTION IN A STRAW BUILDING WALL

It is proven that human construction activities affect the environment negatively. The threat of global ecological disaster is one of the most important factors, appearing due to unbalanced human activities and insufficient use of natural resources. In Lithuania there are building materials (bricks, concrete, reinforced concrete and other materials) used for construction of buildings that require a lot of energy. Prices of energy grew up several times in recent years, so the prices of construction materials significantly increased. It is suggested to use more local building materials produced with low energy consumption. The usage of local, renewable raw building materials can reduce CO2 emissions, ambient air pollution. The use of straw bales as construction material has many advantages. Pressed straw can be used as a natural heat insulating material in the construction of buildings in Lithuania, as it does not contradict the essential requirements of the construction of buildings specified in the Law on Construction and other normative documents. The aim of this study is to evaluate the temperature distribution of the wall of a built building made of straw bales during the cold period of the year. Temperature data loggers with thermocouple sensors were used to record the outdoor air, indoor and wall temperatures. Measurements of the temperature of the wall frame of the building filled with straw showed that the temperature field of the wall is in a constant dynamic state. It was found that the temperature of the individual layers of the walls of the building filled with straw varies tendentiously depending on the outdoor air temperature.

Overall Utilization of Ti-Extraction Blast Furnace Slag as a Raw Building Material: Removal of Chlorine from Slag by Water Washing and Sintering

Overall Utilization of Ti-Extraction Blast Furnace Slag as a Raw Building Material: Removal of Chlorine from Slag by Water Washing and Sintering

Rice Husk Ash-Based Concrete Composites: A Critical Review of Their Properties and Applications

In the last few decades, the demand for cement production increased and caused a massive ecological issue by emitting 8% of the global CO2, as the making of 1 ton of ordinary Portland cement (OPC) emits almost a single ton of CO2. Significant air pollution and damage to human health are associated with the construction and cement industries. Consequently, environmentalists and governments have ordered to strongly control emission rates by using other ecofriendly supplemental cementing materials. Rice husk is a cultivated by-product material, obtained from the rice plant in enormous quantities. With no beneficial use, it is an organic waste material that causes dumping issues. Rice husk has a high silica content that makes it appropriate for use in OPC; burning it generates a high pozzolanic reactive rice husk ash (RHA) for renewable cement-based recyclable material. Using cost-effective and commonly obtainable RHA as mineral fillers in concrete brings plentiful advantages to the technical characteristics of concrete and to ensure a clean environment. With RHA, concrete composites that are robust, highly resistant to aggressive environments, sustainable and economically feasible can be produced. However, the production of sustainable and greener concrete composites also has become a key concern in the construction industries internationally. This article reviews the source, clean production, pozzolanic activity and chemical composition of RHA. This literature review also provides critical reviews on the properties, hardening conditions and behaviors of RHA-based concrete composites, in addition to summarizing the research recent findings, to ultimately produce complete insights into the possible applications of RHA as raw building materials for producing greener concrete composites—all towards industrializing ecofriendly buildings.

Slag uses in making an ecofriendly and sustainable concrete: A review

A single ton of ordinary Portland cement (OPC) demands around 4.0 G Joule energy and creates about a ton of CO2 emission. As part of our effort to preserve the environment, the incorporation of ground granulated blast-furnace slag (GGBFS) or fully replaced by alkali-activated slag (AAS) as an alternative binder to OPC. This concrete is environmental-friendly and also eases concerns in energy usage, raw material, and manufacturing cost for the traditional concrete. The cementitious properties of GGBFS and AAS promote their usage in the concrete matrix. Partial inclusion of slag for cement produces OPC or fully replaced by AAS is getting more attention as it is more pumpable, chemically stable, and resistant to an aggressive environment. This paper reviews the source, clean production and chemical compositions of the GGBFS and AAS. This literature review also objects to provide reviews on the properties, hardening conditions, and behaviors of GGBFS and AAS -based concrete composites as well as to synopsize the research development trends to generate comprehensive insights into the potential applications of GGBFS and AAS concrete as raw building materials for making sustainable and greener concrete composites, towards industrializing ecofriendly buildings today.

Semi-experimental evaluation for radon exhalation rate and excess lifetime cancer risk from potential radon exposure for using fly ash building materials

In this work, the radon exhalation, annual effective dose and excess lifetime cancer risks due to the exposure of radon released from raw building materials containing fly ash of different fractions were evaluated. The 226Ra and 222Rn concentrations were evaluated by the measurements on HPGe gamma spectrometer, RAD 7 radon detector combined with model calculation of radon exhalation for standard rooms. The results indicated that the emanation fraction for fly ash is lower than the corresponding value for soils and rocks. The surveyed building materials of containing fly ash can result in an indoor radon concentration up to 1.7 Bq m−3 which is below the recommended value of 100 Bq m−3 by WHO, the annual effective dose increases from 0.007 to 0.022 mSv year−1, the excess lifetime cancer risks ranges from 0.027 × 10–3 to 0.085 × 10–3 with the ratio of 3.2 for the additional fly ash content in cement up to 75%. In the meanwhile, it has a down trend and influences inconsiderably on these parameters for sand. The obtained mean annual effective doses are lower than the dose limitation of 10 mSv year−1 recommended for occupational workers.

Excessive radon-based radiation in indoor air caused by soil building materials in traditional homes on Đồng Văn karst plateau, northern Vietnam

Radon-based radiation from natural soil building materials is an important factor likely influencing residents’ health as a contributing source of natural radiation. This survey aims to quantify the nuclide-specific α-radiation of isotopes 222Rn and 220Rn in common types of houses in a region of northern Vietnam, Đồng Văn karst plateau, to preliminarily (i) evaluate the total annual effective dose rates and (ii) assess the relative risk of cancer induction from indoor α-radiation for inhabitants. The average 222Rn concentrations in all house types were lower than 100 Bq m−3, but 220Rn abundances were far higher than 222Rn, even up to >1000 Bq m−3 in air close to a wall of unfired-soil bricks. The estimated total annual effective dose rates from indoor 222Rn and 220Rn and their progenies to residents with daily exposure of 13 h in the various types of houses range from 3.1 to 4.3 mSv a−1 for houses constructed with modified materials, but up to higher than 6 mSv a−1 in houses with raw building materials. The average risk of developing lung cancer as a consequence of a lifetime exposure to indoor α-radiation in affected homes ranges from 3.9% to 14.6%. 220Rn and its metallic progenies contribute more than 80% of the total average lung cancer risk from total radon, being responsible for a range of 2.7–14.6% of the risk of developing lung cancer.

The Raw Building Materials’ Research Quantitative Characteristics Radioactivity in Volgograd Region

The paper attempts to structure the raw materials for radioactivity using Kohonen self-organizing maps. The analysis was carried out on the data on the specific activities of natural radionuclides in the construction raw materials in the Volgograd region, as well as on the natural radionuclides specific effective activities calculated values. Unlike the traditional methods of analysis, the used methodology for assessing radioactivity is based on quantitative characteristics. As a result of the network training on data on the raw materials specific activities, a cluster map with segmentation by the natural radionuclides effective specific activity has been obtained. Based on the results obtained, the conclusions about the possibility and feasibility of using the algorithm used for the classification and analysis of data on the building materials radioactivity have been made.

The Second Life of Inscriptions in Late Antique and Byzantine Asia Minor: Some Remarks on the Reuse of the Inscribed Material

Classical, Roman and Late antiquity inherited in the land of Asia Minor thousands of older Greek and Latin inscriptions on stone, of various content and purposes. With the collapse of the ancient world and the transition to the medieval period, this material lost its significance as conveyor of public and private texts and became incomprehensible to the viewers. In the meantime, contem­porary epigraphy followed a different orientation and acquired new values, in the service of Chris­tianity and the Eastern Roman imperial institutions. Fortifications, public infrastructure and churches predominate in the building activity in the re­gion during this long period. Taking place primarily at ancient cities and sites full of earlier ma­terial, architectural production extensively reused spolia of various kinds and periods. These spo­lia included many inscriptions, which were embedded –intact or reworked– in various structures. The walls of Ankara, the churches of Ephesus and other monuments are representative of this practice, which was later exercised by the Seljuks and the Ottoman Turks too. The presence of inscribed spolia in Byzantine monuments of Asia Minor raises several questions about the attitude towards the written word in a society which was still using the same language, in a somehow changed form, but was sharing a different culture. Based on selected cases of reused epigraphic material from the Asia Minor, this article argues that inscriptions were treated mainly in practical terms. Being more or less incomprehensible by illiterate and literate Byzantines, in­scribed stones became raw building materials available to be recycled in fortifications, secular buildings and churches.

PEMANFAATAN NIPAH (Nypa frutican Wurmb) DI DUSUN SUKA MAJU DESA SUNGAI SEPETI KECAMATAN SEPONTI KABUPATEN KAYONG UTARA

Nipah is one of the non-timber forest products whose all the part of the plant can be utilized. This research aimed to find out the information on various forms of utilization of nipah by the community of Suka Maju hamlet in Sungai Sepeti village Kayong Utara regency. This study used a descriptive method with direct interview technique to a number of respondents to get response. Sampling was perfomed with snowball sampling method. The results showed that the community of Suka Maju Hamlet of Sungai Sepeti village in Seponti Subdistrict of Kayong Utara Regency utilized 5 parts of the nipah namely leaves, shoots, sticks, fruit, and flowers. Using The parts of the nipah, people can use its leaves as roof or as raw building material, nipah shoots for making of art craft woven mats, rice countainer, and cigarette, sticks on the sticks for making brooms, the fruit for making kolang kaling, an the flower can be consumed and used as a temporary treatment for fever.Keywords: Nipah, Snowball Sampling, Suka Maju Hamlet, Utilization

Chemical and multi-physical characterization of agro-resources’ by-product as a possible raw building material

The aim of this paper is to find out the best valuation of agro-resources’ by-products as new alternative raw building materials that meet to sustainable development requirement. Five agro-resources are considered: flax, hemp, corn, rape and wheat. In the present work, the chemical characteristics of bio-aggregates are studied by FTIR, Van soest method and Phenol sulfuric method to identify their composition. The investigated physical properties are particle size distribution, density, porosity, water absorption, thermal conductivity and moisture buffer value. The studied materials differ on a chemical and a thermal point of view while they all are excellent hygric regulators. These results suggest that agro-resources can be used as a raw building materials for several types of use: as lightweight aggregates or as binder.

Supplementation of specific carbohydrates results in enhanced deposition of chondrogenic-specific matrix during mesenchymal stem cell differentiation.

Repair or regeneration of hyaline cartilage in knees, shoulders, intervertebral discs, and other assorted joints is a major therapeutic target. To date, therapeutic strategies utilizing chondrocytes or mesenchymal stem cells are limited by expandability or the generation of mechanically inferior cartilage. Our objective is to generate robust cartilage-specific matrix from human mesenchymal stem cells suitable for further therapeutic development. Human mesenchymal stem cells, in an alginate 3D format, were supplied with individual sugars and chains which comprise the glycan component of proteoglycans in articular cartilage (galactose, hyaluronic acid, glucuronic acid, and xylose) during chondrogenesis. After an initial evaluation for proteoglycan deposition utilizing Alcian blue, the tissue was further evaluated for viability, structural elements, and hypertrophic status. With the further addition of serum, a substantial increase was observed in viability, the amount of proteoglycan deposition, glycosaminoglycan production, and an enhancement of Hyaluronic Acid, Collagen II and Aggrecan deposition. Suppression of hypertrophic markers (COL1A1, COL10A1, MMP13, and RUNX2) was also observed. When mesenchymal stem cells were supplied with the raw building materials of proteoglycans and a limited amount of serum during chondrogenesis, it resulted in the generation of viable hyaline-like cartilage with deposition of structural components which exceeded previously reported in vitro-based cartilage.

Local geology controlled the feasibility of vitrifying Iron Age buildings

During European prehistory, hilltop enclosures made from polydisperse particle-and-block stone walling were exposed to temperatures sufficient to partially melt the constituent stonework, leading to the preservation of glassy walls called ‘vitrified forts’. During vitrification, the granular wall rocks partially melt, sinter viscously and densify, reducing inter-particle porosity. This process is strongly dependent on the solidus temperature, the particle sizes, the temperature-dependence of the viscosity of the evolving liquid phase, as well as the distribution and longevity of heat. Examination of the sintering behaviour of 45 European examples reveals that it is the raw building material that governs the vitrification efficiency. As Iron Age forts were commonly constructed from local stone, we conclude that local geology directly influenced the degree to which buildings were vitrified in the Iron Age. Additionally, we find that vitrification is accompanied by a bulk material strengthening of the aggregates of small sizes, and a partial weakening of larger blocks. We discuss these findings in the context of the debate surrounding the motive of the wall-builders. We conclude that if wall stability by bulk strengthening was the desired effect, then vitrification represents an Iron Age technology that failed to be effective in regions of refractory local geology.

VOCs transport with VOCs-adsorbing particles under VOCs emission from carpet

Many kinds of Volatile organic compounds (VOCs) emitted from building materials can deteriorate indoor air quality. Thus, it is essential to investigate how VOCs transport and how the airside VOCs concentration can be reduced. In order to remove airside VOCs, activated carbon particles can be used. This paper investigates the effect of activated carbon particles on the airside concentration of VOCs emitted from a new carpet in a room. A new numerical method for predicting airside VOCs concentration under the presence of activated carbon particles is developed, which includes spatially repeated iteration to get the transient airside VOCs concentration in association with the activated carbon particles’ adsorption of VOCs. The current numerical model is validated over an existing experimental result. Commercial software FLUENT 12.0 is adopted to solve the continuity, momentum, turbulence and concentration equations in two main cases under the situations with and without considering particle deposition. Numerical results show that the transient concentrations of VOCs in the air reach peaks, decay rapidly, drop slowly and remain in the room for a long time. When the particle concentration is at a higher level, the decrease in airside VOCs concentration is more notable. The concept proposed in this study can be utilized, with the use of activated carbon particles, to enhance the emission rate of VOCs in raw building materials before they are furnished in newly built indoor spaces.

The Photon Attenuation Coefficients of Building Materials Containing with Lead Carbonate (PbCO<sub>3</sub>)

The total mass attenuation coefficient (μ/ρ, cm2 g-1) of gamma-ray for building materials containing with Lead Carbonate (PbCO3) have been studied. The raw building material have cement, sand and stone in the ratio 1 : 2 : 4. The raw material was mixed with 30% of PbCO3 to be used as the sample material. The mass attenuation coefficient of the raw material has been calculated by theoretical approach using WinXCom program for the photon energy band from 1 keV to 100 GeV. The composition of sample material was analyzed by energy dispersive X-ray fluorescence spectrometer (EDXRF). The variations of mass attenuation coefficient are shown graphically and compared with that of standard shielding concretes. It was found that the sample building material has higher value of mass attenuation coefficient than standard shielding concretes at energy zone above 2–7 keV, 90–800 keV and 5 MeV–100 GeV.

Estimation of radioactivity level and associated radiological hazards of limestone and gypsum used as raw building materials in Rawalpindi/Islamabad region of Pakistan

This study was undertaken to asses the radioactivity level of limestone and gypsum and its associated radiological hazard due to the presence of naturally occurring radioactive materials. Representative samples of limestone and gypsum were collected from cement factories located in the Rawalpindi/Islamabad region of Pakistan and were analysed by using an N-type high-purity germanium detector of 80 % relative efficiency. The average activity concentration of (40)K, (226)Ra and (232)Th were 60.22±3.47, 29.25±5.23 and 4.07±3.31 Bq kg(-1), respectively, in limestone and 70.86±4.1, 5.01±2.10 and 4.49±3.1 Bq kg(-1), respectively, in gypsum. The radiological hazard parameters radium equivalent activities, absorbed dose rate in air, external hazard index, internal hazard index, annual effective dose equivalent, gamma index and alpha index were computed. The results of the average activity concentrations of (40)K, (226)Ra and (232)Th and radiological hazard parameters were within the range of the reported average worldwide/United Nations Scientific Committee on the Effect of Atomic Radiation values. It is concluded that limestone and gypsum used in the Rawalpindi/Islamabad region does not pose any excessive radiological health hazard as a building raw materials and in industrial uses.

Impact sound insulation technique using corn cob particleboard

A low technological corn cob particleboard has been under research by this research team. It intends to be affordable and sustainable. So far, some of its assessed material properties (e.g. density, fire resistance, durability, thermal conductivity, compression and bending strengths, and impact resistance) suggest adequacy of this product for several building applications, such as a thermal insulation product, a light weight partition wall, a ceiling coating, or as indoor doors, among other possibilities. However, proper acoustic insulation performance is also a fundamental property required for most of the above identified building applications. Therefore, this paper is focused on evaluating the impact sound insulation potential of the proposed particleboard. At this stage, impact sound insulation tests have been performed in which the acoustic insulation gain of a pavement reinforced acoustically by a 3cm thick corn cob particleboard was assessed. The obtained acoustic insulation gain was then compared with the respective ones of traditional sound insulation products (e.g. glass wool and expanded polystyrene) and also with different alternative natural sound insulation products (e.g. kenaf, coco fibre, sheep wool, cork and cellulose). The obtained results indicate that the proposed product may also have an interesting acoustic behaviour for building purposes. This conclusion is even more interesting taking into account that corn cob is a natural, organic, renewable and local raw building material.

Characterization of corn cob as a possible raw building material

Usually, the corn cob is considered an agriculture waste. This natural and organic waste material may be used in the industry, in general, and in the building industry, in particular. The work presented in this paper was developed in order to give a contribution to the knowledge of this material, by attempting to describe and assess its macrostructure and microstructure, elementary chemical composition, density, water absorption, fire resistance and thermal insulation capacity. These properties of the corn cob were compared with the corresponding ones of the most common thermal insulation products applied in the Portuguese building industry, which are extruded polystyrene (XPS), expanded polystyrene (EPS), cork and expanded clay. Several similarities were found when comparing the properties of these materials, in particular between the corn cob and the cork, which suggests that the corn cob may be used as a raw material to process thermal insulating products, light partition walls, ceiling coating, indoor doors and furniture, among other possible applications. The obtained results can also contribute to a more environmentally friendly building industry.

Behaviour of drystone retaining structures

Drystone walling is an ancient form of wall construction, used worldwide wherever there is an abundance of raw building materials. However, very little research has been conducted on these structures, making their analysis difficult. As part of an ongoing investigation, four full-scale drystone retaining walls were built and tested to failure in a bespoke outdoor test laboratory. Through the course of the testing, the distinctive bulge patterns that are found in many in situ walls were successfully recreated. This paper describes the set-up of the test laboratory and instrumentation used, in addition to the proceedings of each wall test. Initial findings of the project tests and a discussion regarding the underlying reasons behind bulging in drystone walls are presented.