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Traditionally constructed wetlands face significant limitations in treating tailwater from wastewater treatment plants, especially those associated with sugar mills. However, the advent of novel modified surface flow constructed wetlands offer a promising solution. This study aimed to assess the microbial community composition and compare the efficiencies of contaminant removal across different treatment wetlands: CW1 (Brick rubble, lignite, and Lemna minor L.), CW2 (Brick rubble and lignite), and CW3 (Lemna minor L.). The study also examined the impact of substrate and vegetation on the wetland systems. For a hydraulic retention time of 7 days, CW1 successfully removed more pollutants than CW2 and CW3. CW1 demonstrated removal rates of 72.19% for biochemical oxygen demand (BOD), 74.82% for chemical oxygen demand (COD), 79.62% for NH4 +-N, 77.84% for NO3--N, 87.73% for ortho phosphorous (OP), 78% for total dissolved solids (TDS), 74.1% for total nitrogen (TN), 81.07% for total phosphorous (TP), and 72.90% for total suspended solids (TSS). Furthermore, high-throughput sequencing analysis of the 16S rRNA gene revealed that CW1 exhibited elevated Chao1, Shannon, and Simpson indices, with values of 1324.46, 8.8172, and 0.9941, respectively. The most common bacterial species in the wetland system were Proteobacteria, Spirochaetota, Bacteroidota, Desulfobacterota, and Chloroflexi. The denitrifying bacterial class Rhodobacteriaceae also had the highest content ratio within the wetland system. These results confirm that CW1 significantly improves the performance of water filtration. Therefore, this research provides valuable insights for wastewater treatment facilities aiming to incorporate surface flow-constructed wetland tailwater enhancement initiatives. [ABSTRACT FROM AUTHOR]

Recently, the prevailing strategy has been to dispose of building waste safely. The objective of this research is to study the feasibility of using crushed bricks (CB) and ceramic waste (CW) along with PEG 400 to produce low-cost concrete with acceptable properties, preserve natural resources, and protect the ecosystem from waste. Nine concrete mixtures were produced. CB and CW were used as a partial substitution for coarse aggregate by 20%, 40%, and 60% of its weight. Three curing methods were utilized: air curing, water curing, and self-curing with Polyethylene glycol 400 (PEG 400). Various properties of hardened concrete were investigated, such as compressive strength, flexural strength, splitting tensile strength, elastic modulus, water absorption rate, water sorptivity, and density. The results demonstrated that the compressive strength, flexural strength, splitting tensile strength, and elastic modulus of CW mixtures were greater than those of CB mixtures. The mix with 40% CW and PEG 400 achieved the highest compressive strength, flexural strength, splitting tensile strength, and elastic modulus by 19.42%, 23.5%, 23.94%, and 27.6%, respectively, with respect to the reference mix cured in water. The workability of CB and CW mixtures improved, and slump values increased with the increasing ratio of CB and CW. The water sorptivity reduced until the replacement ratio reached 40% of dolomite with CB and CW. SEM images indicated that the pores decreased, and more crystals of calcium silicate hydrate formed in a mixture with 40% CW and PEG 400 compared to the reference mix.

Traditionally constructed wetlands face significant limitations in treating tailwater from wastewater treatment plants, especially those associated with sugar mills. However, the advent of novel modified surface flow constructed wetlands offer a promising solution. This study aimed to assess the microbial community composition and compare the efficiencies of contaminant removal across different treatment wetlands: CW1 (Brick rubble, lignite, and Lemna minor L.), CW2 (Brick rubble and lignite), and CW3 (Lemna minor L.). The study also examined the impact of substrate and vegetation on the wetland systems. For a hydraulic retention time of 7 days, CW1 successfully removed more pollutants than CW2 and CW3. CW1 demonstrated removal rates of 72.19% for biochemical oxygen demand (BOD), 74.82% for chemical oxygen demand (COD), 79.62% for NH4+-N, 77.84% for NO3−-N, 87.73% for ortho phosphorous (OP), 78% for total dissolved solids (TDS), 74.1% for total nitrogen (TN), 81.07% for total phosphorous (TP), and 72.90% for total suspended solids (TSS). Furthermore, high-throughput sequencing analysis of the 16S rRNA gene revealed that CW1 exhibited elevated Chao1, Shannon, and Simpson indices, with values of 1324.46, 8.8172, and 0.9941, respectively. The most common bacterial species in the wetland system were Proteobacteria, Spirochaetota, Bacteroidota, Desulfobacterota, and Chloroflexi. The denitrifying bacterial class Rhodobacteriaceae also had the highest content ratio within the wetland system. These results confirm that CW1 significantly improves the performance of water filtration. Therefore, this research provides valuable insights for wastewater treatment facilities aiming to incorporate surface flow-constructed wetland tailwater enhancement initiatives.

Recycling demolition waste materials as construction materials offers environmental as well as economic benefits by protecting virgin materials and reducing overall costs of project. This paper presents an experimental investigation on flexural behavior of reinforced concrete beams made with coarse aggregate fully 100 % or partially 50 % replaced by crushed concrete or crushed bricks as waste materials in full or half depth of beams. Nine beams are tested over a simply supported span, one with full natural aggregate as reference and the others with waste aggregate in different ratios and depths (four with crushed concrete and four with crushed bricks). Results show that the structural behavior of beams with waste aggregates is similar to the reference beam with strength reduction of 3 – 20 %. Crushed concrete beams show higher strength and stiffer behavior (in general) than crushed bricks. Also, increasing replacement ratio from 50 % to 100 % or replacement depth from half to full reduced strength by about 10 % only which encourage utilizing maximum quantity of waste construction materials in concrete structures.

The increasing volume of waste and the requirements of sustainable development are the reasons for the research on new waste management concepts. The research results presented in this paper show the effect of recycled aggregate on the selected properties of cement concrete. The aggregates obtained from three types of wastes are tested: recycled concrete paving, crushed ceramic bricks, and burnt sewage sludges. The recycled aggregates replaced 25% and 50% of the volume of the fine aggregate. The tested aggregates worsen the concrete mixes' consistency and decrease, to some extent, the compressive strength of the concrete. However, the tensile splitting strength of the concrete with recycled aggregates is similar to that of the reference concrete. Using recycled aggregates worsens the tightness of the concrete, which manifests itself by increasing water penetration depth. The thermal properties of concrete are slightly affected by the type and content of the recycled aggregate. Considering the expected improvement in recycled aggregate processing, they can be an alternative to natural aggregates. Using recycled aggregates in cement concrete requires extensive studies to search for ways to increase their possible content without worsening concrete performance. [ABSTRACT FROM AUTHOR]

The increasing volume of waste and the requirements of sustainable development are the reasons for the research on new waste management concepts. The research results presented in this paper show the effect of recycled aggregate on the selected properties of cement concrete. The aggregates obtained from three types of wastes are tested: recycled concrete paving, crushed ceramic bricks, and burnt sewage sludges. The recycled aggregates replaced 25% and 50% of the volume of the fine aggregate. The tested aggregates worsen the concrete mixes’ consistency and decrease, to some extent, the compressive strength of the concrete. However, the tensile splitting strength of the concrete with recycled aggregates is similar to that of the reference concrete. Using recycled aggregates worsens the tightness of the concrete, which manifests itself by increasing water penetration depth. The thermal properties of concrete are slightly affected by the type and content of the recycled aggregate. Considering the expected improvement in recycled aggregate processing, they can be an alternative to natural aggregates. Using recycled aggregates in cement concrete requires extensive studies to search for ways to increase their possible content without worsening concrete performance.

Brick from demolitions can be reused as recycled aggregate in the elaboration of concrete, helping to care for the environment by reducing the use of raw materials. The present work aims to achieve a systematic review on the use of crushed bricks in concrete, in order to synthesize the results obtained and discuss the possibility of using this recycled material in different areas of construction. A review of 51 articles indexed between the years 2015 to 2021 was made, distributed as follows: 41 articles are from Scopus and 10 from Sciencedirect, which show how crushed brick influences the properties of concrete. The reviews of the results found that recycled brick aggregates (RBA) generate a deficiency in compressive strength and higher porosity as opposed to natural aggregate (NA). [ABSTRACT FROM AUTHOR]

Extensive green roofs substrates should meet a list of physicochemical and biochemical requirements to be used as a basis for plant growth: high water holding capacity, good aeration, low bulk density, and proper drainage are some of them. In recent years, the impact of different organic matter doses and the substrate depth on the subsequent plant growth have been deeply studied. By contrast, there are not many publications about the effect of the inorganic component of these substrates on plant development and C and N sequestration potential by the green roof system, and even more under semi-arid Mediterranean conditions. Four substrates were made by mixing the same compost, at 10% by volume, with different inorganic materials: CsB (compost, silica sand, and crushed bricks; 1:1:8), CB (compost and crushed bricks; 1:9), CSB (compost, clay-loam soil, and crushed bricks; 1:1:8), and CsS (compost, silica sand, and clay-loam soil; 1:1:8). These were placed, a depth of 10 cm, on “cultivation tables” in an experimental farm located in the SE of Spain. Two native species were sown in each substrate: Lotus creticus and Asteriscus maritimus . Physicochemical, nutritional, and biochemical properties of the substrates as well as the plant development were evaluated during a 10-month experiment. The CsB and CSB mixtures had good physicochemical properties (high porosity and acceptable water holding capacity) although the levels of C, N, and humic substances were higher in the soil-containing substrates than in the CB and CsB mixtures. The hydrolytic enzyme activity was also promoted in these mixtures. The plant growth pattern showed differences regarding the inorganic composition of the substrate; L. creticus had superior development in the CsB substrate and A. maritimus was able to grow in all tested substrate mixtures, although its cover was low, being a more versatile candidate to establish a green roof cover. The greatest C and N sequestration potential was achieved by the CsS mixture, reaching 1.06 kg TC m −2 of green roof substrate. Therefore, substrate composition impacts the growth of native plant species as well as the C and N sequestration by the green roof system. [ABSTRACT FROM AUTHOR]

Information on the effects of incorporating fine recycled ceramic aggregates on concrete's durability is very scarce. This paper presents an experimental study using aggregates sourced from crushed red clay ceramic bricks (CBAs) and sanitary ware (SWA). Different concrete mixes were produced where the fine natural aggregate fraction was partially or fully replaced (20%, 50% and 100%, by volume) by each of these materials. Shrinkage, water absorption by immersion, water absorption by capillary action, carbonation and chloride ion penetration tests were carried out. Results show that using fine CBA provides better performance in terms of water absorption by capillarity and chloride ion penetration, contrarily to shrinkage, water absorption by immersion and carbonation penetration. Using fine SWA leads to a similar performance in terms of shrinkage, but all other properties are significantly and detrimentally affected. Notwithstanding the increased water requirement due to the high absorption capacity of CBA and the formation of agglomerated particles with SWA, this paper shows that a judicious use of these materials may allow the production of adequate structural concrete; in mixes with SWA the use of superplasticizers is a very effective approach in preventing the formation of clusters, even providing a better performance than the control concrete. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to demonstrate that it is possible to make precast concrete floor blocks with more than 50% replacement of natural aggregate with recycled aggregate made with crushed clay bricks and roof tiles. In first phase of the research, the physico-mechanical properties of concrete with recycled and with natural aggregate were tested. The second phase explored the properties of precast concrete floor blocks. Their geometrical, mechanical, thermal and acoustic properties were determined. Based on experimental research it can be stated that it is possible to make precast concrete floor blocks with recycled aggregate with the fulfilled thermal, cost and environmental requirements. [ABSTRACT FROM AUTHOR]

The study of the growth of several Mediterranean endemic plant species in new artificial substrates is becoming necessary for seeking alternatives in green roof design in Mediterranean regions. In this regard, we evaluated the growth of six native species on three different artificial substrates. These species were Silene vulgaris, Silene secundiflora, Crithmum maritimum, Lagurus ovatus, Asteriscus maritimus , and Lotus creticus . A mixture of a green compost with a clay–loam soil (C + Soil), the same compost mixed with expanded clay (C + Clay), and the compost mixed with crushed bricks (C + Bricks) – all in 1:4 volumetric proportions – were the assayed substrates. Physichochemical and biochemical properties were studied in each mixture at the beginning and end of a three-month assay. Besides, the germination and growth of all plant species in each substrate type were evaluated. The mixtures C + Clay and C + Bricks showed greater porosity than C + Soil, leading to a high root: shoot biomass ratio in all species tested. Conversely, the mixture C + Soil possessed better biochemical properties (higher humic substances content and enzyme activity), but they decreased with experimental time. Contrarily, the humic substances and the dehydrogenase activity increased in the most porous mixtures. Regarding plant behaviour, S. vulgaris and L. ovatus showed greater germination and growth than the other species, especially above C + Clay and C + Bricks mixtures. Accordingly, we strongly recommend the use of lightweight and highly porous substrates as the basis for the growing of Mediterranean native herbaceous species, since they specially enhance their root development. The combined use of perennials and annuals species in that kind of substrates could provide a permanent plant cover in a green roof scenario. [ABSTRACT FROM AUTHOR]

The Lucknow monuments of the 18th century are large masonry structures built using thin burnt-clay bricks (Lakhauri) and lime-crushed brick aggregate (surkhi) mortars. Investigations were carried out to characterize the engineering properties of old masonry materials and new mortars being used for renovation work. Mechanical properties of reclaimed Lakhauri bricks were found comparable to good quality contemporary bricks of the region. Moreover, X-ray diffraction (XRD) and scanning electron microscopy–energy dispersive X-ray spectrometry (SEM-EDS) analyses indicated that mineralogical composition is not too different, except for few minerals. The lime-surkhi mortar used in old masonry work was found to be lime-rich with binder to aggregate ratio of approximately 1:2 to 3 by volume. The renovation mortar had poor hydraulic property as compared to old mortars indicated by thermal gravimetric analysis–differential thermal analysis (TGA-DTA) analyses. The compressive behavior of multi-wythe recreated Lakhauri masonry prisms was characterized with low compressive strength, low modulus, and significant deformability which result in lower stress demands imposed on the structural assemblages by various environmental forces. [ABSTRACT FROM PUBLISHER]

The development of artificial substrates or Technosols to be used in green roofs is increasing nowadays. Microbiological and biochemical aspects should be taken into consideration when designing an artificial substrate, to assure the quality of the chosen materials and the future plant development. Our purpose is to develop an appropriate substrate consisting of a mix of organic and inorganic residues. We used green compost mixed, on the one hand, with a clay-loam soil and, on the other, with crushed bricks, in two volumetric proportions (20:80 and 50:50). An incubation experiment was conducted to study the short-term evolution of physicochemical, biochemical, and microbiological substrates characteristics. Most of the enzymatic activities (β-GLA, URA, and APA) and microbiological parameters determined (microbial respiration and qCO2) showed that the compost-soil mixtures were able to maintain biochemical processes during the incubation time. In contrast, the compost-brick mixtures possessed appropriate physicochemical properties (60% of porosity, good aeration conditions, and higher oxidative enzyme activities; PPO and POD) but they presented less nutrient content (TOC, TC, and TN) and reduced microbial activity in general, which are of paramount importance in plant growth. Moreover, the PLFAs analysis (phospholipid fatty acids) showed that compost-brick may support a bacterial community throughout the experiment while in compost-soil mixtures there was further development of fungi, although its content decreased with incubation time. We conclude that both the substrate composition and the compost dose affect the development of microbial biomass at structural and functional levels. Therefore, physicochemical properties along with biochemical and microbiological aspects should be considered to design a suitable substrate for a future plant development. [ABSTRACT FROM AUTHOR]

The investigation reported in this paper is carried out to study the feasibility of using crushed bricks to substitute the coarse aggregate (gravel) in concrete. Two types of concrete mixing are prepared. The first one is a mixture of 1:2:4 without crushed bricks and is used as a reference mixture .The second one is made of different weight of crushed bricks (as a percentage from the weight of the coarse aggregate). A total of 30 numbers of concrete specimens are casted with and without crushed bricks and tested under compression and split tension as per relevant to British standard specifications. Test results indicated that using crushed bricks reduces the strength of concrete. Also, the percentage of water to cement ratio increases for constant slump when the percentage of crushed bricks increased.

Abstract: This paper reports on a study of the behavior of plain concrete made with mixed recycled coarse aggregate, i.e., recycled aggregate with a high percentage of fired clay (brick and similar) waste. The parameters studied were: workability, density, compressive strength, longitudinal modulus of deformation, Poisson ratio, depth of water penetration under pressure and the stress–strain diagram. Control concretes (containing natural coarse aggregate only), concretes with half natural and half recycled aggregate and concretes with recycled coarse aggregate only were prepared to conduct the respective tests. [Copyright &y& Elsevier]