Total Sand Research Articles

Interference effect of configuration parameters of vertical sand-obstacles on near-surface sand transport

This study investigates the impacts of height (H) and porosity (P) on the structural properties of wind-driven sand flux in vertical sunflower straw sand-obstacles. We conducted an experiment on sand transport within barriers of various configurations within a 1 m proximity to the surface. In tandem, we monitored wind velocity and direction within the barriers, analyzed total sand transport rate, sand-blocking effects, and cumulative sediment transport rate heights for various parameter configurations, and devised a best sand transport flux model for use within the sand-obstacle. The efficacy of vertical sunflower stalk sand-obstacles in mitigating sand movement has been demonstrated to fall within the range of 37.26%–92.31%. This study reveals a significant correlation between barrier height and porosity in achieving this effect (p < 0.05). High and densely configured sand-obstacles lead to an accumulation of intercepted sand material in front of the front row of the sand-obstacle. In contrast, low and sparsely arranged sand-obstacles exhibit a delayed state of sand material accumulation. Furthermore, with an increase in the height of the obstacle and a decrease in porosity, there is a diminishing trend in the sand transport rate within the obstacle. Concurrently, the height of sand transport within the barrier exhibits an upward trend. A three-parameter exponential function has been employed to more precisely simulate the wind-sand flow structure characteristics within a 1-m height range of the barrier. These research findings contribute to an enhanced understanding of the impact of different vertical sand-obstacle configurations on near-surface wind-driven sand transport patterns in active desert areas. Moreover, they furnish both theoretical underpinnings and practical guidance for the scientific configuration of vertical sand-obstacles.

Aeolian Sand Erosion and Deposition Patterns in the Arid Region of the Xiliugou Tributary on the Upper Reaches of the Yellow River

Surveys show that rivers worldwide transport an annual sediment load of 15 billion tons into the sea, with the Yellow River Basin alone contributing 1.6 billion tons of sand. Therefore, understanding the wind and sand dynamics in the Yellow River Basin is crucial to ensuring the safe development of similar basins across China and the world. This study investigated the midstream wind and sand area of the Xiliugou tributary, a part of the upper Yellow River. Sand transport flux at 0–50 cm height on various underlying surfaces of the basin was measured using a stepped sand collector combined with an anemometer. Then, the amounts of wind and sand entering the Yellow River were estimated using a function model based on the measured factors. The particle size composition of wind-eroded sand was further analyzed to better understand the principles of wind and sand erosion and accumulation in the basin. The results show that the sand transport flux per unit area varies significantly across different underlying surfaces. The vertical change in sand transport rate on the basin’s surface shows that the total sand transport rate is an exponential function of wind speed. Based on this relationship, the total annual average wind and sand entering the Yellow River basin via the Xiliugou tributary was estimated to be approximately 8.09 × 105 t. Controlled by the basin’s unique geography, sand source, and human activities, the particle size composition of wind-eroded sand distinctly differs between the east and west sides of the river channel, exhibiting a “wind-blown mud and water-washed sand” pattern. The Yellow River basin still faces significant ecological security hazards. Understanding the coupling relationship between desert-basin-sand and wind is the foundation for effectively controlling wind and sand flow into the Yellow River Basin.

Development of low-carbon and cost-effective ultra-high performance concrete using carbonated recycled fine aggregate

This paper studied the influence of carbonated recycled fine aggregate (RFA) on mechanical and microstructural performance of ultra-high performance concrete (UHPC), aiming to develop a low-carbon and cost-effective UHPC. This includes the changes in strength, hydration kinetics, RFA-to-paste interfacial microstructure, and pore structure with the use of carbonated RFA. The environmental and economic effect of using carbonated RFA in UHPC is evaluated. The RFA content was investigated at 0–30%, by mass of total sand. Experimental results showed that a reduction greater than 10% in crushing index and water absorption of RFA was achieved by carbonation. The increase of carbonated RFA content from 0 to 30% led to 45% reduction in autogenous shrinkage of UHPC. The use of 20% uncarbonated RFA resulted in 12% and 10% reduction in 28-d compressive and flexural strengths, respectively, while such use of carbonated RFA can secure similar 28-d compressive and flexural strengths compared to those without RFA. Despite the reduced cement hydration, the use of carbonated RFA can secure a denser RFA-to-paste interfacial microstructure and refine the pore structure of UHPC compared to those made with uncarbonated RFA, given the chemical bonding and nucleation effect of carbonated RFA. Moreover, the use of 20% carbonated RFA can enable 5% decrease in the Global Warming Potential value evaluated by life cycle assessment compared to that without RFA. Such use of RFA led to a decrease greater than 15% in UHPC cost. This indicated the low-carbon and cost-effective characteristics of the developed UHPC made with carbonated RFA.

Integrated Optimization System Improves Hydraulic Fracturing Operations

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 209127, “Efficiency and Effectiveness—A Fine Balance: An Integrated System To Improve Decisions in Real-Time Hydraulic Fracturing Operations,” by Somnath Mondal, SPE, Ashan Garusinghe, and Sebastian Ziman, Shell, et al. The paper has not been peer reviewed. _ In the complete paper, the authors demonstrate the need to balance optimizing fracture efficiency with effectiveness; present an integrated system for fracturing optimization using real-time, historical data along with organizational knowledge; and discuss the challenges and key considerations of setting up such a system, along with examples of large, untapped potential that can be unlocked with data science. Introduction Currently, most third-party fracture-monitoring solutions do not provide a true fracture-optimization platform that goes beyond fracture monitoring and efficiency or cost analytics. Without consideration for creating effective fracture geometries and good stimulation distribution, this may lead to poor resource recovery. Integrated fiber-optic diagnostics data have also shown that perforation-cluster screenout signatures sometimes can be observed in the surface-treatment data. Historical analysis of surface-treatment data has revealed that perforation-cluster screenout signatures are widely observed in other basins (Fig. 1). Cluster screenouts lead to severe nonuniformity in stimulation distribution. These examples demonstrate the need for including effectiveness considerations in any real-time fracture-optimization algorithm. The Completions Automation and Remote Technology (CART) Center was set up in 2017 by the operator to monitor and optimize all shale-fracturing operations remotely across multiple basins. The Center is staffed by consultants whose main role is to provide input directly to the engineer on site to optimize each treatment. Currently, this remote model relies on the experience of the consultant to know when and where to provide the right input. Data Preprocessing Modularity is a key component of the authors’ framework. The first step is to process new data, calculating important statistics used in historical analysis. Calculations to generate statistics used within the models also are performed. Models can be applied sequentially within this framework, posing no problems with regard to interdependency. As data are fed into the framework, automated analyses are performed to detect the start and end of a stage in real time. Instead of opting for a complex deep-learning algorithm, the authors implemented a simpler rule-based model to improve operational efficiency of the tool. At each new time stamp, the injection rate and pressure are evaluated to determine if fracturing operations have commenced; should the flow rate fall back to near zero, the framework will reset itself if this was simply a testing period of the stage or counts the stage as ended if the total sand pumped is more than the minimum required for the stage. Easy or Hard Stage A fracturing stage can be classified as “easy” or “hard” depending on how easily injectivity can be achieved and maintained. Engineers try to classify a stage as early as possible to decide how readily a stage will accept sand. The complete paper presents a work flow to assist engineers in the early classification of these stages.

Physical characterization of the weathering profile over a sheared, biotite-muscovite granite in Peninsular Malaysia

The weathering profile can be separated into an upper, 11.8 m thick pedological soil (zone I) comprising gravelly clayey sands and a lower, >31.9 m thick saprock (zone II) consisting of gravelly silty sands with distinct preservation of the minerals, textures and structures of the original granitic bedrock material and mass. Zone I can be separated into A, B and C soil horizons, whilst zone II can be differentiated into sub-zones IIA, IIB, IIC and IID based on differences in preservation of relict structures and content of core-boulders. The earth materials of zone I represent rock mass weathering grade VI, whilst those of sub-zones IIA and IIB represent grade V, and those of sub-zones IIC and IID represent grades IV and III respectively. Constant volume samples show the earth materials to have variable dry unit weights (11.98 to 17.66 kN/m3), but a limited range in specific gravity (2.62 to 2.70) due to similar primary and secondary minerals. The zone I earth materials have relatively large clay contents (>19%) and are more porous (33% to 55%) than those of zone II (36% to 44%) which have large silt contents (>23%). Sand contents are more variable (23% to 44%) though relatively large total sand and gravel contents (37% to 68%) point to the original, coarse grained granitic bedrock. Increasing clay contents (of kaolinite and illite) up the profile, and a corresponding decrease in silt contents (of mainly sericite), reflect increasing alteration of the bedrock; a feature also shown by increasing values of the textural weathering index (Iw). Distinct preservation of granitic textures and structures in saprock (zone II) indicate in situ alteration of bedrock; weathering resulting from gradual lowering of an unconfined groundwater table.

Analysis of Factors Affecting Railway Settlement of Embankment Section due to Liquefaction Using 1-g Shaking Table Model Tests

Herein, 1-g shaking table tests were performed under test by changing the embankment height and non-liquefiable layer thickness below the embankment for the same input seismic load. Accelerometers, pore water pressure transducers, and linear variable differential transformers were embedded inside the foundation ground or installed on the embankment surface to measure their responses to shaking. The testing procedure for analyzing the behavior of a two-dimensional embankment-ground system and well-documented experimental data are presented. The results show that the settlement of the railway embankment placed on the liquefiable sand ground due to ground liquefaction is greatly affected by the embankment height and non-liquefaction layer thickness, which determine the degree of liquefaction and lateral flow of the foundation ground. The embankment settlement increased with the embankment height due to the liquefaction of the ground and increased by twice the settlement of the ground without embankment when the embankment height was approximately 20% of the total liquefiable sand layer. Moreover, the settlement was reduced by over 20% compared to that without a layer when the layer thickness was 50% of the embankment height. Furthermore, the settlement decreased to a negligible level when it was approximately 1.5 times the height of the embankment.

The effect of double-row wing bag sand barrier on wind prevention and sand fixation: wind tunnel simulation and field verification

Introduction: Most of the sand fixation technologies utilized locally and internationally are static or dynamic, making it challenging for a single sand fixation mode to function in a harsh environment. Therefore, the development of a sand fixation mode that combines resistance and consolidation has emerged as a trending topic in sand control research. Our team developed the wing bag sand barrier, which is a static and dynamic combination of sand fixation mode.Methods: In this study, we examined the characteristics of airflow velocity field and sand resistance near double-row wing bag sand barrier under different wind conditions to screen out the optimal mode of wing bag sand barrier. The analyses were conducted under nine configuration modes through the wind tunnel simulation experiment and the field experiment.Results: The inflection point of the airflow was always 5H on the windward side of the wing bag sand barrier, regardless of the wind speed. The protection range of the wing bag sand barrier with the same specifications was gradually weakened with the increase of the wind speed. However, there was an upward trend in both total sand accumulation and sand accumulation of each height layer. When the wind speed was slower than 8 m/s, the sand accumulation behind the barrier was mainly concentrated in the 0–10 cm height layer, and when the wind speed was 12 m/s, it was mainly concentrated in the 30–60 cm height layer. At the leeward side of the wing bag sand barrier, sand particles were rejected in the range of 0–30 cm; however, they were conducted in the range of 30–60 cm. The protective effect of the wing bag sand barrier simulated in the wind tunnel experiment was consistent with that of the field experiment.Discussion: For a wind speed of slower than 6 m/s, the recommended specification for the field-installed wing bag sand barrier was 25 cm × 20 cm or 30 cm × 20 cm. The specifications 25 cm × 20 cm and 25 cm × 25 cm were recommended at an inlet wind speed of 8 m/s. When the wind speed was greater than 12 m/s, the recommended specifications were 25 cm × 25 cm, 25 cm × 20 cm, and 20 cm × 25 cm.

Soil Quality Assessment of Several Kinds of Typical Artificial Forestlands in the Inner Mongolia Basin of the Yellow River

Located in the middle and upper parts of the Yellow River Basin, Qingshuihe County, Inner Mongolia, is a typical hilly and gully loess region and one of areas under the implementation of major ecological protection and restoration projects in the key ecological areas of Yellow River. Scientifically and accurately constructing a soil quality evaluation system for different types of artificial forest land and evaluating their soil quality are essential because they help optimize the structure of artificial forest land and improve the soil quality in the loess hilly area of Yellow River Basin. In this study, soil from four representative types of artificial forest land in the middle and upper reaches of the Yellow River Basin in Inner Mongolia was selected as the study object, with natural non-forest land as the control. Sixteen soil property indices in five classes, namely, soil texture, acid–base properties, moisture, pore, and nutrient, were screened using correlation analysis, minimum dataset (MDS), and principal component analysis methods, and an MDS of soil quality evaluation was constructed. Results showed that (1) the evaluation indices of artificial forest land soil quality based on the MDS included total potassium content, total phosphorus content, alkali-hydrolyzed nitrogen content, total nitrogen content, sand content, moisture content, and non-capillary porosity. (2) No significant differences were observed in the soil quality index among the MDS, total dataset, and significant dataset (SDS), all of which exhibited significant positive correlations. (3) The soil quality of the different types of forest land was sorted from high to low as follows: mixed coniferous and broad-leaved forests, larch forests, mixed arbor and shrub forests, Armeniaca sibirica forests, and natural non-forest land.

Quantifyting research on the protection effect of a desert‒oasis ecotone in Dunhuang, Northwest China

A desert‒oasis ecotone is an important barrier for an oasis, although few studies have attempted to investigate and quantify the protection that it offers. In this paper, a portable wind-monitoring system, fixed automatic weather-monitoring instrument, and eight-directional sand-collecting instrument were used to study the protection benefits offered by a desert‒oasis ecotone in Dunhuang, Northwest China. The data showed that a desert–oasis ecotone can effectively reduce regional wind speed, sand-driving wind speed, drift potential, and wind-blown sand activity, while also increasing the aerodynamic roughness length in order to prevent erosion driven by surface winds. When passing through the ecotone, the percentage of sand-driving wind reduced from 21.0% to 2.98%, and the resultant drift potential was reduced from 135.67 to 14.94 VU. In the study area, the resultant sand-driving wind mainly traveled southwards, and the frequency of sand-driving winds decreased commensurately with increases in vegetation cover and desert–oasis ecotone width. In 2015, the total wind-blown sand fluxes were 3.90 kg m−1 d−1 in the desert environment, 1.09 kg m−1 d−1 in the desert‒oasis ecotone, and 1.08 kg m−1 d−1 in the oasis. The wind-blown material's grain size in the desert region was dominated by medium sand, which comprised 47–60% of the total; by contrast, wind-blown materials in the desert‒oasis ecotone and oasis were dominated by fine sand, with proportions of 51–63% and 52–70%, respectively. The protection offered by a desert‒oasis ecotone is related to aerodynamic roughness length, distance of airflow across the ecotone, and wind speed. Among them, aerodynamic roughness length and distance of airflow across the ecotone were positively correlated with the level of protection offered, while wind speed showed a negative correlation. We also present a mathematical relationships between these variables that can provide a scientific basis for determining the optimum width to develop desert–oasis ecotones in arid regions.

Free-living marine nematode communities in Rhizophora mucronata Lam. (Rhizophoraceae) forest at Mida Creek, Kenya

Nematodes are among the most abundant organisms in marine ecosystems where they play a critical role in nutrient cycling, provision of nourishment to the higher organisms in the food web, pest control, and act as disease-causing vectors. This study determined the abundance and community structure of nematodes in three plots of Rhizophora mucronata forest stand at Kirepwe Macho and Dabaso sites at Mida Creek, Kenya. Replicated sediment samples were randomly collected from one forest plot in Kirepwe Macho and two plots in Dabaso during the months of January and April 2011. Total organic matter, sand and silt proportions were not significantly different across the study sites and between January and April. A total of 90 and 81 nematode genera were encountered in the month of January and April, respectively. At both sampling times, the nematode community was dominated by Terschellingia (20.5 % - 15.3 %) and Paracomesoma (10.6 % - 6.6 %). The Shannon-Weiner diversity index was relatively high in the three forest plots both in January and April ranging from 2.76 to 3.40. There was no significant difference in nematode community assemblage within sites (p > 0.05, 0.901) but there were differences between sampling time (p > 0.05, 0.001). The results showed that the three sites had similar nematode community structure suggesting that the three Rhizophora mucronata mangrove forest plots did not differ in terms of nematode generic composition even though the plots were not all close to each other.

Spectral signature for quality assessment of anchovy fish meal (Engraulis Ringens) using Partial Least Squares

Fishmeal is one of the most important foods for the aquaculture, livestock and poultry sectors in Latin America and the world. However, one of the constraints in the fishing industry is to measure online the physicochemical composition of this product and ensure its quality. In this study, the spectral signature of anchovy fish meal (Engraulis Ringens) has been obtained in wavelengths from 400 to 900 nm and has been related to its values of Protein, Ash, Moisture, Fat, Free Fatty Acids (FFA), total volatile basic nitrogen (TVB-N), sand, histamine and antioxidant remnant (REM.A/O). To analyze these relationships has been used the regression of Partial Least Squares (PLS) finding the best results to determine the Protein, Fat, Moisture and with some accuracy TBVN and Histamine. In addition, the most important spectral ranges have been identified for the calculation of the estimates. With these results we have a model to determine the physicochemical composition of anchovy fish meal based on the spectral signature that could be implemented in automatic systems for process control.

English

Soils in floodplain ecosystems are sedimentary and subject to removal, transport, and deposition processes caused mainly by the water cycle, contributing to frequent variations in landscape patterns and continuous transformation of the floodplain environment. Given the constant disturbance caused by flood pulse variability, it is difficult to assess soil properties in floodplain ecosystems. Soil samples were collected at a depth of 0 to 0.10 m at floodplain and upland forest sites between Santarém and Gurupá, Pará State, Brazil. Samples were analyzed for pH H2O, aluminium, calcium, magnesium, potassium, phosphorus, total organic carbon, boron, zinc, copper, iron, manganese, sand, silt, and clay. Potential and effective cation-exchange capacity, sum of bases, base saturation, aluminum saturation, and organic matter were calculated. Data were subjected to descriptive analysis, analysis of variance, correlation analysis, and hierarchical clustering. Chemical and textural parameters differed significantly between floodplain and upland forest soils. Soil properties were highly heterogeneous. Aluminium and aluminium saturation had the highest coefficients of variation among floodplain samples, whereas pH H2O and base saturation had the lowest. It is possible to infer from the results that floodplain forest soils maintain high levels of fertility. However, this environment also shows high acidity and toxic levels of exchangeable aluminium. Key words: Flood pulse, soil fertility, floodplain ecosystem.

Bimodal Bed Load Transport Characteristics under the Influence of Mixture Ratio

The transport of a non-uniform bed load in a river is a complicated process and has enormous implications on the sediment flux and anomalous riverbed evolution. To investigate the transport characteristics of the non-uniform bed load and the related particle interactions, a real-time monitoring system of the bed load transport was developed to determine the instant transport rate and grain composition of the bed load. Doppler Velocimetry was used to synchronously measure the fluctuating velocity in high frequency. A total of 211 cases of flume experiments were conducted, focusing on non-uniform sediment with a bimodal pattern. The experimental results indicate that the random fluctuation of the bed load transport amount closely depends on the flow-intensity fluctuation caused by the turbulence burst near the bed. When the value of the flow-fluctuation peak is bigger than 2.5 σ, the coarse sands tend to incipient motion in high probability but are mostly fine sand transport when the peak is less than 1.5 σ. The transport rate of fine particles remains continuous throughout the process, while that of coarse particles is intermittent because the incipient motion mechanism of bed load sands mainly follows three modes. If the difference in diameter between the coarse and fine particles is large, the transport of coarse particles may undergo supernormal transport because of the effect of the fine particles on the coarse particles. The bed load flux of total, fine, and coarse sand present different trends with changes in the bed material composition, in which the transport rate of coarse sands and total bed load sands presents a humped curve in terms of the mixture ratio, and the optimal corresponding mixture ratio ηc is about 3:7. The optimal mixture ratio is not fixed, and it depends on the grain composition and size differential of bed material. With a proper mixture ratio, the transport rate of a non-uniform bed load is higher than the uniform bed load of related size. These findings might provide valuable support for predicting bed load transport and bed evolution in rivers.

Development of B horizon in relation to Morphological characterization and soil uniformity of some soil of northern of Iraq

The aim of the study to estimate soil uniformity and development using B horizon, Three pedons were selected within Nineveh Governorate (Rashedyia, Talafar, and Telkaif), The morphological description was carried out according to the principles followed in soil survey staff, (2014), then each pedon was divided into depths and soil samples were taken from these depths to be transferred in to laboratory for physical and chemical analysis, also some of sand particles separated by different size of sieves. The results showed an increase in sand particles values downward to the third depth and then decreased again in the fourth depth in most study sites. A parallel curve was reached at Talafar 's location within the deepest except for the fifth depth, which showed an intersection in the size of the very coarse sand (VCS), which gave a lower proportion of the rest of the depths, due to the fact that the sampling was taken advantage of the grazing area and there was no equal movement of that size between the depths, albeit slight. The values of the ratio of fine sand to the total sand showed that they were relatively lower than the values of the ratio of fine sand to coarse sand for all locations, its rates ranged (0.41 - 0.83), the standard deviation values from the arithmetic mean were less than 21% in all locations except the surface layer at Telkaif, which amounted to (30.61%).

Study on the main controlling factors of horizontal well production capacity in tight gas reservoirs in Ordos Basin

Affected by various geological factors and engineering factors such as reservoir characteristics, horizontal section length, fracturing scale, etc., there are large differences in the production capacity of the single well of the volumetric fracturing horizontal well in the 8th section of the Sulige block box, but the main control factors are not clear. To this end, taking more than 180 horizontal wells in Sulige Area A as a sample, the Pearson correlation method was used to analyze the influence of geological and fracturing construction parameters on production capacity, and the main control factors of single well production capacity were clarified. The results show that the total sand volume, total liquid volume, effective reservoir drilling rate, horizontal section length, effective number of cracks, construction displacement and average sand ratio are the main control factors affecting the production capacity of the horizontal well in the block, based on the above understanding, optimizing the fracturing construction parameters has good guiding significance for the efficient development of tight gas.

Numerical simulation study on the influence of scroll design parameters on helicopter intake system

Based on the numerical simulation theory, this paper establishes the two-phase flow calculation model of sand and air mixture in the sand control vortex tube, and combined with CFD numerical simulation, studies the influence rules of various design parameters of the vortex tube on the total pressure loss and sand dust separation efficiency of the helicopter intake system, optimizes the structural parameters of the vortex tube separator, and puts forward a set of vortex tube design method, it provides a basis for the design optimization of vortex tube.

Measuring sand content using sedimentation, spectroscopy, and laser diffraction

Sand (2,000–50 µm), silt (50–2 µm) and clay (<2 µm) have been determined by sedimentation methods (i.e., hydrometer and pipette), but increasingly laser diffraction and visible and near-infrared (vis-NIR) or mid-infrared (MIR) spectroscopy are being used. It is necessary to understand the comparability and limitations of these methods. We compared these different methods using 121 soil samples from the Central Sand Plains of Wisconsin, for total sand content as well as five sand fractions (very coarse, coarse, medium, fine, and very fine). Spectroscopic methods are not hindered by assumptions of sphericity or constant particle density; yet these model-based methods require calibration by laboratory methods that do rely on these assumptions. Vis-NIR and MIR spectroscopic model predictions of total sand content differed when calibration laboratory data were obtained from the hydrometer and pipette method. The laser method was not able to accurately measure sand fractions and the fractions were poorly to moderately predicted by vis-NIR (R2 = 0.01 to 0.61) but slightly better using MIR (R2 = 0.23 to 0.71). The hydrometer method overestimated the total sand content compared to the pipette; the laser method was only moderately correlated to both pipette and hydrometer. Spectroscopic modeling of total sand content was very good (R2 = 0.91 to 0.94), but results were affected by the laboratory calibration method and models calibrated with reference hydrometer data overestimated total sand content. We conclude that MIR predictions of sand content provide the best results, but models must be calibrated with the pipette method for soils with high sand contents.

The role of biomass bottom ash in Carbonated Reactive Magnesia Cement (CRMC) for CO2 mineralisation

This work evaluates the incorporation of biomass bottom ashes on Carbonated Reactive Magnesia Cement-based (CRMC) mortars. For this purpose, four mixtures were designed to verify the influence of biomass bottom ash as partial or total sand replacement. The specimens were moulded through static compaction pressure and submitted to an accelerated carbonation curing period of 24 h under controlled conditions. The devised mortars were evaluated through mass, dimension, pH measurements, and compressive strength tests. Furthermore, TG-DTG, SEM, FT-IR, XRD, and MIP analyses were performed to investigate the microstructure of the materials developed in this study. Therefore, the devised mortars reached compressive strength results from 9.9 to 24.5 MPa. The TG-DTG, FT-IR, SEM, and XRD analyses support the formation of HMCs in all mixture designs being their volume carbonated in different degrees. Finally, the use of fine particles of biomass bottom ash collaborated for compressive strength enhancement and higher CO2 uptake degree while larger particles do not.

Monitoring Shoreline and Land Use/Land Cover Changes in Sandbanks Provincial Park Using Remote Sensing and Climate Data

Climate change-driven forces and anthropogenic interventions have led to considerable changes in coastal zones and shoreline positions, resulting in coastal erosion or sedimentation. Shoreline change detection through cost-effective methods and easy-access data plays a key role in coastal management, where other effective parameters such as land-use/land-cover (LULC) change should be considered. This paper presents a remotely sensed shoreline monitoring in Sandbanks Provincial Park, Ontario, Canada, from 1984 to 2021. The CoastSat toolkit for Python and a multilayer perceptron (MLP) neural network classifier were used for shoreline detection, and an unsupervised change detection framework followed by a postclassification change detection method was implemented for LULC classification and change detection. The study assessed the recent coastal erosion and accretion trends in the region in association with spatiotemporal changes in the total area of the West and East Lakes, the transition between LULC classes, extreme climate events, population growth, and future climate projection scenarios. The results of the study illustrate that the accretion trend apparently can be seen in most parts of the study area since 1984 and is affected by several factors, including lake water-level changes, total annual precipitations, sand movements, and other hydrologic/climatic parameters. Furthermore, the observed LULC changes could be in line with climate change-driven forces and population growth to accelerate the detected accretion trend in the East and West Lakes. In total, the synergistic interaction of the investigated parameters would result in a greater accretion trend along with a lower groundwater table amid even a low carbon scenario. The discussed findings could be beneficial to regional/provincial authorities, policymakers, and environmental advocates for the sustainable development of coastal communities.

STUDY ON PERVIOUS CONCRETE PAVING BLOCK CONTAINING PLASTIC WASTE TYPE PET AS A SAND REPLACEMENT

This study reports the effects of using plastic waste type PET (Polyethylene Terephthalate) as sand replacement in the manufacture of pervious concrete paving block to be applied for low-traffic volume roads, parking areas and pedestrian walkways. The PET plastic aggregates were prepared through the pre-heated method under 150-180°C and then crushed into pieces to partially replace the sand content in concrete paving block mixtures at percentage of 5%, 10%, 20% and 30% by wt. of total sand. The experimental studies were conducted on concrete paving block (size 210x110x60 mm3) containing PET plastic waste aggregate. The coarse aggregate to cement ratio used was 4:1 while the fine aggregate to cement ratio was 1.5:1. The properties of concrete paving block specimens were evaluated based on the compressive strength, flexural strength, and void ratio results after curing. From the results obtained, it can be concluded that the maximum of percentage when using plastic waste type PET was 5% by wt. of sand. The mechanical properties and void ratio of the concrete paving block showed that the utilization of plastic waste type PET as construction material has potential contribution in improving the pavement structure and offering sustainable solution on environmental issue.