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Peat is a highly soft soil that possesses low shear strength due to the presence of organic content and a high amount of moisture content. In the present study, the peat is stabilized to enhance the strength with fly ash with different percentages of 3, 6, 9, 12, and 15% and reinforced with nylon fiber with 0.5, 1.0 and 1.5% to investigate the performance of peat. The strength of fly ash and fiber-treated peat is compared with cement-treated peat. The Compaction, California bearing ratio (CBR), Unconfined compressive strength (UCS) and Unconsolidated Undrained Triaxial (UU Triaxial), Freezing & Thawing (F&T) tests were used for evaluating the strength properties of peat. The UCS value increases to 280 kPa from 60 kPa at 12% of fly ash content, but at 15% cement content it was increased up to 370 kPa. The UCS value of peat stabilized with 12% of fly ash and reinforced with 1% of fiber obtained as 360 kPa. The CBR also increased to 9.3 from 2.5% for stabilized peat (12% fly ash) and reinforced fiber (1%) in soaked condition whereas the CBR value increases up to 9.7% for the case of 15% cement content. It is observed from the freezing and thawing tests, the strength of fly ash stabilized peat-reinforced fiber is decreased by 50%. Whereas the cement-stabilized peat is reducing its strength by 30%. Therefore, 15% of cement can be replaced with 12% of fly ash and 1% of nylon fiber together to make the stabilization effective in normal conditions, but not durable for weathering actions compared to cement-treated peat. The pavement thickness is evaluated from CBR value and observed that the stabilized peat-reinforced fiber significantly affects the thickness of the pavement. [ABSTRACT FROM AUTHOR]

After a wildfire event, ash is a newly formed surficial soil layer with microscale properties such as roughness, morphology, and chemical composition that may impact how ashes form fabrics in situ and so affect the overall hydrological conditions of a burned area (infiltration capacity, permeability, etc.). To examine the effects of ash microscale properties on macroscale behavior, eight wildfire ash samples from California were characterized physically (specific gravity, specific surface area, particle size, etc.), chemically (elemental composition, organic and inorganic carbon content, etc.), and geotechnically (strength, compaction, saturated hydraulic conductivity, etc.). The tested ashes were found to contain predominantly organic unburned carbons and carbonates derived from the combustion of calcium-oxalate rich fuels in temperatures likely ranging from 300°C to 500°C. Ashes had high specific surface areas because morphologically, particles had highly texturized and porous surfaces. Additional water was necessary to coat the particle surfaces, which led to high liquid limits and compaction optimum moisture contents. Hydraulic conductivity values were within range for silty sands (10−5–10−3 cm/s), and specimens had friction angles near 30°. However, tested ashes consistently demonstrated high void ratios and low bulk densities during testing for strength, hydraulic conductivity, and compaction. These anomalies were attributed to unusual carbonate morphologies; the high interparticle friction of these phases allowed ashes to form looser fabrics than a typical silty sand and contributed to the measured high void ratios, low maximum dry unit weights, and high friction angles. Overall, we hypothesize that the relative amounts of inorganic versus organic constituents in our wildfire ash samples affected how the ashes formed fabrics and so affected their geotechnical properties. Practical Applications: The role of wildfire ash in the postfire hydrological response of a catchment is not perfectly understood. Ash is a very heterogenous material whose properties are directly related to its formation environment (fuel type and accessibility, fire duration, and fire temperature, to name a few). This newly formed surface soil layer has unusual properties compared to natural soils, including low bulk densities and high porosities (sometimes up to 70% or more) in situ, but there is currently not enough information on ash properties in the literature to fully explain why. This study addresses this gap by providing physical, chemical, and geotechnical information about wildfire ashes. This is one of the first studies to specifically test wildfire ash maximum density, Atterberg limits, and shear strength. It provides geotechnical data to the community as well as information about ash chemical and physical properties. We hope that this study not only supplements the current literature on postwildfire landscapes but also informs researchers, engineers, and policy makers about how the formation environment of ash can influence its engineering behavior, such as strength, compressibility, and permeability. [ABSTRACT FROM AUTHOR]

Phosphogypsum, which contains toxic components (e.g., heavy metal elements and fluoride), is one of the byproducts of phosphoric acid production, and filling subgrade is one of the recycling methods for it. In this study, phosphogypsum was stabilized by lime to improve the mechanical properties [California bearing ratio (CBR), resilience modulus, unconfined compressive strength, and shear strength], water stability, and harmful substances dissolubility. Combined with scanning electron microscopy, the strength formation and water stability enhancement mechanism of lime-stabilized phosphogypsum (LSP) were explored. The results demonstrated that the mechanical properties of LSP were better with the lime content of 6%–10%. The CBR, resilience modulus, unconfined compressive strength, and shear strength were 3.35 times, 2.46 times, 8.61 times, and 1.39 times that of plain phosphogypsum, respectively. An intensity prediction model with a correlation of 97% was constructed. The CBR and resilience modulus softening coefficient of LSP reached best values when lime content was 6%–8%. The leaching concentration of arsenic, chromium, and lead of LSP with 2% lime met the quality standards of groundwater levels I, II, and IV, respectively. Fluoride and phosphate were not detected in LSP when lime content was greater than 6.0%. The results show that LSP is feasible as subgrade filler. Considering the mechanical properties, water stability, and dissolution of hazardous substances of LSP, it is recommended to add 6%–8% lime content to LSP as highway subgrade filler. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of using xanthan gum (XG), sodium alginate (SA) and gelatin (G) to stabilise collapsible soil. Modified Proctor, one-dimensional collapse, unconsolidated-undrained triaxial and California bearing ratio (CBR) tests were conducted to estimate the engineering characteristics of the untreated and treated soil. Additionally, x-ray diffraction (XRD) and scanning electron microscopy (SEM) tests were utilised to demonstrate the changes in the microstructure of the treated samples. It was found that biopolymers decreased the maximum dry density and increased the optimum water content. The results also indicated that a 4% content of XG, SA and G significantly reduced the collapse index by 96, 95 and 82%, respectively. Shear tests showed that biopolymers slightly reduced the internal friction angle and significantly increased the cohesion intercept, which led to shear strength improvement. The results also indicated that 4% XG-treated, 4% SA-treated and 4% G-treated samples exhibited higher shear strengths by 145, 106 and 73%, respectively, than the untreated samples under the same conditions. The findings also indicated that when the soil was mixed with a 4% concentration of XG, SA and G, the unsoaked CBR value increased by about 185, 157 and 141%, respectively. [ABSTRACT FROM AUTHOR]

Herein a novel nanocomposite, Praseodymium oxide-nano montmorillonite (Pr-nMMT)was fabricated and explored as stabilising admixture for enhancing the strength of dredged soils. The compaction, permeability, direct shear, california bearing ratio (CBR), and unconfined compressive strength (UCS) tests performed on the dredged soil samples collected from the Shalimar site along the Dal Lake Srinagar rendered it unsuitable as construction material and needed stabilisation before using it as a building material. Different percentages of Pr-nMMT (0.25–1%) were used for stabilisation purposes and it revealed that the addition of Pr-nMMT to soil increased maximum dry density (MDD), shear strength parameters (angle of internal friction and cohesion), CBR, and decreased optimum moisture content (OMC), plasticity index, and hydraulic conductivity. The UCS enhanced notably with Pr-nMMT content and increment in curing time. The optimum Pr-nMMT content determined was 0.5% as it demonstrated the maximum value of UCS at 0, 7 and 14 days of curing beyond which the strength showed a declining trend. It was anticipated that Pr-nMMT filled pores between soil particles, therefore resisting sliding among soil particles and thus increasing the strength of treated dredged soil. The results portray Pr-nMMT as an efficient nano admixture for the stabilisation of dredged soil. [ABSTRACT FROM AUTHOR]

The objective of this paper is to propose a compaction control method that facilitates the use of expansive soil, as embankment material for highways in humid climates. Three types of expansive soils, utilised as general embankment fill in Southern China, were selected for investigating the physical, compaction, and shear strength properties. The compaction-control method was proposed based on the compaction curve revealed by the dry preparation method, associated with the corresponding soaked California bearing ratio. The site test and long-term monitoring were conducted in an embankment in Ningming, which was filled with compacted expansive soil controlled by the suggested method. The laboratory test results showed that the maximum dry unit weight obtained from the dry preparation method was less than that generated from the moist preparation method, while the optimum moisture content acquired from the dry preparation method was greater and closer to its natural moisture content. The moisture content corresponding to maximum CBR was 2% larger than the optimum moisture content. The in-situ monitoring results presented that the moisture content of the constructed embankment was close to its natural moisture content or plastic limit, the maximum settlement was 70.6 mm, and the maximum horizontal displacement was 20 mm. [ABSTRACT FROM AUTHOR]

Pozzolanic reactions of rice husk ash (RHA) entirely depend on controlled burning condition. The current study illustrates the effects of controlled burn RHA on the geotechnical properties of A-2-4 soil as per the American Association of State Highway and Transportations Officials (AASHTO) classification. The compactibility, bearing capacity, compressive strength, shear strength, and scanning electron micrographs were investigated as the important geotechnical properties of soil with 0%, 5%, 10%, and 15% of RHA admixtures considering the 7-day moist curing. The test results showed that the optimum moisture content increased, but maximum dry density reduced with the increment of RHA content. Soil with 5% RHA showed the increased percentage of California bearing ratio (39.5%), unconfined compressive strength (6.0%), modulus of deformation (56.3%), cohesion (11.8%), and angle of internal friction (6.3%) compared to untreated soil specimen which indicated that the application of burnt RHA at a controlled temperature enhanced the geotechnical properties of soil. Scanning electron microscopy image on soil with 5% RHA also observed the best microstructural development, which recommends that soil with 5% RHA can be used as a construction material for rural roads and pedestrian roads. [ABSTRACT FROM AUTHOR]

Steel slag accumulation is one of the major issues for steel manufacturing companies, because it occupies a large portion of a company's yard. Investigators have suggested various applications for using slag in other industries. There is great potential for using slag as an aggregate in road and railway construction. Evidence demonstrates the compatibility of slag for road base and subbase construction. However, the use of slag as a subballast for railway construction has not been investigated thoroughly. This research studied the application of slag to subballast railway construction. A railway subballast layer requires a high shear strength, which is greater than slag's shear strength. Therefore, the authors modified the slag with 1%, 2%, and 3% gilsonite, or natural binder, and performed Los Angeles abrasion, direct shear, and California bearing ratio tests on the modified slag. The results of all experiments indicated significant improvement in the modified slag's shear strength properties, which makes gilsonite-modified slag a potential replacement for traditional subballast material. [ABSTRACT FROM AUTHOR]

Pavements constructed over poor subgrade soil will lead to rapid increase in construction and maintenance costs due to increase in crust thickness and frequent failure. In a developing country, like India, costs play a very significant role. In India, more than 20% of the land area is covered with soils having low California bearing ratio (CBR) and shear strength values. These soils consist of a substantial amount of fines; i.e., a high percent of silt and clay, losing significantly in strength upon coming in contact with water. This paper presents the effect of geogrid reinforcement on the strength behaviour of poor subgrade soil. The geogrids are placed in single and double layers from the top of mold and heavy compaction and soaked CBR tests are performed. It is observed that geogrid reinforcement increases the CBR value significantly, thus causing significant reductions in pavement thickness and cost. Multiple linear regression models were developed for predicting soaked CBR. [ABSTRACT FROM AUTHOR]

Microbially induced calcium carbonate precipitation (MICP) technology has a great potential for improving the engineering properties of recycled aggregates, but the major limitation is the inhomogeneous distribution of calcium carbonate precipitation resulting in the nonuniform modification of recycled aggregates. This paper proposed a spraying method to equally distribute the calcium carbonate, and discussed the influence of the new treatment on the physical and mechanical properties of the MICP modified recycled aggregates. The results showed that the water absorption of the coarse, medium and fine aggregates after seven cycles of treatment was greatly reduced by 58%, 26% and 46%, respectively. The shear strength, crushing value and California bearing ratio (CBR) were increased by the treatments, while the improvement was limited by the strength of the generated calcium carbonate precipitation. A significant decrease in the porosity and total pore volume was found after treatments, and the cubic and spherical calcium carbonate crystals were generated on the surface of the recycled aggregates. This indicated that the improvement of the physical and mechanical properties of the recycled aggregates was mainly attributed to the generated calcium carbonate filling the pores and reinforcing the surface. The MICP technology facilitates the high-value utilization of the recycled aggregates in pavement engineering. [ABSTRACT FROM AUTHOR]

This investigation was conducted to evaluate the influence of waste placement practices on the engineering response of municipal solid waste (MSW) landfills. Waste placement conditions were varied by moisture addition to the wastes at the time of disposal. Tests were conducted at a California landfill in test plots (residential component of incoming wastes) and full-scale active face (all incoming wastes including residential, commercial, and self-delivered components). The short-term effects of moisture addition were assessed by investigating compaction characteristics and moisture distribution and the long-term effects by estimating settlement characteristics of the variably placed wastes. In addition, effects on engineering properties including hydraulic conductivity and shear strength, as well as economic aspects were investigated. The unit weight of the wastes increased with moisture addition to a maximum value and then decreased with further moisture addition. At the optimum moisture conditions, 68% more waste could be placed in the same landfill volume compared to the baseline conditions. Moisture addition raised the volumetric moisture content of the wastes to the range 33–42%, consistent with values at and above field capacity. Moisture transfer occurred between consecutive layers of compacted wastes and a moisture addition schedule of 2 days of as-received conditions and 1 day of moisture addition was recommended. Settlement of wastes was estimated to increase with moisture addition, with a 34% increase at optimum moisture compared to as-received conditions. Overall, moisture addition during compaction increased unit weight, the amount of incoming wastes disposed in a given landfill volume, biological activity potential, and predicted settlement. The combined effects have significant environmental and economic implications for landfill operations. [ABSTRACT FROM AUTHOR]

Soil in embankments is often amended with several additives for supporting the vegetation growth on the side slopes. Biochar, a stable, nutrient loaded and moisture retentive material, could be amended to the embankment soils. The positive impacts of biochar on soil properties, soil water and nutrient retention, microbial activity and growth of crops are well established. However, the load-bearing capacity of biochar-amended soil which is utmost important for a material to be used in embankment is rarely reported in literature. The present study aims to investigate the shear strength and load-bearing capacity of biochar-amended soil for application in embankments. For assessing the shear strength and load-bearing capacity, California bearing ratio (CBR) and direct shear tests were conducted on bare and 5%, 10% and 15% (w /w) biochar-amended silty sand and pure sand. The results revealed that the biochar amendment decreased the dry unit weight (6–19%), and increased the shear strength (cohesion (c) and angle of internal friction (ϕ)) and load-bearing capacity of both the soils by 22–228% and 17–89% respectively. Further, the biochar amendment improved the vegetation root (34–108%) and shoot (29–157%) mass, ensuring the enhanced stability and protection (erosion). Thus, the results suggest the application of biochar-amended soil in embankments, however future field-scale trials are needed before application. [ABSTRACT FROM AUTHOR]

• The incorporation of RA can reduce the OMC and MDD of high liquid limit clay. • The UCS and the cohesion of the treated clay peaks at the RA content of 15%. • The increase of concrete-to-brick ratio can increase the UCS and the internal angle of the treated clay. • The increasing RA content and concrete-to-brick ratio result in larger CBR values and better immersion stability. • Recycled aggregate can promote the formation of agglomerates and increase stability. High liquid limit soil has low strength and poor immersion stability, which may cause engineering problems when used as embankment filling. In this paper, recycled concrete aggregate (RCA) and recycled brick aggregate (RCB) were used to improve the mechanical strength and immersion stability of high liquid limit clay. A series of laboratory tests including compaction tests, unconfined compression strength (UCS) test, direct shear test, California bearing ratio (CBR) test and Scanning electron microscope (SEM) test was carried out to study the evolution of mechanical properties of treated soil. The test results show that the addition of recycled aggregate (RA) would reduce the optimum water content (OWC) and maximum dry density (MDD) of high liquid limit clay. With the increase of the content of RA, the UCS of the treated soil generally increases first and then decreases. The longer the curing age, the greater the UCS. Mixing RA with high liquid limit clay will increase the stability and shear strength of high liquid limit clay. With the increase of RA content, the internal friction angle of the treated soil gradually increases; the cohesion first increases and then decreases. Compared with the untreated high liquid limit clay, the bearing capacity and immersion stability of the treated soil have been significantly treated, and with higher content of RCA, the bearing capacity and immersion stability of the treated soil trend to be stronger. SEM images show that the incorporation of RA can promote the formation of agglomerates to increase the integrity. The results of this experimental study can provide reference value for actual engineering. [ABSTRACT FROM AUTHOR]

Strength properties of compacted ash layers depend to a great extent on the moulding conditions. This paper focuses on the effects of compaction energy and degree of saturation on strength characteristics of compacted pond ash. The pond ash sample, collected from the ash pond of Rourkela Steel Plant (RSP), was subjected to compactive energies varying from 357 kJ/m3to 3488 kJ/m3. The optimum moisture content and maximum dry densities corresponding to different compactive energies were determined by conventional compaction tests. The shear strength parameters, unconfined compressive strengths (UCS) and California bearing ratio (CBR) values of specimens compacted to different dry densities and moisture content were assessed and reported. The effects of compaction energy and degree of saturation on shear strength parameters i.e. unit cohesion (cu) and angle of internal friction (Ф) values and also the UCS values are evaluated and presented herein. The results indicate that the dry density and strength of the compacted pond ash can be suitably modified by controlling the compactive energy and moulding moisture content. The strength achieved in the present study is comparable to the good quality, similar graded conventional earth materials. Hence, it may be safely concluded that pond ash can replace the natural earth materials in geotechnical constructions. [ABSTRACT FROM AUTHOR]

Abstract: Regional seismic landslide hazard maps are based on predictions of rigid-sliding-block displacement derived from estimates of earthquake ground shaking, topography, geology, and shear strength. The confidence in these predictions requires comparisons with field observations of landslide occurrence during previous well-documented earthquakes. This paper presents a comparison between observed landslides from the 1994 Northridge, California earthquake and predicted landslides based on sliding-block displacement estimates. Seven empirical displacement models, each of which uses a different combination of ground-motion parameters, are investigated to evaluate which models and associated ground-motion parameters best predict seismic landslides. Using best estimates of ground shaking and shear-strength properties from the Northridge earthquake, sliding displacements are calculated and compared with the locations of observed landslides. Only 20–40% of the observed landslides are captured and the total area of predicted landslides is much larger than observed. The ability to predict landslide occurrence accurately depends less on the displacement model and associated ground-motion parameters, and more on the uncertainty in the model parameters, particularly the assigned shear-strengths. Because current approaches do not take into account the spatial variability of shear strength within individual geologic units, the accuracy of the predictive models is controlled predominantly by the distribution of slope angles within a geologic unit. Assigning overly conservative (low) shear-strength values results in a higher percentage of landslides accurately identified but also results in a large over-estimation of the total landslide area. Making more accurate maps of seismic landslide hazards will require methods to define intra-formational variations in shear strength. [Copyright &y& Elsevier]

Machine-learning has recently gained considerable attention in the earthquake engineering community, as it can map the complex relationship between the expected damage and the input parameters. It is often necessary to understand the reasons for the behavior and predictions of the machine-learning model. This paper addresses this issue through interpretable machine-learning approaches such as partial dependence plots, accumulated local effects, and Shapely additive explanations. The evaluation of these approaches is carried out (1) at a component level by analyzing the shear strength predictions by a machine-learning model and (2) at a regional level through the machine-learning model for the regional damage assessment of bridges in California. The comparison helps to identify (1) the proper implementation of these approaches for the efficient use of machine-learning models and (2) key influential variables and thresholds that govern the prediction of the machine-learning models. [ABSTRACT FROM AUTHOR]

A comprehensive large-scale laboratory testing program using direct shear (DS), triaxial (TX), and simple shear tests was performed on municipal solid waste (MSW) retrieved from a landfill in the San Francisco Bay area to develop insights about and a framework for interpretation of the shear strength of MSW. Stability analyses of MSW landfills require characterization of the shear strength of MSW. Although MSW is variable and a difficult material to test, its shear strength can be evaluated rationally to develop reasonable estimates. The effects of waste composition, fibrous particle orientation, confining stress, rate of loading, stress path, stress-strain compatibility, and unit weight on the shear strength of MSW were evaluated in the testing program described herein. The results of this testing program indicate that the DS test is appropriate to evaluate the shear strength of MSW along its weakest orientation (i.e., on a plane parallel to the preferred orientation of the larger fibrous particles within MSW). These laboratory results and the results of more than 100 large-scale laboratory tests from other studies indicate that the DS static shear strength of MSW is best characterized by a cohesion of 15 kPa and a friction angle of 36° at normal stress of 1 atm with the friction angle decreasing by 5° for every log cycle increase in normal stress. Other shearing modes that engage the fibrous materials within MSW (e.g., TX) produce higher friction angles. The dynamic shear strength of MSW can be estimated conservatively to be 20% greater than its static strength. These recommendations are based on tests of MSW with a moisture content below its field capacity; therefore, cyclic degradation due to pore pressure generation has not been considered in its development. [ABSTRACT FROM AUTHOR]

The application of construction waste as an aggregate in subgrade backfilling is an important recycling option. This study analyzed a subgrade backfill material consisting of lime-fly ash construction waste mixture (LFCWM). Compaction and California bearing ratio (CBR) tests were performed on LFCWM under different cement-aggregate ratios (CARs, 3:7, 4:6, 5:5, 8:2). Different normal stresses (100, 200, and 300 kPa) and aggregate sizes (20%, 40%, 60%, 80% of P4.75) were also evaluated. The experimental results indicated that: (1) when the CAR was 4:6, the optimum water content and the maximum dry density reached their maximum values of 10.1% and 2.03 g/cm3, respectively, the maximum CBR value was 42.5%, and the shear strength reached its maximum value. (2) With an increase in shear displacement, the shear stress showed a rapid initial increase, then a slow decrease, and finally tended to stabilize. (3) Normal stress had a positive effect on the shear strength of the mixture. (4) When P4.75 was 40%, the shear strength of LFCWM was the maximum. The research results have been successfully applied to road engineering, providing an important reference for the application of construction waste aggregate in roadbed engineering. [ABSTRACT FROM AUTHOR]

• The role of the compaction effort on geotechnical behavior of waste foundry sands was investigated. • Increasing of compaction effort causes remarkable changes in terms of bearing capacity and shear strength. • Suction plays a remarkable role in the behavior of waste foundry sand after being air-dried. • Waste foundry sand requires a rigorous compaction control. Brazil produces more than 3 million tons of waste foundry sands (WFS) each year. Although this material presents characteristics that fulfill the environmental requirements to be recycled and used as a building material, the lack of information regarding its geotechnical behavior inhibits its use, mainly in applications that require good performance. Therefore, this study investigates the role of the compaction effort on the behavior of compacted WFS considering its application as a building material in geotechnical work. The experimental procedures include X-ray fluorescence analysis, scanning electron microscopy, determination of compaction curves, California bearing ratio (CBR), the execution of unconfined compression, direct shear, and oedometric tests. Geomechanical tests were conducted on specimens compacted with three distinct compaction efforts: 600 kJ/m3, 1260 kJ/m3 and 2700 kJ/m3. The WFS is composed mainly of quartz particles with subangular to subrounded shape. Fines are 12% of its composition, and WFS is classified as a well-graded material. Optimum moisture content ranges between 9.0 and 11.5%. The higher the compaction effort, the lower is the void ratio. Despite the differences in the void ratios are small, they affect the CBR values dramatically. Compaction effort increases friction angle and unconfined compressive strength and reduces compressibility. Suction plays a remarkable role in the behavior of such material after being air-dried. This study can contribute to a better understanding of potentialities and limitations for the use of WFS in compacted conditions. [ABSTRACT FROM AUTHOR]

• Bearing capacity and physical properties of waste foundry sand were studied. • Shear strength properties of waste foundry sand were investigated using direct shear and triaxial testing. • Stress-dilatancy behaviour of waste foundry sand was investigated. • Comparison was made with recycled glass as an established recycled material. • Waste foundry sand was found suitable as an engineered fill and road embankment fill material. This research evaluates the engineering properties of waste foundry sand (WFS) as a sustainable construction material. In this research study, extensive laboratory experiments, including X-ray fluorescence (XRF), pH value, particle size distribution, California bearing ratio (CBR) and consolidated drained (CD) direct shear and CD triaxial tests were conducted. In addition, for the comparison purpose, a similar testing program was applied to a control material, namely sand sized waste recycled glass (RG), which is an accepted construction material for geotechnical and pavement construction projects. Results indicated that although the strength properties of WFS were lower than those of RG, the WFS could meet the required characteristics to be used in applications such as engineering fill and road embankments. The outcomes of this research aim to increase the market demand for WFS as a solid waste by improving the construction industry's confidence in its performance. Using WFS as an alternative to natural sands in the construction activities can potentially have significant positive environmental impacts through reducing CO 2 emission, as well as preventing the expansion of landfills for the disposal of WFS. [ABSTRACT FROM AUTHOR]