scholarly journals Numerical analysis of reinforced embankment slopes made up of pozzolanic waste materials

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Vidya N. Patil ◽  
Hemant S. Chore ◽  
Vishwas A. Sawant
Keyword(s):  
Fly Ash ◽  
Bearing Capacity ◽  
Numerical Study ◽  
Slope Angle ◽  
Waste Materials ◽  
Embedment Depth ◽  
Embankment Slope ◽  
Edge Distance ◽  
Critical Slope ◽  
Grid Reinforcement

AbstractThe paper presents the numerical study of the bearing capacity behavior of the model footing placed on the top of reinforced embankment slopes made up of Pozzolanic waste materials such as fly ash and ground granulated blast furnace slag (GGBFS). The present investigation is aimed at studying the efficacy of the different types of reinforcement (geogrid and rubbergrid) in improving the load bearing capacity of the embankment slopes made up of waste materials. The effect of various parameters such as slope angle, location of the footing with slope crest, embedment depth of the reinforcement is studied on the strength behavior of the embankment. The analysis is carried out on unreinforced fly ash and GGBFS embankments for three slope angles and three locations of the footing with respect to slope crest, i.e., edge distance. The fly ash slopes reinforced with geogrid and rubber grid reinforcement is also analyzed for all the three slope angles and edge distances as that in unreinforced fly ash embankment slope and further, for various embedment depths of the layer of reinforcement. The GGBFS embankment reinforced with geogrid layer is analyzed with respect to critical slope angle and edge distance and optimum embedment depth of the reinforcement deduced from the unreinforced fly ash and GGBFS embankment and reinforced fly ash embankment. The analysis demonstrated that the load carrying capacity of the embankment slope decreases with increase in slope angle and edge distance in respect of unreinforced and reinforced fly ash slope and the optimum embedment depth ratio seems to be 1.2. Further, the rubbergrid reinforcement is found to perform better than the geogrid. The performance of geogrid reinforced GGBFS embankment is also noteworthy. The study underscores the effective utilization of Pozzolanic waste materials as the embankment slope and the rubbergrid derived out of discarded tyres.

Experimental and numerical studies of geosynthetic-reinforced sand slopes loaded with a footing

2000 ◽  
Vol 37 (4) ◽  
pp. 828-842 ◽  
Author(s):  
K M Lee ◽  
V R Manjunath
Keyword(s):  
Finite Element ◽  
Bearing Capacity ◽  
Numerical Study ◽  
Slope Angle ◽  
Model Tests ◽  
Axial Stiffness ◽  
Edge Distance ◽  
Optimum Geometry ◽  
Fill Slope ◽  
Settlement Behaviour

This paper presents the results of a series of plane strain model tests carried out on both reinforced and unreinforced sand slopes loaded with a rigid strip footing. The objectives of this study are to (i) determine the influence of geosynthetic reinforcement on the bearing-capacity characteristics of the footing on slope, (ii) understand the failure mechanism of reinforced slopes, and (iii) suggest an optimum geometry of reinforcement placement. The investigations were carried out by varying the edge distance of the footing for three different slope angles and three different types of geosynthetic. It is shown that the load-settlement behaviour and ultimate bearing capacity of the footing can be considerably improved by the inclusion of a reinforcing layer at the appropriate location in the fill slope. The optimum depth of the reinforcement layer, which resulted in maximum bearing capacity ratio (BCR), is found to be 0.5 times the width of the footing. It is also shown that for both reinforced and unreinforced slopes, the bearing capacity decreases with an increase in slope angle and a decrease in edge distance. At an edge distance of five times the width of the footing, bearing capacity becomes independent of the slope angle. The effectiveness of the geosynthetic in improving the bearing capacity of the footing is attributed to its primary properties such as aperture size and axial stiffness. A numerical study using finite element analyses was carried out to verify the model test results. The agreement between observed and computed results is found to be reasonably good in terms of load-settlement behaviour and optimum geometry of georeinforcement placement.Key words: model tests, footing, bearing capacity, fill slope, finite element method, geosynthetic.

scholarly journals Estimating the Uplift Bearing Capacity of Belled Piers Adjacent to Sloping Ground by Numerical Modeling Based on Field Tests

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Yangchun Han ◽  
Jiulong Cheng ◽  
Weifeng Zheng ◽  
Shijun Ding
Keyword(s):  
Numerical Modeling ◽  
Bearing Capacity ◽  
Attenuation Coefficient ◽  
Slope Angle ◽  
Field Tests ◽  
Embedment Depth ◽  
Sloping Ground ◽  
Foundation Model ◽  
The Difference ◽  
The Impact

In order to evaluate the uplift bearing capacity of belled piers beside slopes, a series of numerical simulations are carried out based on field tests data. First, a number of uplift loading tests of full-scale belled piers are carried out on the project site of transmission line in Anhui Province, China. Second, a slope-foundation model for numerical modeling is proposed and calibrated based on field tests data. The behavior of belled piers adjacent to slopes subject to uplift load is studied by numerical modeling. The impact of three parameters, including distance (a) from the belled pier to the crest of the slope, slope angle (β), and embedment depth (h) of the belled pier, has been investigated on the uplift capacity of the belled pier. Based on the simulation results, an attenuation coefficient (ω) is put forward for evaluating the reduction of uplift bearing capacity of the belled pier. The results show that the coefficient ω is negatively correlated with distance a and depth h, and the influence of distance a is greater than that of depth h according to the results of variance analysis, but the difference is not significant by F test. Moreover, the empirical equation between attenuation coefficient ω and three key factors a, β, and h had been presented by a series of fitting.

scholarly journals Pressure Settlement Behaviour and Bearing Capacity of Asymmetric Embedded Plus Shaped Footing on Layered Sand

2021 ◽  
Vol 31 (3) ◽  
pp. 152-176
Author(s):  
Priyanka Rawat ◽  
Rakesh Kumar Dutta
Keyword(s):  
Bearing Capacity ◽  
Numerical Study ◽  
Friction Angle ◽  
Thickness Ratio ◽  
Embedment Depth ◽  
Loose Sand ◽  
Dense Sand ◽  
Comparison Of The Results ◽  
Abaqus Software ◽  
Settlement Behaviour

Abstract The aim of the present numerical study was to analyse the pressure settlement behaviour and bearing capacity of asymmetric plus shaped footing resting on loose sand overlying dense sand at varying embedment depth. The numerical investigation was carried out using ABAQUS software. The effect of depth of embedment, friction angle of upper loose and lower dense sand layer and thickness of upper loose sand on the bearing capacity of the asymmetric plus shaped footing was studied in this investigation. Further, the comparison of the results of the bearing capacity was made between the asymmetric and symmetric plus shaped footing. The results reveal that with increase in depth of embedment, the dimensionless bearing capacity of the footings increased. The highest increase in the dimensionless bearing capacity was observed at embedment ratio of 1.5. The increase in the bearing capacity was 12.62 and 11.40 times with respect to the surface footings F1 and F2 corresponding to a thickness ratio of 1.5. The lowest increase in the dimensionless bearing capacity was observed at embedment ratio of 0.1 and the corresponding increase in the bearing capacity was 1.05 and 1.02 times with respect to the surface footing for footings F1 and F2 at a thickness ratio of 1.5.

scholarly journals Numerical and Experimental Investigation on Concrete Splitting Failure of Anchor Channels

CivilEng ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 502-522
Author(s):  
Anton Bogdanić ◽  
Daniele Casucci ◽  
Joško Ožbolt
Keyword(s):  
Construction Industry ◽  
Failure Mode ◽  
Current Trend ◽  
The United States ◽  
Embedment Depth ◽  
Test Results ◽  
Concrete Members ◽  
Splitting Failure ◽  
Edge Distance ◽  
Numerical Parametric Study

Concrete splitting failure due to tension load can occur when fastening systems are located close to an edge or corner of a concrete member, especially in thin members. This failure mode has not been extensively investigated for anchor channels. Given the current trend in the construction industry towards more slender concrete members, this failure mode will become more and more relevant. In addition, significantly different design rules in the United States and Europe indicate the need for harmonization between codes. Therefore, an extensive numerical parametric study was carried out to evaluate the influence of member thickness, edge distance, and anchor spacing on the capacity of anchor channels in uncracked and unreinforced concrete members. One of the main findings was that the characteristic edge distance depends on the member thickness and can be larger than 3hef (hef = embedment depth) for thin members. Based on the numerical and experimental test results, modifications of the design recommendations for the splitting failure mode are proposed. Overall, the authors recommend performing the splitting verification separately from the concrete breakout to design anchor channels in thin members more accurately.

scholarly journals Neutralization of Acidic Wastewater from a Steel Plant by Using CaO-Containing Waste Materials from Pulp and Paper Industries

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2653
Author(s):  
Tova Jarnerud ◽  
Andrey V. Karasev ◽  
Pär G. Jönsson
Keyword(s):  
Fly Ash ◽  
Pulp And Paper ◽  
Waste Materials ◽  
Paper Mills ◽  
Steel Mills ◽  
Lime Mud ◽  
Set Up ◽  
Pulp And Paper Industries ◽  
The Given ◽  
Acidic Wastewater

In this study, CaO-containing wastes from pulp and paper industries such as fly ash (FA) and calcined lime mud (LM) were utilized to neutralize and purify acidic wastewaters from the pickling processes in steel mills. The investigations were conducted by laboratory scale trials using four different batches of wastewaters and additions of two types of CaO-containing waste materials. Primary lime (PL), which is usually used for the neutralization, was also tested in the same experimental set up in the sake of comparison. The results show that these secondary lime sources can effectively increase the pH of the acidic wastewaters as good as the commonly used primary lime. Therefore, these secondary lime sources could be potential candidates for application in neutralization processes of industrial acidic wastewater treatment. Moreover, concentrations of metals (such as Cr, Fe, Ni, Mo and Zn) can decrease dramatically after neutralization by using secondary lime. The LM has a purification effect from the given metals, similar to the PL. Application of fly ash and calcined lime mud as neutralizing agents can reduce the amount of waste from pulp and paper mills sent to landfill and decrease the need for nature lime materials in the steel industry.

A Numerical Study on the Seismic Site Response of Rocky Valleys with Irregular Topographic Conditions

2019 ◽  
Vol 10 (04) ◽  
pp. 1850011 ◽  
Author(s):  
Mohammad Katebi ◽  
Behrouz Gatmiri ◽  
Pooneh Maghoul
Keyword(s):  
Seismic Analysis ◽  
Numerical Study ◽  
Site Response ◽  
Slope Angle ◽  
Response Spectra ◽  
Topographic Effects ◽  
Combined Effects ◽  
Acceleration Response ◽  
Vertically Propagating ◽  
Maximum Amplification

This paper investigates topographic effects of rocky valleys with irregular topographic conditions subjected to vertically propagating SV waves of Ricker type using a boundary element code. Valleys with two intersecting slopes, [Formula: see text] and [Formula: see text], are modelled in order to study their combined effects on ground motion. Presented in the form of pseudo-acceleration response spectra, results of this work can be extended to similar topographies. The main findings are: (i) [Formula: see text] (the first slope angle) and [Formula: see text] (L is the half width of the valley and [Formula: see text] is its corresponding height) have amplifying effects, and [Formula: see text] (the second slope angle) has de-amplifying effects on the site response. (ii) [Formula: see text] has a straight effect on intensifying the effects of both [Formula: see text] and [Formula: see text]. (iii) The combined effects of slope angles have been found to be important in modifying the response so more than a single slope should be considered for seismic analysis. (iv) Engineers should use the maximum amplification of 2.4 in case of valleys with the first and second slope angles below [Formula: see text].

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