scholarly journals Performance of soft clay stabilized with sand columns treated by silica fume

2018 ◽  
Vol 162 ◽  
pp. 01007
Author(s):  
Zeena Samueel ◽  
Hussein Karim ◽  
Mohammed Mohammed
Keyword(s):  
Silica Fume ◽  
Carrying Capacity ◽  
Construction Projects ◽  
Ground Improvement ◽  
Soft Clay ◽  
Road Construction ◽  
Reduction Ratio ◽  
Area Replacement Ratio ◽  
Second Category ◽  
Improvement Ratio

In many road construction projects, if weak soil exists, then uncontrollable settlement and critical load carrying capacity are major difficult problems to the safety and serviceability of roads in these areas. Thus ground improvement is essential to achieve the required level of performance. The paper presents results of the tests of four categories. First category was performed on saturated soft bed of clay without any treatment, the second category shed light on the improvement achieved in loading carrying capacity and settlement as a result of reinforcing with conventional sand columns at area replacement ratio = 0.196. The third set investigates the bed reinforced by sand columns stabilized with dry silica fume at different percentages (3, 5 and 7%) and the fourth set investigates the behavior of sand columns treated with slurry silica fume at two percentages (10 and 12%). All sand columns models were constructed at (R.D= 60%). Model tests were performed on bed of saturated soil prepared at undrained shear strength between 16-20 kPa for all models. For all cases, the model test was loaded gradually by stress increments up to failure. Stress deformation measurements are recorded and analyzed in terms of bearing improvement ratio and settlement reduction ratio. Optimum results were indicated from soil treated with sand columns stabilized with 7% dry silica fume at medium state reflecting the highest bearing improvement ratio (3.04) and the settlement reduction ratio (0.09) after 7 days curing. While soil treated with sand columns stabilized with 10% slurry silica fume provided higher bearing improvement ratio 3.13 with lower settlement reduction ratio of 0.57 after 7-days curing.

scholarly journals Settlement Behaviour of Soft Clay Bed Reinforced with Stone Column under Sustained Loading

2019 ◽  
Vol 9 (2) ◽  
pp. 1744-1749
Keyword(s):  
Ground Improvement ◽  
Soft Soil ◽  
Soft Clay ◽  
Reinforced Soil ◽  
Sustained Load ◽  
Stone Column ◽  
Sustained Loading ◽  
Settlement Behavior ◽  
High Area ◽  
Area Replacement Ratio

This research paper investigates the behaviour of soft clay reinforced with stone column under sustained loading. Experiments were conducted in the laboratory on stone column reinforced prepared soft soil bed of kaolin having strength of 7.5 kPa with aggregate of size 2.5 to 10 mm as column material. The stone column with four diameters of 38.1, 50.8, 63.5 and 76.2mm were constructed which correspond to low to high area replacements ratios (i.e. 6.93% - 26.49%). The plain and reinforced soft clay beds were subjected to a sustained load of 150, 200, 250 and 300 kPa where each applied load has been maintained for 24 hours and the settlement behavior of composite ground was taken into account. The test results represent the settlement of reinforced soil bed decreases with increase of column diameters. The settlement reduction ratio is a measure of ground improvement which increases with area replacement ratio. The experimental and theoretical results values were compared as per IS15284 (Part 1): 2003 with reference of stress concentration ratio ‘n’(The ratio of stress in the column to the stress of surrounding ground area). The % variation in theoretical and experimental results is in the range of 50% and therefore the theoretical procedure needs to be revised.

Uplift and Settlement Prediction Model of Marine Clay Soil e Integrated with Polyurethane Foam

2019 ◽  
Vol 9 (1) ◽  
pp. 481-489
Author(s):  
D.C. Lat ◽  
I.B.M. Jais ◽  
N. Ali ◽  
B. Baharom ◽  
N.Z. Mohd Yunus ◽  
...  
Keyword(s):  
Polyurethane Foam ◽  
Clay Soil ◽  
Ground Improvement ◽  
Soft Soil ◽  
Soft Clay ◽  
Effective Thickness ◽  
Marine Clay ◽  
Uplift Pressure ◽  
Pu Foam ◽  
Improvement Method

AbstractPolyurethane (PU) foam is a lightweight material that can be used efficiently as a ground improvement method in solving excessive and differential settlement of soil foundation mainly for infrastructures such as road, highway and parking spaces. The ground improvement method is done by excavation and removal of soft soil at shallow depth and replacement with lightweight PU foam slab. This study is done to simulate the model of marine clay soil integrated with polyurethane foam using finite element method (FEM) PLAXIS 2D for prediction of settlement behavior and uplift effect due to polyurethane foam mitigation method. Model of soft clay foundation stabilized with PU foam slab with variation in thickness and overburden loads were analyzed. Results from FEM exhibited the same trend as the results of the analytical method whereby PU foam has successfully reduced the amount of settlement significantly. With the increase in PU foam thickness, the settlement is reduced, nonetheless the uplift pressure starts to increase beyond the line of effective thickness. PU foam design chart has been produced for practical application in order to adopt the effective thickness of PU foam within tolerable settlement value and uplift pressure with respect to different overburden loads for ground improvement works.

scholarly journals Identification of geodetic risk factors occurring at the construction project preparation stage

2019 ◽  
Vol 9 (1) ◽  
pp. 14-17 ◽  
Author(s):  
Magdalena Kowacka ◽  
Dariusz Skorupka ◽  
Artur Duchaczek ◽  
Paweł Zagrodnik
Keyword(s):  
Risk Factors ◽  
Construction Projects ◽  
Expert Knowledge ◽  
Construction Project ◽  
Road Construction ◽  
Construction Process ◽  
The Road ◽  
Initial Stage ◽  
Preparation Stage

AbstractThe work contains information on the implementation of surveying works in the road construction process. The aim of the research was to identify geodetic risk factors occurring at the stage of preparation of a construction project, the presence of which can greatly disrupt the undertaking such as the road construction. The research was carried out on the basis of expert knowledge, documentation obtained from various road construction projects and the analysis of disturbances at the initial stage of works.

scholarly journals Earthwork Planning and Visualisation of Time-Location Information in Road Construction Projects

2016 ◽  
Vol 1 ◽  
pp. 75
Author(s):  
R. K. Shah
Keyword(s):  
Construction Projects ◽  
Progress Monitoring ◽  
Road Construction ◽  
Resource Planning ◽  
Automatic Generation ◽  
Prototype Model ◽  
Accurate Information ◽  
Planning And Scheduling ◽  
Time Space ◽  
College Of Engineering

<p>Accurate information of locations from visual aspect is vital for efficient resource planning and managing the workspace conflicts in the earthwork operations, which are missing in the existing linear schedules. Hence, the construction managers have to depend on the subjective decisions and intangible imagining for resources allocation, workspace conflicts and location-based progress monitoring in the earthwork projects. This has caused uncertainties in planning and scheduling of earthworks, and consequently delays and cost overruns of the projects. To overcome these issues, a framework of computer based prototype model was developed using the theory of location-based planning. This paper focuses on the case study experiments to demonstrate the functions of the model, which includes automatic generation of location-based earthwork schedules and visualisation of cut-fill locations on a weekly basis. The experiment results confirmed the model’s capability in identifying precise weekly locations of cut-fill and also visualising the time-space conflicts at the earthwork projects. Hence, the paper concludes that the model is a useful decision supporting tool to improve site productivity and reduce production cost of earthworks in the construction projects like roads and railways. </p><p><em>Journal of Advanced College of Engineering and Management, Vol. 1, 2015</em>, pp. 75-84</p>

scholarly journals Delay and cost overrun in road construction projects in Jordan

2015 ◽  
Vol 4 (2) ◽  
pp. 288 ◽  
Author(s):  
Nabil Al-Hazim ◽  
Zaydoun Abusalem
Keyword(s):  
Construction Projects ◽  
Road Construction ◽  
Weather Conditions ◽  
Public Works ◽  
Fiscal Year ◽  
Cost Overrun ◽  
Construction Time ◽  
Change Orders ◽  
Critical Problems ◽  
The Cost

This study aims to identify the most important factors that cause delay in road construction projects in Jordan, which results in cost and time overrun allocated for this type of engineering projects and cause critical problems for both the developer and the contractor. The gap between the cost at completion and that originally estimated, known as cost overrun, can be regarded as one of the most important parameters reflecting the success of projects. In the public sector, money spent on project change orders results in increased construction time which in return reduces the number and size of the projects that can be completed during any given fiscal year. To achieve this goal, the documents and the final reports for several sample projects implemented over the years 2000 to 2008 were analyzed. All the projects were administered by the same organization taken from Jordan Ministry of Rural and Public Works. The results of this study can assist highway officials in their design, planning, scheduling and projects completions so that necessary actions can be taken to control these overruns in future projects. The study showed that 19 factors might cause delays of road construction projects as defined through a detailed literature review. The analysis of the study indicated that the top causes affecting time and cost overrun in road construction projects in Jordan are Terrain and Weather conditions.

scholarly journals Risk of Snake Entanglement Is Affected by Installation Method of Erosion Control Blankets

2020 ◽  
Vol 11 (1) ◽  
pp. 273-278 ◽  
Author(s):  
Krista J. Ward ◽  
Kasey L. Jobe ◽  
Nicholas C. Schiwitz ◽  
Daniel Saenz ◽  
Christopher M. Schalk
Keyword(s):  
Soil Loss ◽  
Construction Projects ◽  
Road Construction ◽  
Erosion Control ◽  
Decision Makers ◽  
Experimental Setting ◽  
Control Product ◽  
Promote Plant Growth ◽  
Edge Treatment ◽  
Pass Through

Abstract At the conclusion of road construction projects, an erosion control product (e.g., blankets, spray mulch) is installed to reduce soil loss and promote plant growth. Wildlife, such as snakes (suborder Serpentes), are prone to entanglement in erosion control blankets (ECBs) that contain polypropylene mesh with fused apertures. Previous reports have noted that the occurrences of entanglements are not uniform in their distribution across an ECB, but primarily occur where the edge of the mesh is exposed. We conducted an experiment to determine if modification to the installation methods of ECBs affects the likelihood of snake entanglement. We conducted entanglement trials to compare the likelihood of snake entanglement between two treatments: 1) exposed ECB edge (i.e., perimeter) and 2) buried ECB edge. Snakes were less likely to attempt to pass through the mesh on the buried edge treatment and all entanglements occurred on the exposed edge treatment. These results provide support that modification to the installation methods reduces snake entanglement in ECBs in some settings. However, we conducted our study in an experimental setting, and it should be evaluated under natural field conditions. This research can be used to inform several parties including contractors, habitat managers, and agency decision makers on additional steps that can be taken for products that fit their application needs to minimize risks to wildlife.

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