600
0.4/D 85 (subgrade) ≤ 5, so the D 85 (subgrade) must be greater than or equal to 0.08 mm; and. 7/D 50 (subgrade) ≤ 25, so the D 50 (subgrade) must be greater than or equal to 0.28 mm. Use average gradation values for the subgrade. If both criteria are met, no fabric is necessary. Otherwise, include a fabric at the bottom of the excavation.
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What Does Subgrade Mean In Construction | Storables
Compaction Techniques: Proper compaction is essential for achieving subgrade stability. Various compaction techniques, such as dynamic compaction and vibratory rollers, can be used to increase soil density and eliminate air voids. Compaction improves the load-bearing capacity and reduces the risk of settlement or deformation in the subgrade.
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Concrete Subgrades: Quick & Easy Construction …
Subgrade Compaction. Compaction is vital for achieving a stable subgrade. Use heavy machinery like rollers or plate compactors to compress the soil and subbase materials effectively. Well-compacted subgrades mitigate …
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Real-time monitoring and quality assessment of subgrade compaction…
This paper describes a monitoring and evaluation method based on intelligent compaction (IC) and artificial neural networks (ANNs) to assess the compaction quality of a highway subgrade. Field ...
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Subgrade Preparation for Concrete Slab
Proper compaction of the subgrade is vital to achieve stability and prevent future settlement issues. Compaction can be done using various techniques, including mechanical compactors or vibrating plates, depending on the soil type and moisture content.
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Intelligent Compaction Measurement Value in Variability …
Intelligent compaction (IC) is an innovative and modified technology used for quality control in subgrade digital construction. However, current intelligent compaction measurement values (ICMVs) cannot provide accurate measurement of the filling layer when the strength of the underlying layer is relatively high. Experimental field tests conducted in the cut …
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Numerical simulation of intelligent compaction for subgrade
During the compaction of a road subgrade, the mechanical parameters of the soil mass change in real time, but current research assumes that these parameters remain unchanged. In order to address this discrepancy, this paper establishes a relationship between the degree of compaction K and strain ε. The relationship between the compaction degree K …
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Numerical simulation of compaction parameters for sand …
The study uses the finite element method to simulate a new technique of highway sand embankment filling in Jianghan Plain district, which can raise the thickness of sand-filled layer from 30 cm to 70 cm and can significantly shorten the construction period based on the guarantee of sand embankment construction quality. After simulating the three compacting …
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Review on monitoring of pavement subgrade settlement: …
The most direct subgrade settlement monitoring technique is to bury stress and strain sensors inside the subgrade, such as inclinometer tubes, layered settlement rings, ... Subgrade compaction uniformity is an important aspect to ensure the engineering performance and the long-term stability of the subgrade.
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Intelligent compaction methods and quality control
The strength and resistance to plastic deformation of the soil-filling are significantly increased under compaction. The stability and safety of infrastructure like roads [1,2,3], airports [4,5,6,7,8], dams [9,10,11,12], and railways [13,14,15] rely on the roadbed or subgrade's ability to resist deformation.Therefore, the compaction quality of the filling needs to be strictly controlled …
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A Novel Method for Full-Section Assessment of High-Speed …
Abstract. The high-speed railway subgrade compaction quality is controlled by the compaction degree (K), with the maximum dry density (ρ dmax) serving as a crucial indicator for its calculation.The current mechanisms and methods for determining the ρ d max still suffer from uncertainties, inefficiencies, and lack of intelligence. These deficiencies can lead to insufficient …
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Concrete Subgrades: Quick & Easy Construction Guide (2024)
Preparation: Proper compaction and grading are essential for a reliable subgrade. The soil may be treated or stabilized to improve its bearing capacity. Subgrade Preparation Techniques Compaction. Compaction is essential to reduce voids in the soil and increase its load-bearing capacity. This is usually achieved using machines like rollers or ...
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Coupled vibratory roller and layered unsaturated subgrade …
Conventional methods for subgrade compaction quality assessment typically belong to spot tests, such as the sand replacement method and the Benkelman beam method. These methods are time-consuming and only allow for random sampling assessments of subgrade compaction quality. ... In this paper, an FFT technique at the range of −40 m −1 < ...
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Roller-integrated compaction monitoring and assessment of …
Compaction quality plays a vital role in the long-term performance of highways, thereby making quality control (QC) of compaction an essential aspect in highway projects. The prevalent approach regarding QC of compaction primarily depends on manual manipulation of compaction parameters during the construction process and sporadic testing after completion. However, …
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Section 6E-1
Subgrade soil is part of the pavement support system. Subgrade performance generally depends on three basic characteristics: 1. Strength: The subgrade must be able to support loads transmitted from the pavement structure. This load-bearing capacity is often affected by degree of compaction, moisture content, and soil type.
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Microstructure evolution of coarse-grained soil fillers during subgrade …
The lack of researches on the intrinsic microstructure evolution of coarse-grained soil fillers during subgrade compaction-operation period (SCOP), resulting in a deficiency of theoretical guidance for the lifecycle health monitoring of high-speed railway subgrade.In this paper, the self-developed intelligent vibratory compaction instrument (IVCI) was used to rapidly …
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IMPROVEMENT OF PAVEMENT SUBGRADE SOIL BY …
We can improve sub grade soil strength by applying compaction techniques. By doing this compaction process on sub grade soil the voids are going to reduce by cohesive attraction between sub grade soil particles. And we can add some admixtures like ordinary Portland cement, fly ash, quick lime, rice husk or by wood to get more strength for ...
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Artificial Neural Network–Based Intelligent Compaction …
DOI: 10.1061/(ASCE)GM.1943-5622.0001089 Corpus ID: 133909714; Artificial Neural Network–Based Intelligent Compaction Analyzer for Real-Time Estimation of Subgrade Quality @article{Imran2018ArtificialNN, title={Artificial Neural Network–Based Intelligent Compaction Analyzer for Real-Time Estimation of Subgrade Quality}, author={Syed Asif Imran and Manik …
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Quality control of subgrade soil using intelligent …
Intelligent Compaction (IC) of subgrade has been pro-posed in recent years to address the shortcomings of tra-ditional QC test methods [8–12]. Modern IC rollers are ... Two different techniques are illustrated to validate the accuracy of M ICA through two separate case studies. In the first study, FWD tests were
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Understanding the performance of expansive subgrade materials …
Subgrade compaction or densification using mechanical force is referred to as mechanical subgrade stabilisation (Afrin et al., 2017). ... Current expansive subgrade stabilisation techniques is focused on using chemical agents such as cement and lime in subgrade stabilisation. However, these chemical agents have limitations and prove to be non ...
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IMPROVEMENT OF PAVEMENT SUBGRADE SOIL BY COMPACTION TECHNIQUES
PDF | On May 2, 2018, Naveen Namala published IMPROVEMENT OF PAVEMENT SUBGRADE SOIL BY COMPACTION TECHNIQUES | Find, read and cite all the research you need on ResearchGate
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What is Subgrade in Construction?
Compaction. Technique: The method of compaction (rolling, vibrating, or tamping) depends on the soil type and project requirements. Depth: Compaction is usually done in layers to ensure uniform density throughout the subgrade. Drainage. Slope: The subgrade should be sloped to facilitate water runoff.
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Deep learning-based soil compaction monitoring: A proof …
A deep learning-based compaction monitoring technique for estimating soil stiffness is developed. ... 63.8, and 96.8 MN/m, are used, respectively; and the corresponding moduli of the subgrade reaction measured in the field experiment are K …
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Chapter Five
The approach is simple and robust for stiff-over-soft conditions (e.g., base over subbase, subbase over subgrade). If such techniques are not followed in the field, LWD moduli often will be dependent on depth of influ- ence but not exactly on the layer thickness of the constructed aggregate base/subbase.
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Continuous Monitoring of Subgrade Stiffness During Compaction
IC techniques rely on the interaction between the roller and the subgrade during compaction to determine the stiffness of the subgrade. Vibration of the roller drum during compaction is sensed using an accelerometer and the vibrations are analyzed in real-time to provide an estimate of the stiffness of the subgrade.
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Prepare Subgrade For Road Pavement: The Complete Skill …
At the beginner level, individuals are introduced to the fundamentals of subgrade preparation. They learn about soil analysis, compaction techniques, and drainage considerations. …
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EVALUATION OF HIGH ENERGY IMPACT COMPACTION …
combine to make traditional compaction techniques, and hence road construction costs, prohibitively expensive, even for ... situations where comparativel y deep subgrade soil improvement is required, as i s often recommended for …
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Automated monitoring and evaluation of highway subgrade compaction
The compaction quality of a highway subgrade is influenced by the compaction parameters and soil properties. Current practice lacks reliable models to assess this multivariate situation. This paper describes a monitoring and evaluation method based on intelligent compaction (IC) and artificial neural networks (ANNs) to assess the compaction ...
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Compaction quality evaluation of subgrade based on soil …
The compaction quality of a highway subgrade is influenced by the compaction parameters and soil properties. Current practice lacks reliable models to assess this multivariate situation. This paper describes a monitoring and evaluation method based on intelligent compaction (IC) and artificial neural networks (ANNs) to assess the compaction ...
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Advanced intelligent compaction strategy for subgrade soil …
This study proposes a subgrade compaction strategy that utilizes a heterogeneous dataset to estimate compaction quality across diverse scenarios while maintaining model …
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