Journal articles: 'Resilient modulus model'

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Ullah, Salamat, Arshad Jamal, Meshal Almoshaogeh, Fawaz Alharbi, and Jawad Hussain. "Investigation of Resilience Characteristics of Unbound Granular Materials for Sustainable Pavements." Sustainability 14, no. 11 (June 4, 2022): 6874. http://dx.doi.org/10.3390/su14116874.

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In this study, a comprehensive laboratory testing program was designed to study the resilience characteristics of unbound granular materials (aggregate base coarse) using the repeated load triaxial test (RLTT). During the experimental program, the resilient modulus of unbound granular material was examined using different moisture content levels, material gradation using Fuller’s equation, and stress levels. The results show that the moisture content, material gradation, and stress level have a major influence on the resilient modulus of unbound granular materials. Furthermore, a linear model has been developed between moisture content and the resilient modulus. The model significantly predicts the change in resilient modulus by changing moisture content. The study also aimed to improve the modified Uzan model by adding the effect of moisture content. An improved modified Uzan stress moisture model has been developed, which shows a strong relationship between the resilient modulus, stress, and moisture content. This study can be used as a benchmark for validating other numerical data.

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Yuan, Haiping, Weiqiang Li, Yixian Wang, Hang Lin, and Yan Liu. "Resilient Modulus—Physical Parameters Relationship of Improved Red Clay by Dynamic Tri-Axial Test." Applied Sciences 9, no. 6 (March 19, 2019): 1155. http://dx.doi.org/10.3390/app9061155.

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As one of the important parameters used in the analysis and design of subgrade, resilient modulus is directly related to the safety, economic and life time of subgrade structure. In this paper, the characteristics of resilient modulus of improved red clay at different additive content were studied through conducting laboratory repeated load tri-axial tests. The influence of stress state, moisture content, compactness, additive types, and content on resilient modulus were analyzed. In addition, the regression analysis of resilient modulus, was carried out referencing three existing prediction models. The results showed that the Andrei model can better fit the resilient modulus of red clay and have a higher determination coefficient. However, the Andrei model and other existing prediction models, reflect only the influence of stress state on resilient modulus, without considering the influence of moisture content, compactness and additive content. Therefore, based on the Andrei model, a comprehensive prediction model, which can reflect the influence of compactness, moisture content, additive content, and stress state on resilient modulus was introduced. Good agreement between the regression results and the measured ones demonstrated the integrative ability of the introduced model.

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Ren, Junping, and Sai K. Vanapalli. "Prediction of resilient modulus of frozen unbound road materials using soil-freezing characteristic curve." Canadian Geotechnical Journal 55, no. 8 (August 2018): 1200–1207. http://dx.doi.org/10.1139/cgj-2017-0153.

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The resilient modulus is a key parameter required in the mechanistic design of pavements. Experimental determination of the resilient modulus requires elaborate equipment for testing and requires trained personnel; for this reason, it is expensive. There are several models for predicting the resilient modulus for unbound road materials that take into account the influence of wetting and drying conditions. However, well-established models are not available for the prediction of the resilient modulus of these materials in a frozen state. In this paper, a semi-empirical model, which uses a soil-freezing characteristic curve as a tool, is proposed for predicting the variation of the resilient modulus with subzero temperature and the associated cryogenic suction for frozen soils. Experimental data on seven different pavement unbound materials were used to validate the proposed model. It is shown that the model can reasonably predict the resilient modulus of the investigated soils that are in a frozen state. More investigations on different types of soils would be useful to better understand the strengths and limitations of the proposed model.

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Mousavi, S. Hamed, Mohammed A. Gabr, and Roy H. Borden. "Subgrade resilient modulus prediction using light-weight deflectometer data." Canadian Geotechnical Journal 54, no. 3 (March 2017): 304–12. http://dx.doi.org/10.1139/cgj-2016-0062.

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Resilient modulus has been used for decades as an important parameter in pavement structure design. Resilient modulus, like other elasticity moduli, increases with increasing confining stress and decreases with increasing deviatoric stress. Several constitutive models have been proposed in the literature to calculate resilient modulus as a function of stress state. The most recent model, recommended by the Mechanistic–empirical pavement design guide (MEPDG) and used in this paper, calculates resilient modulus as a function of bulk stress, octahedral shear stress, and three fitting coefficients: k1, k2, and k3. Work in this paper presents a novel approach for predicting resilient modulus of subgrade soils at various stress levels based on light-weight deflectometer (LWD) data. The proposed model predicts the MEPDG resilient modulus model coefficients (k1, k2, and k3) directly from the ratio of applied stress to surface deflection measured during LWD testing. The proposed model eliminates uncertainties associated with needed input parameters for surface modulus (ELWD) calculation, such as the selection of an appropriate value of Poisson’s ratio for the soil layer and shape factor. The proposed model was validated with independent data from other studies reported in the literature.

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Pérez-García, Natalia, Paul Garnica-Anguas, Delwyn Fredlund, and Noe Mestas-Martínez. "A model to predict changes in resilient modulus resulting from wetting and drying." Infraestructura Vial 17, no. 30 (May 24, 2016): 23–30. http://dx.doi.org/10.15517/iv.v17i30.21940.

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The resilient modulus of a soil is an important parameter needed for pavement design. However, this parameter experiences post-compaction seasonal changes during the service life of the pavement as a result of wetting or drying of the soil during dry or rainy periods. Variations in the resilient modulus should be introduced into pavement design methodologies. Research literature shows resilient modulus results from other countries; however, the information is scarce for Mexican soils. In this paper, the authors show results of a research carried out in the laboratory to evaluate a model for the prediction of the effect of wetting and drying on the resilient modulus of soils classified as clays, silt, and sand. Several samples were prepared at optimum conditions using the Proctor standard test. Some specimens were then dried by allowing a loss of water through evaporation while others were allowed to gain water through capillarity (assumed to simulate post-compaction conditions). After the samples were conditioned to new water contents, resilient modulus tests were performed following the NCHRP 1-28A protocol. The results show that the resilient modulus can be predicted using a model which is a function of the deviator stress and confining pressure (i.e., (sd/s3) and the variation of water content from optimum water content conditions (i.e., the condition after field compaction). The R2 results when using the proposed resilient modulus model was 84.1%.

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Luan, Xiaohan, and Leilei Han. "Prediction Model of Dynamic Resilient Modulus of Unsaturated Modified Subgrade under Multi-Factor Combination." Applied Sciences 12, no. 18 (September 13, 2022): 9185. http://dx.doi.org/10.3390/app12189185.

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The objective of this research is to solve the problem of the lack of prediction methods and basis for the long-term road performance of oil shale residue-modified soil in seasonally frozen regions. This paper summarizes and expands the resilient modulus prediction methods in the related literature. Based on the measured soil–water characteristic curve (SWCC) of the compacted modified soil and the trend characteristics of dynamic resilient modulus under freeze–thaw cycles, a semi-empirical prediction model is proposed. This model was used to quantitatively forecast the resilient modulus of unsaturated modified subgrade soil after the freeze–thaw cycle in a seasonal permafrost region. The applicability and accuracy of the method were verified by dynamic resilient modulus tests of the oil shale residue-modified soil under various freeze–thaw cycles and moisture content. The results show that the model has a high degree of fit to the experimental data and is more suitable for predicting the dynamic resilient modulus of modified soil under the change of moisture and the freeze–thaw cycle compared to the existing models.

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Muhanna, A. S., M. S. Rahman, and P. C. Lambe. "Model for Resilient Modulus and Permanent Strain of Subgrade Soils." Transportation Research Record: Journal of the Transportation Research Board 1619, no. 1 (January 1998): 85–93. http://dx.doi.org/10.3141/1619-10.

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The resilient modulus and cumulative permanent strain of subgrade soils under anticipated repeated loading are important considerations for the design of a pavement against fatigue and rutting failures. A simple model was developed to evaluate the resilient modulus and accumulated permanent strain of cohesive subgrade soils under repeated loads. The empirical model was derived from the observed behavior of an A-6 cohesive soil. The model was tested against an A-5 soil. The proposed model was found to predict adequately the resilient modulus and the accumulated plastic strain for all A-6 and A-5 specimens with 90 percent confidence intervals of 0.61 and 1.4, and 0.66 and 1.39, respectively.

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Liu, Hong Xi, and Liang Zhou. "Regression Model for Resilient Modulus of Subgrade Soils in Shanghai." Advanced Materials Research 374-377 (October 2011): 1796–99. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.1796.

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Subgrade resilient modulus (MR) is very important for effective design of pavements. Several methods to estimate the resilient modulus were suggested in the past years. The main objective of this paper was to validate the correlation of MR with other physical properties of the subgrade soils. Cohesive soils representing major soil types in Shanghai were selected. The resilient modulus tests were conducted with UTM. Additional analysis was then performed to develop correlations between the model parameters and other soil properties. To verify the prediction models independently, laboratory MR tests were conducted on new subgrade soils. It was observed that the predicted MR values compared well with the laboratory measured values for the soil samples.

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Mohammad, Louay N., Baoshan Huang, Anand J. Puppala, and Aaron Allen. "Regression Model for Resilient Modulus of Subgrade Soils." Transportation Research Record: Journal of the Transportation Research Board 1687, no. 1 (January 1999): 47–54. http://dx.doi.org/10.3141/1687-06.

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Yao, Yongsheng, Junfeng Qian, Jue Li, Anshun Zhang, and Junhui Peng. "Calculation and Control Methods for Equivalent Resilient Modulus of Subgrade Based on Nonuniform Distribution of Stress." Advances in Civil Engineering 2019 (September 8, 2019): 1–11. http://dx.doi.org/10.1155/2019/6809510.

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The resilient modulus of subgrade is a design parameter of the pavement structure, which is significantly affected by the overlying load and traffic load. It is important to calculate the equivalent resilient modulus of the top surface of subgrade based on the nonuniform distribution of resilient modulus in subgrade. This paper takes the fully weathered granite soil as the research object. Firstly, the soil density of different layers of the subgrade structure is calculated by the degree of compaction of different subgrade layers. Secondly, the overlying load of each point in the subgrade is determined based on the quality of subgrade. Thirdly, the subprogram of the finite element software is compiled and redeveloped based on the elastic constitutive model, and the calculation method for the resilient modulus of each point in the subgrade under the traffic load is proposed when the convergence criterion is set up. Finally, according to the deflection equivalence of the elastic double layer and elastic half-space, the calculation and control methods for equivalent resilient modulus of the top surface of subgrade under nonuniform stress distribution are put forward, and the field verification tests are carried out. The results show that the error range between numerical calculation and field measurement of equivalent resilient modulus of subgrade is 10%. It shows that the calculation method for equivalent resilient modulus of subgrade proposed in this study is reasonable and effective. The equivalent resilient modulus of subgrade decreases with the increase of traffic load. And the resilient modulus of subgrade soil increases with the increase of subgrade depth. The resilient modulus of subgrade soil has a significant impact on the equivalent resilient modulus of subgrade after the overlaying gravel layer. The equivalent resilient modulus of the subgrade with the gravel layer increases with the increase of the resilient modulus of the subgrade soil.

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Chu, Xuanxuan. "A Review on the Resilient Response of Unsaturated Subgrade Soils." Advances in Civil Engineering 2020 (February 27, 2020): 1–11. http://dx.doi.org/10.1155/2020/7367484.

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Considering the great contribution of subgrade modulus to the overall performance of roads or railways, it is crucial to provide the best prediction of resilient modulus for their foundations. Incorporating the seasonal variation of moisture content, the resilient modulus variation of unsaturated soils will be accurately predicted. This paper aims to introduce and discuss the knowledge about resilient response of unsaturated soils and emphasize the effects of humidity. A literature review on resilient response of unsaturated soils is presented based on the previous studies. The affecting factors (i.e., wetting and drying, moisture content, and matric suction) were discussed. The prediction model development of the resilient response of unsaturated soils was presented. The limitations and advantages of the model were analyzed and compared. It reveals that the current models were limited regarding stress conditions, moisture content, matric suction, and soil types, and further studies are still needed to achieve a better understanding of resilient response of unsaturated soils.

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Yang, Shu-Rong, Wei-Hsing Huang, and Yu-Tsung Tai. "Variation of Resilient Modulus with Soil Suction for Compacted Subgrade Soils." Transportation Research Record: Journal of the Transportation Research Board 1913, no. 1 (January 2005): 99–106. http://dx.doi.org/10.1177/0361198105191300110.

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The variations of resilient modulus with the postconstruction moisture content and soil suction for cohesive subgrade soils were evaluated. In particular, the effects of relative compaction of the subgrade on the suction and resilient modulus were investigated. To simulate subgrade soils at in-service conditions, soil specimens were compacted at various relative compactions and optimum moisture content and then saturated to equilibrium moisture content to test for resilient modulus and soil suction. The filter paper method was used to measure the total and matric suctions of two cohesive soils. Test findings demonstrated that resilient modulus correlated better with the matric suction than with total suction. Matric suction was found to be a key parameter for predicting the resilient modulus of cohesive subgrade soils. A prediction model incorporating deviator stress and matric suction for subgrade soil resilient modulus was established.

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Flintsch, Gerardo W., Imad L. Al-Qadi, Youngjin Park, Thomas L. Brandon, and Alexander Appea. "Relationship Between Backcalculated and Laboratory-Measured Resilient Moduli of Unbound Materials." Transportation Research Record: Journal of the Transportation Research Board 1849, no. 1 (January 2003): 177–82. http://dx.doi.org/10.3141/1849-19.

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The resilient moduli of an unbound granular subbase (used at the Virginia Smart Road) obtained from laboratory testing were compared with those backcalculated from in situ falling weight deflectometer deflection measurements. Testing was performed on the surface of the finished subgrade and granular subbase layer shortly after construction. The structural capacity of the constructed subgrade and the depth to a stiff layer were computed for 12 experimental sections. The in situ resilient modulus of the granular subbase layer (21-B) was then back-calculated from the deflections measured on top of that layer. The back-calculated layer moduli were clearly stress-dependent, showing an exponential behavior with the bulk stress in the center of the layer. Resilient modulus test results of laboratory-compacted specimens confirmed the stress dependence of the subbase material modulus. Three resilient modulus models were fitted to the data. Although all three models showed good coefficients of determination ( R2 > 90%), the K-θ model was selected because of its simplicity. The correlation between field-backcalculated and laboratory-measured resilient moduli was found to be strong. However, when the stress in the middle of the layer was used in the K-θ model, a shift in the resilient modulus, θ, was observed. This finding suggests that a simple shift factor could be used for the range of stress values considered.

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Maher, M. H., W. J. Papp, and N. Gucunski. "Measurement of Soil Resilient Properties Using Noncontacting Proximity Sensors." Transportation Research Record: Journal of the Transportation Research Board 1548, no. 1 (January 1996): 16–23. http://dx.doi.org/10.1177/0361198196154800103.

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The utility of noncontacting proximity sensors for the measurement of small strains in resilient modulus tests is evaluated. The proximity sensor measurements of resilient modulus were compared with those obtained from linear variable differential transformers. The important issue of granular soil sample preparation and its effect on the magnitude of resilient modulus was evaluated. Two methods were proposed to facilitate sample preparation and to provide good contact between the soil and the loading platen. The effect of conditioning sequence on sample integrity was also investigated for the two proposed methods of compaction. In addition to the experimental program, a number of constitutive models, used for prediction of resilient modulus of granular soils, were examined; and model predictions were compared with the test data.

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Hu, Chun Hua. "Prediction of Resilient Modulus for Hot Mix Asphalt Based on Artificial Neural Network." Advanced Materials Research 304 (July 2011): 18–23. http://dx.doi.org/10.4028/www.scientific.net/amr.304.18.

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Resilient modulus of material is an important parameter for pavement structure design and analysis. However it is very tedious to get this parameter for hot mixture asphalt in laboratory. Moreover it takes long time to do experiments. In this paper, artificial neural network (ANN) is applied to predict to resilient modulus for hot mixture asphalt. A neural network model is constructed and trained plenty of times with selected test data until precision meets requirement. Then the model is used to predict resilient modulus for hot mix asphalt. Result of contrast prediction with test data shows that forecast precision is high. This provides a new method to predict resilient modulus for hot mixture asphalt.

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Arshad, Ahmad Kamil, Md Diah J, and Salah Khalil. "Modelling Workability of Asphalt concrete Performance at different Temperatures using A Statistical Model." International Journal of Engineering & Technology 2, no. 1 (March 3, 2013): 77. http://dx.doi.org/10.14419/ijet.v2i1.674.

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In this study, a workability model is used to predict the values of Torque in relation to mix and compaction by Temperature, Gyration, Resilient Modulus, Stability and Flow. The data are obtained from workability-measuring devices developed by the authors. The value of R2 implies that about 95 % variation in the values of Torque can be explained by the variation in mixing and compaction according to Temperature, Gyration, and Resilient Modulus. The regression model as a whole shows that while the value of Torque is largely influenced by Compaction, Mixing Temperature and Gyration; Resilient Modulus, Stability and Flow are not significant determinants of workability. The paper recommends that the effect of workability on the performance of Asphalt concrete should be taken very seriously during the design.

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Li, Zhi Yong, Jing Rong Zou, and Cheng Dong. "Study on Prediction Model of Dynamic Resilient Modulus of Cohesive Subgrade Soils Considering Moisture Variation." Applied Mechanics and Materials 488-489 (January 2014): 411–16. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.411.

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The matric suctions were measured by the filter paper method, and the parameters of soil-water characteristic curve were obtained. In order to investigate the effect of moisture content on cohesive subgrade soils dynamic resilient modulus, a series of dynamic-triaxial test were carried out. Based on the matric suctions measured by the filter paper method, the relationship between dynamic resilient modulus and matric suctions were analyzed. The study demonstrated that the dynamic resilient modulus values decrease with the increase of circular deviator stress and moisture content, in reverse of matric suctions. Considering that the dynamic resilient modulus is a function of deviator stress and bulk stress, based on the present three parameters compound constitutive model which reflects the effect of bulk stress and deviator stress, the effect of matric suctions which could indirectly reflect the effect of moisture content was introduced. And then the prediction model incorporating the effect of stress and moisture for cohesive subgrade soils was established. The model was utilized for experimental data regression analysis, a high coefficient of determination shows that the model is accurate and credible. The prediction models not only can evaluate the long-term performance of subgrade soil in Southern China's rainy areas, but also can provide parameters for the pavement design based on dynamic method.

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Salour, Farhad, Sigurdur Erlingsson, and Claudia E. Zapata. "Modelling resilient modulus seasonal variation of silty sand subgrade soils with matric suction control." Canadian Geotechnical Journal 51, no. 12 (December 2014): 1413–22. http://dx.doi.org/10.1139/cgj-2013-0484.

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The resilient modulus of unbound materials is an important parameter in the mechanistic design of pavements. Although unbound layers are frequently in a partially saturated state, a total stress approach is conventionally used in modeling the material behaviour, and therefore pore pressure effects are not considered. In fine-grained unbound materials, the saturation state can affect their mechanical behaviour due to pore pressure effects. In this study a modified test procedure and a predictive resilient modulus model that takes into account the subgrade soil matric suction as a stress state variable is presented. Two different silty sand subgrade materials were tested in unsaturated conditions using a series of repeated load triaxial tests under controlled pore suction conditions to study its influence on the resilient modulus. The test data were further used to obtain the resilient modulus model regression parameters that account for moisture content variations through the matric suction parameter. Generally, the prediction model could effectively capture the resilient modulus behaviour of the subgrades with respect to changes in the normal stress state and the matric suction. Given the completeness of this method, this prediction model is recommended as an improved approach in capturing the moisture content effects on the material stiffness properties.

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Tamošiūnas, Tadas, and Šarūnas Skuodis. "Predictive Stress Modeling of Resilient Modulus in Sandy Subgrade Soils." Infrastructures 8, no. 2 (February 8, 2023): 29. http://dx.doi.org/10.3390/infrastructures8020029.

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The mechanical properties of pavement materials are crucial to the design and performance of flexible pavements. One of the most commonly used measures of these properties is the resilient modulus (Er). Many different models were developed to predict the resilient modulus of coarse soils, which are based on the states of stresses and the physical and mechanical properties of the soil. The unconsolidated unsaturated drained cyclic triaxial tests were performed for three variously graded and three well-graded sand specimens to determine the resilient modulus, and to perform predictive modeling using the K-θ, Rahim and George, Uzan, and Universal Witczak models. Obtained Er values directly depended on the confining pressure and deviatoric stress values used during the test. The Octahedral Shear Stress (OSS) model, proposed by the authors of the paper, predicts the resilient modulus with a coefficient of determination (R2) ranging from 0.85 to 0.99. The advantage of the model is the use of small-scale data tables, meaning fixed K1 and K2 regression coefficients, and it can be assigned to a specific specimen type without the need to determine them using the specific deviatoric and confining stresses.

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Chowdhury, S. M. Robinur Mohshin, Emad Kassem, Hamza Alkuime, Debakanta Mishra, and Fouad M. S. Bayomy. "Summary Resilient Modulus Prediction Model for Unbound Coarse Materials." Journal of Transportation Engineering, Part B: Pavements 147, no. 3 (September 2021): 04021035. http://dx.doi.org/10.1061/jpeodx.0000289.

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Xu, An Hua, and Jian Hong Fang. "Study on Roadbed Soil Dynamic Resilient Modulus Test." Advanced Materials Research 671-674 (March 2013): 1245–53. http://dx.doi.org/10.4028/www.scientific.net/amr.671-674.1245.

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This paper draws on the successful experience from domestic and abroad researches, testing repeatedly of powder subgrade with load triaxial tests, analyzing the relationship between the subgrade soil resilient modulus, deviatoric stress, water content and degree of compaction. At the same time, conducting corresponded roadbed soil resilient modulus forecast model, and qualifying its correctness of test data model.

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Lu, Zheng, Yang Zhao, Shaohua Xian, and Hailin Yao. "Experimental Study on Dynamic Resilient Modulus of Lime-Treated Expansive Soil." Advances in Materials Science and Engineering 2020 (January 27, 2020): 1–10. http://dx.doi.org/10.1155/2020/3272681.

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Dynamic resilient modulus is the design index of highway subgrade design code in China, which is significantly affected by the traffic loads and environmental changes. In this study, dynamic triaxial tests were conducted to investigate the influence of moisture content, compaction degree, cyclic deviator stress, and confining pressure on lime-treated expansive soil. The suitability of UT-Austin model to lime-treated expansive soils was verified. The results indicate that the dynamic resilient modulus of lime-treated expansive soils increases nonlinearly with the increase of compaction degree, while decreases nonlinearly with the increase of dynamic stress level. The dynamic resilient modulus decreases linearly with the increase of moisture content and increases linearly with the increase of confining pressure. Moreover, the moisture content has a more significant effect on the dynamic resilient modulus of lime-treated expansive soil. Therefore, it is necessary to ensure the stability of soil humidity state and its excellent mechanical properties under long-term cyclic loading for the course of subgrade filling and service. Finally, the calculated results of the UT-Austin model for dynamic resilient modulus show a good agreement with the test results.

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Hu, Meng Ling, Hai Lin Yao, Jie Liu, and Zheng Lu. "Influence of Variation of Groundwater Level on Deformation of Subgrade Based on Hydromechanical Coupling." Advanced Materials Research 457-458 (January 2012): 30–33. http://dx.doi.org/10.4028/www.scientific.net/amr.457-458.30.

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Deformation of subgrade caused by variation of groundwater level is a problem of hydromechanical coupling. The coupling mechanism of seepage and deformation of subgrade was analyzed, and a model of hydromechanical coupling was then established. The resilient modulus of the model is related to the water content and compactness of subgrade soil. The relationship between them was obtained based on laboratory tests, and was employed to research the influence of rise of groundwater level on resilient modulus and deformation of subgrade. The results showed that the rise of water level had great influence on resilient modulus of subgrade, and the deformation of subgrade can’t be neglected.

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Yan, Xin, Wei Zhan, Zhi Hu, Yiqiang Yu, and Danqiang Xiao. "Experimental Study on the Effect of Compaction Work and Defect on the Strength of Soil-Rock Mixture Subgrade." Advances in Materials Science and Engineering 2021 (June 8, 2021): 1–13. http://dx.doi.org/10.1155/2021/5533590.

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Soil-rock mixture is a common filling material for earth dam and subgrade. In this study, research concerned on the evolution law of engineering characteristics of soil-rock mixture under different factors and the effect of defect on subgrade strength, and geotechnical tests were carried out to analyze the influence of different factors on engineering characteristics of soil-rock mixture in the study, and the physical model was carried out to analyze the effect of different compaction works on the resilient modulus, and the influence of defect on the strength was explored by manually preset loose body. The test results showed that (1) when the soil-rock mixture was graded, P = 78, the moisture content was 14%, and the engineering characteristics were optimal; (2) there was a positive correlation between compaction times and resilient modulus, and the stress transferred from the subgrade to soil was linearly distributed under the good condition of compactness; and (3) the existence of loose body not only reduces the modulus of resilience but also affects the stress transfer; the larger the loose body, the lower the resilient modulus and the greater the stress transfer.

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Azam, A. M., D. A. Cameron, and M. M. Rahman. "Model for prediction of resilient modulus incorporating matric suction for recycled unbound granular materials." Canadian Geotechnical Journal 50, no. 11 (November 2013): 1143–58. http://dx.doi.org/10.1139/cgj-2012-0406.

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This paper presents experimental results on the effect of matric suction on the resilient modulus of four recycled unbound granular materials. The recycled materials were prepared at moisture contents ranging between 70% and 90% of optimum moisture content (OMC) and tested in a repeated load triaxial test (RLTT) apparatus under various stress regimes. Soil-water characteristic curves (SWCC) were established for each material by preparing samples at various moisture contents and measuring matric suction with filter papers. To obtain the wet end of the SWCC, further samples were conditioned on a tension plate at suctions controlled by the hanging water column method. Some published models for prediction of resilient modulus were applied to the experimental data, but the correlations were unsatisfactory generally, and so an improved model was sought. Subsequently, a model with four terms and six constants was developed, which followed the general power law. A single set of material constants was found for all recycled materials to provide satisfactory predictions of resilient modulus (R2 = 0.88), over a wide range of stresses and moisture states.

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Lee, Junhwan, Jihwan Kim, and Beongjoon Kang. "Normalized Resilient Modulus Model for Subbase and Subgrade Based on Stress-Dependent Modulus Degradation." Journal of Transportation Engineering 135, no. 9 (September 2009): 600–610. http://dx.doi.org/10.1061/(asce)te.1943-5436.0000019.

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Konrad, J. M. "The use of tangent stiffness to characterize the resilient response of unbound crushed aggregates." Canadian Geotechnical Journal 43, no. 11 (November 1, 2006): 1117–30. http://dx.doi.org/10.1139/t06-079.

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Repeated-load triaxial tests were conducted on crushed granitic base-course material to study the resilient response under different stress paths and compaction states. It has been established that the resilient response of this prestrained unbound granular material is best defined in terms of tangent stiffness (Et) and vertical stress (σv). The data also revealed the existence of a threshold value of tangent stiffness that is essentially dependent on initial confining stress for a given compaction state. When the tangent modulus exceeds this threshold value, a unique relationship between tangent stiffness and vertical stress exists for mobilized shear resistance ratios less than 0.4. This Et–σv relationship is independent of stress path. A simple power law model can be used to predict the resilient response of unbound base-course material and an approximate value of resilient modulus for any desired stress path and initial stress condition. The use of the tangent stiffness – vertical stress model for pavement design appears to be very promising.Key words: granular, material, resilient modulus, triaxial, stress path.

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Li, Cong, and Wei Lan. "Study on Moisture Modification for Resilient Modulus of Subgrade." Applied Mechanics and Materials 361-363 (August 2013): 1460–66. http://dx.doi.org/10.4028/www.scientific.net/amm.361-363.1460.

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Subgrade resilient modulus of 3 typical soils, namely sand, silt and clay, have been measured under different conditions of 2 target dry density and 3 target water content by triaxial repeated-loading test. Analysis has been focused on the effect law of subgrade moisture and compaction for resilient modulus based on test results. Subgrade moisture has some impact on resilient modulus of test soils, especially on that of fine-grained soils. The influence degree of subgrde compaction depends on soil group. Coefficient of moisture modification has been introduced to characterize relationship between subgrade moisture and resilient modulus. Two-parameter Logistic model with inflexion control has been proposed according to the following basic rule. Coefficient of moisture modification usually increases or decreases along with the decrement or increment of subgrade moisture. And then variety rate of coefficient becomes small in state of high or low water content.

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Mousa, E., A. Azam, M. El-Shabrawy, and S. M. El-Badawy. "Laboratory characterization of reclaimed asphalt pavement for road construction in Egypt." Canadian Journal of Civil Engineering 44, no. 6 (June 2017): 417–25. http://dx.doi.org/10.1139/cjce-2016-0435.

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This paper presents the engineering characteristics of reclaimed asphalt pavement (RAP), blended with virgin aggregate for unbound base and subbase layers. The proportions of RAP were 0%, 20%, 60%, 80%, and 100% by total mass of the blend. The experimental laboratory testing included index properties such as gradation, modified Proctor compaction, California Bearing Ratio, and hydraulic conductivity. Repeated load resilient modulus testing was conducted on the blends. The impact of load duration on resilient modulus was also investigated. A strong inverse trend was found between resilient modulus and California Bearing Ratio. An accurate model was proposed for the prediction of the resilient modulus as a function of stress state and reclaimed asphalt pavement percentage with coefficient of determination of 0.94. Finally, multilayer elastic analysis of typical pavement sections with the base layer constructed of virgin aggregate and reclaimed asphalt pavement blends showed good performance.

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Puppala, Anand J., Louay N. Mohammad, and Aaron Allen. "Engineering Behavior of Lime-Treated Louisiana Subgrade Soil." Transportation Research Record: Journal of the Transportation Research Board 1546, no. 1 (January 1996): 24–31. http://dx.doi.org/10.1177/0361198196154600103.

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Lime stabilization is often used to treat subgrade soils when they are soft and cohesive in nature. A study was conducted to investigate the engineering behavior, including the resilient and strength behaviors, of a lime-treated subgrade soil. The lime treatment procedure was adapted from the specifications of the Louisiana Department of Transportation and Development. Silty clay, a soil often found in Louisiana subgrades, is used as a base soil. A summary of various engineering properties of a lime-treated soil from resilient modulus, unconfined compression strength, and California bearing ratio (CBR) tests conducted at five moisture content and dry density levels is provided. Tests were also performed on the raw soil without lime treatment, and these results were compared with those of tests with the lime-treated soil. The comparisons indicate that the present lime treatment method results in an increase in strength and resilient modulus properties and a decrease in plasticity characteristics and plastic strains. A regression model with three constants was used to analyze the resilient modulus test results. The model constants are presented as functions of soil properties. Resilient modulus correlations that use either CBR or unconfined compression strength, moisture content, dry density, degree of compaction, and stresses as dependent attributes are developed.

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Hilal, Miami. "PREDICTION OF RESILIENT MODULUS MODEL FOR WEARING ASPHALT PAVEMENT LAYER." Kufa Journal of Engineering 09, no. 4 (November 25, 2018): 65–87. http://dx.doi.org/10.30572/2018/kje/090405.

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Ozsahin, Talat Sukru, and Seref Oruc. "Neural network model for resilient modulus of emulsified asphalt mixtures." Construction and Building Materials 22, no. 7 (July 2008): 1436–45. http://dx.doi.org/10.1016/j.conbuildmat.2007.01.031.

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De Souza, Wana Maria, Antonio Júnior Alves Ribeiro, and Suelly Helena De Araújo Barroso. "Estimating the resilient modulus of subgrade materials using visual inspection." TRANSPORTES 30, no. 3 (December 14, 2022): 2738. http://dx.doi.org/10.14295/transportes.v30i3.2738.

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The definition of the Resilient Modulus (MR) of subgrade soils is essential for the reliable implementation of mechanistic-empirical pavement design. The MR of the soil is measured through repeated triaxial load tests which require expensive equipment and complex analyses. This reinforces the need to develop accurate statistical models for the prediction of the MR of the subgrade soil to be used for paving highways, especially in developing countries, such as Brazil, where financial resources are limited. The present study used artificial neural networks (ANNs) to create a model for the prediction of the MR of subgrade soils based on a visual-manual classification. For this, the results of MR tests conducted on samples of different soils from northeastern Brazil were used to develop an ANNs model for the prediction of the MR. The results demonstrate that ANNs can predict reliably the MR of soils, with a good degree of correlation in comparison with the laboratory test data. These findings support the use of the ANN model as a cost-effective approach for the preliminary evaluation of subgrade soils for highway pavement design in northeastern Brazil.

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Speir, Richard H., and Matthew W. Witczak. "Use of Shredded Rubber in Unbound Granular Flexible Pavement Layers." Transportation Research Record: Journal of the Transportation Research Board 1547, no. 1 (January 1996): 96–106. http://dx.doi.org/10.1177/0361198196154700114.

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The major objective of the research was to conduct a study into the feasibility of using shredded rubber as a partial replacement for aggregate within conventional base and subbase materials in a flexible pavement system. A graded aggregate base and sand subbase meeting specifications for the Maryland State Highway Administration were used. The rubber used in the study consisted of a shredded product with 60 to 70 percent retained on a 9.5-mm (⅜-in.) sieve. This size was selected because of the relatively inexpensive cost to produce it and because of its adaptability to an aggregate blend. Modified and standard Proctor, California bearing ratio (CBR), and resilient modulus tests were conducted on the base/subbase-rubber blends with up to 15 percent rubber content by weight. The aggregate base blend resulted in significant decreases in both CBR and nonlinear resilient modulus at 15 percent rubber. These significant reductions led the authors to conclude that the use of shredded rubber in a dense-graded aggregate base course is not feasible. In contrast, the sand-subbase blends resulted in insignificant changes to the CBR, friction angle, permeability, and resilient modulus at higher rubber percentages. It was concluded that the sand-rubber sub-base exhibits little change compared with the virgin sand-subbase material. As a result the use of shredded rubber may be a technically feasible alternative in the construction process. Finally, two constitutive models were used in the resilient modulus analysis: the conventional K1, K2 model and a universal model incorporating an octahedral stress term (k1, k2, k3 model). Direct comparisons revealed greatly improved predictability and accuracy with the universal model for assessing the nonlinear behaviors of both aggregate types evaluated.

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Sas, Wojciech, Andrzej Głuchowski, and Maciej Miturski. "Studies on resilient modulus value from cyclic loading tests for cohesive soil." Annals of Warsaw University of Life Sciences – SGGW. Land Reclamation 49, no. 2 (June 1, 2017): 117–27. http://dx.doi.org/10.1515/sggw-2017-0010.

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Abstract In this article the cyclic CBR test as a reference method in determination of resilient modulus (Mr) is confronted with results of cyclic triaxial and unconfined uniaxial cyclic test. The main idea of conducted experiments is establish relationship between cyclic loading tests in testing of natural subsoil and road materials. The article shows results of investigation on cohesive soil, namely sandy silty clay, commonly problematic soil in Poland. The results of repeated loading triaxial test resilient modulus were displayed in order to compare them with cyclic CBR test results by using the Mr–Ө model. Some empirical correlation between factors obtained from triaxial test or uniaxial unconfined cyclic test and cyclic CBR test was introduced here. The behavior of resilient modulus was also examined in this paper.

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Pahno, Steve, Jidong J. Yang, and S. Sonny Kim. "Use of Machine Learning Algorithms to Predict Subgrade Resilient Modulus." Infrastructures 6, no. 6 (May 21, 2021): 78. http://dx.doi.org/10.3390/infrastructures6060078.

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Modern machine learning methods, such as tree ensembles, have recently become extremely popular due to their versatility and scalability in handling heterogeneous data and have been successfully applied across a wide range of domains. In this study, two widely applied tree ensemble methods, i.e., random forest (parallel ensemble) and gradient boosting (sequential ensemble), were investigated to predict resilient modulus, using routinely collected soil properties. Laboratory test data on sandy soils from nine borrow pits in Georgia were used for model training and testing. For comparison purposes, the two tree ensemble methods were evaluated against a regression tree model and a multiple linear regression model, demonstrating their superior performance. The results revealed that a single tree model generally suffers from high variance, while providing a similar performance to the traditional multiple linear regression model. By leveraging a collection of trees, both tree ensemble methods, Random Forest and eXtreme Gradient Boosting, significantly reduced variance and improved prediction accuracy, with the eXtreme Gradient Boosting being the best model, with an R2 of 0.95 on the test dataset.

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Nataatmadja, A., and A. K. Parkin. "Characterization of granular materials for pavements." Canadian Geotechnical Journal 26, no. 4 (November 1, 1989): 725–30. http://dx.doi.org/10.1139/t89-083.

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For design and analysis of flexible pavements, a simple elastic model that does not require cumbersome calculation and also can rank materials according to their performance is clearly desirable. Early studies indicated that the resilient modulus of a granular material can be taken to be a function of the first invariant of stress, θ, although there is evidence that it is also dependent on the repeated deviator stress, qr. The limitations of some earlier models are discussed herein and a simple model for granular materials is proposed. The model is empirical in nature and based on repeated load triaxial testing with constant confining pressure. The application of this model in situations where the confining pressure is pulsed in phase with the deviator stress is also discussed. Key words: repeated load, triaxial test, resilient modulus, granular materials, modelling, pavement.

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Elias, Mohammed B., and Hani H. Titi. "Evaluation of Resilient Modulus Model Parameters for Mechanistic–Empirical Pavement Design." Transportation Research Record: Journal of the Transportation Research Board 1967, no. 1 (January 2006): 89–100. http://dx.doi.org/10.1177/0361198106196700110.

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Xiao, Yuanjie, Kunfeng Kong, Umar Faruk Aminu, Zhiyong Li, Qiang Li, Hongwei Zhu, and Degou Cai. "Characterizing and Predicting the Resilient Modulus of Recycled Aggregates from Building Demolition Waste with Breakage-Induced Gradation Variation." Materials 15, no. 7 (April 5, 2022): 2670. http://dx.doi.org/10.3390/ma15072670.

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Building demolition waste (BDW) has been massively stockpiled due to increasingly rapid urbanization and modernization. The use of recycled BDW as unbound granular base/subbase materials is among the sustainable, cost-effective, and environmentally friendly pavement construction alternatives. The resilient modulus is an important mechanical property of BDW-derived aggregates and mechanistic design input of pavements incorporating BDW. This paper presents the results of a comprehensive laboratory study on the shear strength and resilient modulus characteristics of BDW-derived aggregate materials. A series of monotonic triaxial compression tests and repeated-load triaxial (RLT) tests were conducted with five different gradations representing particle breakage and different stress paths. The apparent cohesion and internal friction angle of recycled BDW aggregates under consolidated drained conditions ranged from 35.3 to 57.5 kPa and from 30.2° to 54.3°, respectively. The apparent cohesion and internal friction angle also increased and decreased non-linearly with the increasing relative content of fine particles, respectively. The resilient modulus of recycled BDW aggregates gradually decreased with increasing relative content of fine particles at the same stress level. Both the deviator stress and confining pressure exhibited significant influences on the resilient modulus, while the effect of confining pressure was more profound. Based on laboratory testing data, a mechanistic-empirical model was developed to predict the resilient modulus of recycled BDW aggregates from gradation and stress-state variables. The findings could be useful for extended engineering applications of BDW in unbound granular pavement base/subbase construction.

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Tutumluer, Erol, and Roger W. Meier. "Attempt at Resilient Modulus Modeling Using Artificial Neural Networks." Transportation Research Record: Journal of the Transportation Research Board 1540, no. 1 (January 1996): 1–6. http://dx.doi.org/10.1177/0361198196154000101.

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The pitfalls inherent in the indiscriminate application of artificial neural networks to numerical modeling problems are illustrated. An example is used of an apparently successful (but ultimately unsuccessful) attempt at training a neural network constitutive model for computing the resilient modulus of gravels as a function of stress state and various material properties. Issues such as the quantity and quality of data needed to successfully train a neural network are explored, and the importance of an independent test set to verify network performance is examined.

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Gu, Chuan, Xingchi Ye, Jun Wang, Yuanqiang Cai, Zhigang Cao, and Tingting Zhang. "Resilient behavior of coarse granular materials in three-dimensional stress state." Canadian Geotechnical Journal 57, no. 9 (September 2020): 1280–93. http://dx.doi.org/10.1139/cgj-2019-0353.

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The traffic-induced cyclic stresses on the road base and subbase courses are usually in three-dimensional stress state, while so far most laboratory studies have focused on the deformation behavior of base and subbase layers in axisymmetric stress state. This study investigates the three-dimensional resilient behavior of coarse granular base and subbase materials based on a true triaxial apparatus. The factors of effective confining pressure, [Formula: see text], amplitude of cyclic shear stress, qampl, coefficient of cyclic intermediate principal stress, bcyc, and fines content are involved. Test results indicate that the increase of either [Formula: see text] or qampl leads to a nonlinear growth of resilient modulus with a decreasing growth rate. bcyc, which is proposed to represent the coupling of cyclic major and intermediate principal stresses, is found to have a promotion effect on the resilient stiffness, and the promotion effect tends to be enhanced by the increase of qampl. A modified model is established to predict the resilient modulus of coarse granular materials in three-dimensional stress state. There appears to exist a critical value of fines content, at which the variation trend of resilient modulus is changed from increasing to decreasing, and the critical fines content is related to both [Formula: see text] and bcyc.

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Yao, Yongsheng, Jianlong Zheng, Junhui Zhang, Junhui Peng, and Jue Li. "Model for Predicting Resilient Modulus of Unsaturated Subgrade Soils in South China." KSCE Journal of Civil Engineering 22, no. 6 (May 18, 2018): 2089–98. http://dx.doi.org/10.1007/s12205-018-1703-1.

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Saleh, Huda Mahdi, and Amjad H. Albayati. "Model Development for the Prediction of the Resilient Modulus of Warm Mix Asphalt." Civil Engineering Journal 6, no. 4 (April 1, 2020): 702–13. http://dx.doi.org/10.28991/cej-2020-03091502.

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Increasing material prices coupled with the emission of hazardous gases through the production and construction of Hot Mix Asphalt (HMA) has driven a strong movement toward the adoption of sustainable construction technology. Warm Mix Asphalt (WMA) is considered relatively a new technology, which enables the production and compaction of asphalt concrete mixtures at temperatures 15-40 °C lower than that of traditional hot mix asphalt. The Resilient modulus (Mr) which can be defined as the ratio of axial pulsating stress to the corresponding recoverable strain, is used to evaluate the relative quality of materials as well as to generate input for pavement design or pavement evaluation and analysis. Based on the aforementioned preface, it is possible to conclude that there is a real need to develop a predictive model for the resilient modulus of the pavement layer constructed using WMA. Within the experimental part of this study, 162 cylindrical specimens of WMA were prepared with dimensions of 101.6 mm in diameter and 63.5 mm in thickness. The specimens were subjected to the indirect tension test by pneumatic repeated loading system (PRLS) to characterize the resilient modulus. The test conditions (temperature and load duration) as well as mix parameters (asphalt content, filler content and type, and air voids) are considered as variables during the specimen’s preparation. Following experimental part, the statistical part of the study includes a model development to predict the Mr using Minitab vs 17 software. The coefficient of determination (R2) is 0.964 for the predicted model which is referred to a very good relation obtained. The Mr value for the WMA is highly affected by the temperature and moderately by the load duration, whereas the mix parameters have a lower influence on the Mr.

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Konrad, J. M., and Ph D. Nguyen. "Implementation of the tangent modulus – vertical stress (Et–σv) model for flexible pavements analysis." Canadian Geotechnical Journal 43, no. 11 (November 1, 2006): 1131–43. http://dx.doi.org/10.1139/t06-060.

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A recently developed nonlinear elastic model of granular material, referred to as the tangent modulus – vertical stress (Et–σv) model, was implemented into a finite element numerical solver FlexPDE. The FlexPDE program was used to compare deflection predictions with actual plate-load test data from a site near Québec City. The proposed Et–σv model performed well and led to excellent predictions for load levels of 40, 50, and 70 kN. Comparison with predictions using the Uzan model suggests that constitutive models of granular materials are best expressed in terms of vertical stress rather than mean stress for the prediction of elastic pavement response for field conditions.Key words: granular material, resilient modulus, triaxial test, plate-loading test, finite element.

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Han, Zhong, and Sai K. Vanapalli. "Model for predicting resilient modulus of unsaturated subgrade soil using soil-water characteristic curve." Canadian Geotechnical Journal 52, no. 10 (October 2015): 1605–19. http://dx.doi.org/10.1139/cgj-2014-0339.

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Soil suction (ψ) is one of the key factors that influence the resilient modulus (MR) of pavement subgrade soils. There are several models available in the literature for predicting the MR–ψ correlations. However, the various model parameters required in the existing models are generally determined by performing regression analysis on extensive experimental data of the MR–ψ relationships, which are cumbersome, expensive, and time-consuming to obtain. In this paper, a model is proposed to predict the variation of the MR with respect to the ψ for compacted fine-grained subgrade soils. The information of (i) the MR values at optimum moisture content condition (MROPT) and saturation condition (MRSAT), which are typically determined for use in pavement design practice; (ii) the ψ values at optimum moisture content condition (ψOPT); and (iii) the soil-water characteristic curve (SWCC) is required for using this model. The proposed model is validated by providing comparisons between the measured and predicted MR–ψ relationships for 11 different compacted fine-grained subgrade soils that were tested following various protocols (a total of 16 sets of data, including 210 testing results). The proposed model was found to be suitable for predicting the variation of the MR with respect to the ψ for all the subgrade soils using a single-valued model parameter ξ, which was found to be equal to 2.0. The proposed model is promising for use in practice, as it only requires conventional soil properties and alleviates the need for experimental determination of the MR–ψ relationships.

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Qian, Junfeng, Yongsheng Yao, Jue Li, Hongbin Xiao, and Shenping Luo. "Resilient Properties of Soil-Rock Mixture Materials: Preliminary Investigation of the Effect of Composition and Structure." Materials 13, no. 7 (April 3, 2020): 1658. http://dx.doi.org/10.3390/ma13071658.

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The physical composition and stress state of soil-rock mixture (SRM) materials have a crucial influence on their mechanical properties, and play a vital role in improving the performance of subgrade. To reveal the resilient behavior and mesostructure evolution of SRM materials, triaxial tests and discrete element method (DEM) numerical analysis have been carried out. In the triaxial test section, the mechanical response of SRM materials was investigated by preparing samples under different stress states and physical states and conducting triaxial tests on samples. Simultaneously, a new irregular particle modeling method was developed and applied to the discrete element modeling process to analyze the mesostructure evolution of SRM materials under cycling loading. First, a cyclic triaxial test of SRM material is performed on the SRM material, and the effects of bulk stress, octahedral shear stress and rock content on the resilient modulus of the SRM material are analyzed. It is revealed that the resilient modulus increases with increasing bulk stress and rock content, and decreases with increasing octahedral shear stress. Based on a new resilient modulus prediction model, the relationships among the rock content, stress state and resilient modulus are established. Then, based on an improved DEM modeling method, a discrete element model of the SRM is established, and the influence of rock content on coordination number and mesostructure evolution of the SRM is analyzed. The results show that in SRM materials, the increase of crushed rock changes the mesostructure of the SRM material. With the increase of rock content, the internal contact force changes from “between soil and rock” to “between rocks”, and the skeleton formed in the rocks gradually develops overall stiffness. Under the condition of low stress, the anisotropy of the SRM material is mainly caused by the shape and grade distribution of crushed rock. The induced anisotropy caused by the change of stress state has little effect on its mechanical behavior, which may lead to the greater dispersion of multiple SRM test results.

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Zhang, Zhen, Yong Chen, Guanbao Ye, Peilin Xiang, Yan Xiao, and Qiong Wang. "Empirical Method for Evaluating Resilient Modulus of Saturated Silty Clay under Cyclic Loading." Advances in Civil Engineering 2020 (October 21, 2020): 1–12. http://dx.doi.org/10.1155/2020/8846895.

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Resilient modulus of soil is crucial for the design of a structure on a foundation subjected to a cyclic loading (e.g., traffic load or machine vibration load). This paper conducted a series of dynamic triaxial tests of saturated silty clay, considering the influence of the factors of cyclic stress ratio (CSR), static deviatoric stress ratio (SDR), and overconsolidation ratio (OCR) on the resilient modulus and dynamic damping ratio of the soil. A cyclic loading with a form of half sine wave was used to model the traffic loading. The results showed that the soil was prone to failure under a higher SDR, even though the applied CSR was less than the critical CSR. The saturated silty clay performed a strain softening behavior and its dynamic properties deteriorated significantly when higher CSR and SDR and lower OCR were involved. Based on the test results, an empirical method with a form of exponential function was proposed to evaluate the resilient modulus of the soil, considering the combined effects of CSR and SDR and OCR. The proposed method was verified through a comparison with the test results in this study and from literatures, and some recommendations for its application were offered.

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Zhang, Cai Li, Ning Li Li, Qing Yi Xiao, Chuang Du, and Ti Song. "Study on Shear Performance and Construction Technology of the Stress Absorbing Layer in Underground Road Composite Pavement." Advanced Materials Research 671-674 (March 2013): 1189–92. http://dx.doi.org/10.4028/www.scientific.net/amr.671-674.1189.

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In this paper, a composite pavement stress absorbing layer is researched. Through the creation of the finite element analysis model of the composite pavement, the paper analyzed the shear stress and influencing factors such as a different level of force, the contact between the different layer, shear stress conditions, the surface layer modulus and thickness, base thickness, soil base resilient modulus. At last, the optimum thickness of the composite pavement structure layers is put forward.

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Lee, Jung-Yoon, and Jong-Mun Kim. "Deflection of Resilient Materials for Reduction of Floor Impact Sound." Scientific World Journal 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/612608.

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Recently, many residents living in apartment buildings in Korea have been bothered by noise coming from the houses above. In order to reduce noise pollution, communities are increasingly imposing bylaws, including the limitation of floor impact sound, minimum thickness of floors, and floor soundproofing solutions. This research effort focused specifically on the deflection of resilient materials in the floor sound insulation systems of apartment houses. The experimental program involved conducting twenty-seven material tests and ten sound insulation floating concrete floor specimens. Two main parameters were considered in the experimental investigation: the seven types of resilient materials and the location of the loading point. The structural behavior of sound insulation floor floating was predicted using the Winkler method. The experimental and analytical results indicated that the cracking strength of the floating concrete floor significantly increased with increasing the tangent modulus of resilient material. The deflection of the floating concrete floor loaded at the side of the specimen was much greater than that of the floating concrete floor loaded at the center of the specimen. The Winkler model considering the effect of modulus of resilient materials was able to accurately predict the cracking strength of the floating concrete floor.

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Hasan, Md Mehedi, Md Amanul Hasan, and Rafiqul A. Tarefder. "Development of Resilient Modulus Prediction Model for Granular and Noncohesive Soils of New Mexico." Advances in Civil Engineering Materials 8, no. 1 (July 12, 2019): 20180143. http://dx.doi.org/10.1520/acem20180143.

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Journal articles on the topic 'Resilient modulus model'

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