Issue 41

Y. Yang et alii, Frattura ed Integrità Strutturale, 41 (2017) 339-349; DOI: 10.3221/IGF-ESIS.41.45 348 (2) The tensile, compression and flexural moduli of the cement stabilized macadam increase with the increase of the loading rate, showing a power function growth pattern. (3) The tensile and compression moduli of cement stabilized macadam are significantly different. If only the compression modulus is used as the structural design parameter of asphalt pavement, there will be unbalance between the working state of the structural design parameter and the actual stress state, and further resulting in large deviation in load response analysis and affecting the safety of the design results. In order to improve the accuracy of the design calculation, we should select the corresponding design parameters according to the stress state of the points inside the pavement structure. (4) This paper reveals the differences between the tensile, compression and flexural moduli of cement stabilized macadam and their conversion relations, but it does not consider the impacts of different mineral aggregate gradations, which, however, are rather significant on the moduli of cement stabilized macadam. In order to improve the resistance of the semi-rigid base material against load damages, the gradation optimization will be one of the focuses in our future research. R EFERENCES [1] Sha, Q.L., The Design and Construction of Long Life Semi-Rigid Pavement for Heavy Traffic with Heavy Wheel- Load, Beijing: China Communications Press, (2011). [2] Sha, A.M., Material Characteristics of Semi-Rigid Base, China Journal of Highway & Transport, 1 (2008) 21. [3] Yao, Z.K., Asphalt Pavement Structure Design, Beijing: China Communications Press, (2011). [4] JTG D50-2006, Specifications for Design of Highway Asphalt Pavement [S]. [5] Wu, X., Zhao, H.J., Huang, Z.G., Yang, L.J., Thermal Bending and Buckling Calculations Bimodulous Plate, Journal of Chang’ an University (Natural Science Edition), 34(6) (2014) 117-124. [6] Patel, B.P., Khan, K., Nath, Y.A., New Constitutive Model for Bimodular Laminated Structures: Application to Free Vibrations of Conical/Cylindrical Panels, Composite Structures, 110(1) (2014) 183-191. [7] Luo, Z.Y., Xia, J.Z., Gong, X.N., Unified Solution for Expansion of Cylindrical Cavity in Strain-Softening Materials with Different Elastic Moduli in Tension and Compression, Engineering Mechanics, 25(9) (2008) 79-92. [8] He, X.T., Chen, S.L., Elasticity Solution of Simple Beams with Different Modulus under Uniformly Distributed Load, Engineering Mechanics, 24(10) (2007) 51-56. [9] Kong, J., Yuan J.Y., Pan, X.M., Elasto-Plastic Analysis of Thick Spheric Shell with Different Elastic Moduli for Tensile and Compressive Deformations, Mechanics in Engineering, 32 (1) (2010) 41-45. [10] Wu, X.., Yang, L.L., Huang C., Sun. J., Large deflection Bending Calculation and Analysis of Bimodulous Rectangular Plate, Engineering Mechanics, 27(1) (2010) 17-22. [11] He, X.T., Chen, S.L., Sun, J.Y., Applying the equivalent Section Method to Solve Beam Subjected Lateral Force and Bending-Compression Column with Different Moduli, International Journal of Mechanical Sciences, 49 (2007) 919- 924. [12] Zhang, Q.S., Zheng, J.L., The Double Moduli Calculation Method of Rigid Pavements, Journal of Changsha Communications Institute, 8(3) (1992) 40-47. [13] Liu, J.L., Ying, R.H., The Application Research of Double Modulus Theory in Flexible Pavement Design, Hunan Communication Science and Technology, 1(27) (2001) 16-23. [14] JTG E51-2009, Test Methods of Materials Stabilized with Inorganic Binders for Highway Engineering [S]. [15] Wang, Z.Z., Zhu J.Z., Chen, L., Guo, J.L., Tan, D.Y., Mi, W.J., The Stress Calculation Method for Deep Beams with the Shear-Bending Coupling Distortion under Concentrated Load, Engineering Mechanics, 25(4) (2008) 115-119. [16] Wang, D.R., Hu S.S., Influence of Aggregate on the Compression Properties of Concrete under Impact, Journal of Experimental Mechanics, 17(1) (2002) 23-27. [17] Zheng, J.L., New Structure Design of Durable Asphalt Pavement Based on Life Increment, China Journal of Highway and Transport, 27(1) (2014) 1-7. [18] Zheng, J.L., Lv S.T., Nonlinear Fatigue Damage Model for Asphalt Mixtures, China Journal of Highway and Transport, 22(5) (2009) 21-28. [19] Lv S.T., Fatigue Equation of Asphalt Mixture Considering the Influence of Loading Rate, Engineering Mechanics, 29(8) (2012) 276-281. [20] Mannan, U.A., Islam, M.R., Tarefder, R.A., Effects of Recycled Asphalt Pavements on the Fatigue Life of Asphalt under Different Strain Levels and Loading Frequencies, International Journal of Fatigue, 78 (2015) 72–80.