Designed moisture and total moisture capacity of soils of the earthbed of motor roads

Introduction. The calculation of road pavements according to strength criteria is performed for the design period of the year, when the soil moisture reaches its highest values. Such moisture is called design moisture and is established by determining the highest value at a given one-sided confidence probability, taking into account various corrections for the terrain, roadbed design and shoulder reinforcement. It would seem that everything is done correctly, but in some cases, the design moisture reaches high values, within 80...90% of the moisture at the fluidity limit. Such values of design moisture are greater than the full moisture capacity of some types of soil. In this case, the physics of the soil water saturation process is violated.

Materials and methods. To calculate the total moisture capacity, the physical principles of engineering geology are used, based on a three-phase physical model of dispersed soil. In this model, each of the three phases (solid, liquid and gaseous) occupies a certain volume, and mineral particles and liquid have mass and weight. Based on this model, classical fundamental formulas are obtained that allow determining any physical characteristic of the soil. These fundamental dependencies are used to calculate the total moisture capacity. The calculation of the total moisture capacity is used when constructing a line of zero air content in the soil with its standard compaction. It is shown that the total moisture capacity depicted on this line is the highest moisture content for soil compacted to this state.

Results. A method for calculating the total moisture capacity of the soil at different compaction coefficients is proposed. Its value in winter is taken as the minimum possible compaction coefficient, calculated taking into account the correction of Yu.M. Vasiliev and A.S. Eremin, which takes into account soil decompression during water freezing. The total moisture capacity of the soil, calculated with a minimum compaction coefficient, is a limit value that the calculated humidity cannot exceed.

Conclusion. The authors’ ideas about the physical condition of soils are presented, according to which their calculated humidity cannot exceed the full moisture capacity at a given degree of compaction. Therefore, the value of the calculated humidity, expressed as a fraction of the humidity at the yield point Wр / WТ , is proposed to be limited to the relative value of the total moisture capacity Wsut / WТ .

1. Churilin V.S., at al. Regression models of irregular vertical displacement of a roadway cross section caused by frost heaving. Magazine of Civil Engineering. 2023; 120(4): 12009. DOI: 10.34910/MCE.120.9.

2. Churilin V.S., Efimenko S.V., Efimenko V.N., Sukhorukov A.V., Drozdov Yu.V. Estimated performance standardization of clayey soils in the Tomsk region for the quality assurance in road construction. Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel’nogo universiteta. JOURNAL of Construction and Architecture. 2020; 22(6): 177–187. (In Russ.) https://doi.org/10.31675/1607-1859-2020-22-6-177-187.

3. Matvienko O.V., Bazuev V.P., CHurilin V.S. Modelirovanie napryazhenij i deformacij dorozhnyh pokrytij. Dorogi i mosty. 2016; 36 (2): 139–153. (In Russ.)

4. Churilin V., Efimenko S., Matvienko O., Bazuev V. Simulation of stresses in asphalt-concrete pavement with frost heaving. Matec web of conferences. 2018; 216. 01011. DOI:10.1051/matecconf/201821601011.

5. Efimenko V.N., Efimenko V.N., Karimov E.M., Mamagakipova G.T. TMPA satellite model applied for determination of annual precipitations in road-building climatic zones in southwest Kyrgyzstan. Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel’nogo universiteta. JOURNAL of Construction and Architecture. 2021; 23(4): 147–158. (In Russ.) https://doi.org/10.31675/1607-1859-2021-23-4-147-158.

6. Efimenko V.N., Efimenko S.V., Bashirova I.A. Data bank for road-building climatic zones in Yamalo-Nenets Autonomous District. Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel’nogo universiteta. JOURNAL of Construction and Architecture. 2022; 24(6): 150–159. (In Russ.) https://doi.org/10.31675/1607-1859-2022-24-6-150-159.

7. Afinogenov O.P., SHalamanov V.A., Seryakova A.A. Obespechenie kachestva zemlyanogo polotna avtomobil’nyh dorog na osnove principov regional’nogo rajonirovaniya. Bulletin of the Kuzbass State Technical University. 2014; 103 (4): 106–110. (In Russ.)

8. Konorev A.S., Mironchuk S.A., Dumenko V.A., Aleksandrova A.I. Prognozirovanie perioda vesennego ottaivaniya grunta zemlyanogo polotna avtomobil’nyh dorog. Dorogi i Mosty. 2022; 48 (2): 43–58. (In Russ.)

9. Eremin R.A., Pudova N.G., Romanov D.B. Prostranstvennyj analiz georadarnyh dannyh. Dorogi i Mosty. 2023; 49 (1): 145 – 157. (In Russ.)

10. Eremin R.A., Kulizhnikov A.M. Opyt kompleksnyh obsledovanij dorozhnyh odezhd georadarami i ustanovkami udarnogo nagruzheniya. Dorogi i Mosty. 2021; 46 (2): 100 – 124. (In Russ.)

11. Kulizhnikov A.M., Eremin R.A., Pudova N.G., Zverev E.O. Metodicheskie podhody k obnaruzheniyu oslablennyh zon v dorozhnoj odezhde po dinamicheskim i kinematicheskim priznakam. Dorogi i Mosty. 2022; 48 (2): 82–97. (In Russ.)

12. Kiyalbaev A.K., Alimgazin B.T., Abdygapparov K. Primery opredeleniya raschyotnoj vlazhnosti grunta v tele zemlyanogo polotna v usloviyah zasushlivogo klimata. Vestnik Kyrgyzskogo gosudarstvennogo universiteta stroitel’stva, transporta i arhitektury im. N. Isanova. 2016; 52 (2): 31–38. (In Russ.)

13. Kiyalbaev A.K., Sagybekova A.O., YUn D.S. O raschyotnoj vlazhnosti grunta v rabochem sloe zemlyanogo polotna: primery rascheta. Dostizheniya nauki i obrazovaniya. 2018; 28 (6): 8–1. (In Russ.)

14. Craig R.F. Soil Mechanics. Seventh edition. Department of Civil Engineering, University of Dundee, UK. Published by Taylor & Francis e-Library, London and New York. 2004: 447 p.

15. Das B.M. Advanced soil mechanics. Third Edition. New York. Taylor & Francis. 2008: 567 p.

16. Aleksikov I.S., Kurdyukova L.E., Aleksikov S.V. Prognozirovanie fiziko-mekhanicheskih svojstv gruntov zemlyanogo polotna. Federal State Budgetary Educational Institution of Higher Education “Volgograd State Technical University”. 2008; 12: 51–53. (In Russ.)

17. Goryachev, M.G. Ocenka ozhidaemyh znachenij modulej uprugosti glinistyh gruntov pri stroitel’stve zemlyanogo polotna avtomobil’nyh dorog. Avtomobil’. Doroga. Infrastruktura. 2020; 2 (24): 1–14. (In Russ.)

18. Kalenova E.V., Goryachev M.G., Lugov S.V., YArkin S.V. Obespechenie trebuemoj prochnosti rabochej zony zemlyanogo polotna pri proektirovanii i stroitel’stve dorozhnyh odezhd. Advanced Science and Technology for Highways. 2021; 2 (96): 13–15. (In Russ.)

19. Ushakov V.V. Goryachev M.G., Kudryavcev A.N. Uchet prirodno-klimaticheskih uslovij ekspluatacii avtomobil’nyh dorog dlya proektirovaniya dorozhnyh odezhd. Vestnik Moskovskogo avtomobilno-dorozhnogo gosudarstvennogo tehnicheskogo universiteta (MADI). 2022; 3(70): 68–73. (In Russ.)

20. Aleksandrov A.S., Semenova T.V. Improvement of Mohr-Coulomb criterion for designing pavements of roads of low traffic intensity. The Russian Automobile and Highway Industry Journal. 2024; 21(5): 756–769. (In Russ.) https://doi.org/10.26518/2071-7296-2024-21-5-756-769.

21. Aleksandrov A.S. Three-parameter mohr– coulomb criterion with the bauschinger effect for calculation of road pavements. Structural mechanics and structures. 2023; 4 (39): 85–101. DOI: 10.36622/VSTU.2023.39.4.009. (In Russ.)