Knife and bulldozer bottom blade interaction with soil at the beginning of a pass

Introduction. At the beginning of the production of road construction works, it is necessary to remove stones, bushes, trees from the right-of-way of the future road. To perform such work, it is advisable to use cyclic units, in particular, with bulldozer equipment. Interaction with the soil of the knife and the blade of the bulldozer is accompanied by a complex of interrelated processes. These processes complicate the theoretical analysis of the interaction of the knife and the bottom part of the blade of bulldozer equipment with the soil. Therefore, despite the large number of publications, the interaction of the knife and the bottom part of the blade of bulldozer equipment with the soil is not analyzed in sufficient details. Meanwhile, without a detailed analysis of this interaction, it is difficult to modernize bulldozer equipment.
The method of research. Interaction with the soil of the knife and the blade of the bulldozer has two features. First, the knife of a bulldozer with a straight blade is installed perpendicular to the direction of movement of the unit, so the bulldozer knife carries out energy-intensive cutting of the soil. Secondly, the cut layer of soil moves the pile of the bulldozer in front of it. The concave shape of the surface of the working body causes a concave mapping of crumple stresses, leading to the appearance of a zone of volumetric compression of the soil, which increases more and more during the movement of the unit. Both the deviator and ball components of the stress tensor in the ground increase. Therefore, the front surface of the knife is divided into a blade and a plane that carries out, together with the plane of the lower part of the blade, the displacement of the primary displaced soil. It is necessary to consider separately the impact on the ground of the blade, the edge of the knife and the front surface of the knife and the lower part of the blade.
Results. From the drawings the length of the trace of the surface of the pseudo-displacement of the soil in the longitudinal-vertical section, the area of the primary ground shift with the edge of the knife, the area of impact on the ground of the knife surface, the area of impact on the ground of the surface of the lower part of the blade are determined. The area of pseudo-displacement of the soil and the area of displacement of the primary shifted soil were calculated. The dependencies of the areas on the recess of the bulldozer knife are constructed.
Conclusion. As the depth of the bulldozer knife increases, the area of pseudo-displacement of the soil by the surface of the knife, the area of primary ground shear with the right or left edge of the knife increases linearly. In this case, the displacement area of the primary shifted soil increases by the parabola. Identifying the area of the pseudo-displacement of the soil, the area of the primary ground shift with the right or left edge of the knife and the displacement area of the primary shifted soil will determine the energy costs required to affect the surface of the knife and the lower part of the blade on the ground.

1. Karasjov G. N. Opredelenie sily rezanija grunta s uchjotom uprugih deformacij pri razrushenii [Definition of the cutting force of soil considering elastic deformation at fracture]. Stroitel’nye i dorozhnye mashiny. 2008; 4: 36-42. (in Russ.)

2. Karnauhov A. I., Orlovskij S. N. Opredelenie zatrat udel’noj jenergii na process rezanija lesnyh pochv torcevymi frezami [Costing of specific energy on the cutting process of forest soils end mills]. Stroitel’nye i dorozhnye mashiny. 2010; 1:20-22. (in Russ.)

3. Kravec I. M. Opredelenie kriticheskoj glubiny rezanija pri kombinirovannom rezanii gruntov gidrofrezoj [Determine critical cutting depth when combined cutting soils gidrofrezoj]. Stroitel’nye i dorozhnye mashiny. 2010; 5: 47-49. (in Russ.)

4. Kirillov F. F. Determinirovannaja matematicheskaja model’ vremennogo raspredelenija tjagovogo usilija dlja mnogorezcovyh rabochih organov zemlerojnyh mashin [Deterministic mathematical model of the temporal distribution of traction for mnogorezcovyh working bodies of earthmoving machines] Stroitel’nye i dorozhnye mashiny. 2010; 11: 44-48. (in Russ.)

5. Berestov E. I. Vlijanie trenija grunta po poverhnosti nozha na soprotivlenie rezaniju [Influence of friction of soil on the surface of the knife cutting resistance]. Stroitel’nye i dorozhnye mashiny. 2010; 11: 34-38. (in Russ.)

6. Vershinin A. V., Zubov V. S., Tjul’nev A. M. Povyshenie jeffektivnosti diskofrezernyh rabochih mehanizmov dlja razrabotki mjorzlyh gruntov [Improving the efficiency of the working mechanisms for the development of diskofrezernyh mjorzlyh soil]. Stroitel’nye i dorozhnye mashiny. 2012; 8: 42-44. (in Russ.)

7. Balovnev V. I., Nguen Z. Sh. Opredelenie soprotivlenij pri razrabotke gruntov ryhlitelem po integral’nomu pokazatelju prochnosti [Identification of resistances when designing primers Ripper by a combined indicator of strength]. Stroitel’nye i dorozhnye mashiny. 2005; 3: 38-40. (in Russ.)

8. Ryabets N., Kurzhner F. Weakening of frozen soils by means of ultra-high frequency energy. Cold Regions Science and Technology. 2003; 36: 115-128.

9. Liu X., Liu P. Experimental research on the compressive fracture toughness of wing fracture of frozen soil. Cold Regions Science and Technology. 2011; 65: 421-428.

10. Talalay P. G. Subglacial till and Bedrock drilling. Cold Regions Science and Technology. 2013; 86: 142-166.

11. Sun X. ACT-timely experimental study on meso-scopic damage development of frozen soil under triaxial shearing. Rock and Soil Mechanics. 2005; 8: 150-163.

12. Li Q. Development of Frozen Soil Model. Advances in Earth Science. 2006; 12: 96-103.

13. Atkinson J. The Mechanics of Soils and Foundations. CRC. Press. 2007: 448.

14. Balovnev V. I., Danilov R. G., Ulitich O. Ju. Issledovanie upravljaemyh nozhevyh sistem zemlerojno-transportnyh mashin [Study of guided knife systems of ground-moving vehicles]. Stroitel’nye i dorozhnye mashiny. 2017; 2: 12-15. (in Russ.)

15. Nilov V. A., Fjodorov E. V. Razrabotka grunta skreperom v uslovijah svobodnogo rezanija [Ground development with a scraper in free cutting conditions]. Stroitel’nye i dorozhnye mashiny. 2016; 2: 7-10. (in Russ.)

16. Chmil’ V. P. Nasosno-akkumuljativnyj privod ryhlitelja s avtomaticheskim vyborom ugla rezanija. [Pump-accumulating ripper drive with automatic cutting angle selection]. Stroitel’nye i dorozhnye mashiny. 2016; 11: 18-20. (in Russ.)

17. Kabashev R. A., Turgumbaev S. J. Experimental research of the process of digging soil rotary-disk working bodies under hydrostatic pressure. The Russian Automobile and Highway Industry Journal. 2016;(4(50)):23-28. (In Russ.)

18. Semkin D. S. About influence of speed working bodies of digging machines on the resistance force of soil cutting. The Russian Automobile and Highway Industry Journal. 2017;(1(53)):37-43. (In Russ.) https:// doi.org/10.26518/2071-7296-2017-1(53)-37-43

19. Konstantinov Ju. V. Metodika raschjota soprotivlenija i momenta soprotivlenija rezaniju pochvy prjamym plastinchatym nozhom frezy [The method of calculating resistance and the moment of resistance to soil cutting with a straight plate cutter knife]. Traktory i sel’hozmashiny. 2019; 5: 31-39. (In Russ.)

20. Syromjatnikov Ju. N., Hramov I. S., Vojnash S. A. Gibkij jelement v sostave rabochih organov rotornoj pochvoobrabatyvajushhej ryhlitel’no-separirujushhej mashiny [Flexible element in the working organs of the rotary soil processing loosening and separating machine]. Traktory i sel’hozmashiny. 2018; 5: 32-39. (In Russ.)

21. Parhomenko G. G., Parhomenko S. G. Silovoj analiz mehanizmov peremeshhenija rabochih organov pochvoobrabatyvajushhih mashin po zadannoj traektorii [Power analysis of the mechanisms of movement of working bodies of soil processing machines on a given trajectory]. Traktory i sel’hozmashiny. 2018; 1: 47-54. (In Russ.)

22. Dranjaev S. B., Chatkin M. N., Korjavin S. M. Modelirovanie raboty vintovogo G-obraznogo nozha pochvoobrabatyvajushhej frezy [Simulation of the work of a screw G-shaped knife soil cutter]. Traktory i sel’hozmashiny. 2017; 7: 13-19. (In Russ.)

23. Nikolaev V. A. Mashiny dlja obrabotki pochvy. Teorija i raschjot [Soil processing machines. Theory and calculation]. 2014:358. (In Russ.)