You can figure out the achievement requirements by right clicking on them, viewing the image, and reading the image title. And one of the achievements are tf_heavy_eat_sandwich 0.o Valve is going off the deep end :/
EDIT: nice convenient list via shack news:
1. Iron Kurtain - heavy_damage_taken
2. Party Loyalty - heavy_defend_medic.png
3. Division of Labor - heavy_assist_medic_large
4. Red Oktoberfest - heavy_earn_medic_domination
5. Show Trial - heavy_kill_taunt
6. Crime and Punishment - heavy_kill_flag_carriers
7. Class Struggle - heavy_kill_medic_pair
8. Soviet Block - heavy_block_invuln_heavy
9. Stalin the Kart - heavy_block_cart
10. Supreme Soviet - heavy_receive_uber_grind
11. Factory Worker - heavy_stand_near_dispenser
12. Soviet Union - heavy_assist_heavy_grind
13. 0wn The Means of Production - heavy_clear_stickybombs
14. Krazy Ivan - heavy_kill_underwater
15. Rasputin - heavy_take_multi_damage
16. Icing on the Cake - heavy_kill_dominated
17. Crock Block - heavy_survive_crocket
18. Kollectivization - heavy_assist_grind
19. Spyalectical Materialism - heavy_uncover_spies
20. Permanent Revolution - heavy_kill_while_spinup
21. Heavy Industry - heavy_fire_lots
22. Communist Mani-Fisto - heavy_kill_crit_punch
23. Redistribution of Health - heavy_heal_medkits
24. Rationing - heavy_kill_shotgun
25. Vanguard Party - heavy_first_to_cap
26. Pushkin the Kart - heavy_payload_cap_grind
27. Marxman - heavy_kill_midair_minigun
28. Gorky Parked - heavy_defend_control_point
29. Purge - heavy_kill_capping_enemies
30. Lenin a Hand - heavy_revenge_assist
31. Five Second Plan - heavy_teleport_fast_kill
32. Photostroika - heavy_freezecam_taunt
33. Konspicuous Konsumption - heavy_eat_sandwiches
34. Don't Touch Sandvich - heavy_kill_scouts
35. Borscht Belt - heavy_kill_heavies_gloves