Exercise 2.4 - Sandpile

Examination of granular material flow:


In this laboratory work,  we will study the mass fluctuations of a sandpile grown on different circular plates. The work consists of two parts. In the experimental part we will consider the shape of the sandpile grown by sand deposition and the avalanches (outflow, and its fluctuations). The computational part is done simulating a sandpile by a simple cell automation.

Schedule and appointments

Register to the exercise here: https://mycourses.aalto.fi/mod/choicegroup/view.php?id=699788

The registration must be made before 31.3.2021. Maximum of 15 students will be accepted. Ask for the model data from the assistant, when you want to start preparing the report, but not later than 31.3.2021.

NOTE: The reports should be submitted in English.


The course will be fully online. The model data for this work will be provided to students.

Prerequisites for the exercise:

Please, read the instructions below thoroughly beforehand. You should also be ready to answer the following questions:
1) What is a phase transition in mechanics?
2) What is a critical point?
3) What is self-organized criticality and how it is connected to sandpile experiment?
4) What other examples of self-organized criticality can you mention?

Report submission and grading:

After receiving the model data the students will have three weeks to return the first version of their report. Teaching assistant will grade the first version and give a feedback to the student, after which the student can improve (in two weeks time) the report, which will be evaluated again. The final grade is the average grade of the first and second version of the report.

Reading material

1) P. Bak, C. Tang, K. Wiesenfeld, Phys. Rev. Lett. 59, 381-384 (1987)

2) P. Bak, C. Tang, K. Wiesenfeld, Phys. Rev. A 38, 364-375 (1988)

3) N. Yoshioka, Earth Planets Space 55, 283-289 (2003)

4) S. R. Nagel, Rev. Mod. Phys. 64, 321-325 (1992)

Contact information