1. Introduction

With the developmentof computer technology, numerical modelling has become the third pillar of scientific research besides physical experiment and theoretical analysis. In the scientific literature on rock mechanics, papers involving numerical simulation account for more than 25% (data from Scopus^TM). Moreover,numerical modelling seems to be the only economically and technically feasible research tool to tackle these new era problems, e.g. deep earth mining and deepspace mining. There are many numerical methods for rock mechanics problems, for example, the discrete element model (DEM), discontinuous deformation analysis (DDA),Meshless Methods (MMs), etc. However, for rock mechanics problems, numerical modelling still has following shortcomings: challenges   in the selection of reliable parameters,uncontrollable human operation influences, unclear physical mechanism, lack ofextensive and solid verifications, etc. These shortcomings has hindered the further application of numerical modelling on rock mechanics and rockengineering to a certain extent.

International Numerical Modeling Contest of Rock Mechanics and Engineering(INCR) is proposed and organized by the Discontinuous Deformation Analysis Committee of International Society of Rock Mechanics and Engineering and the Discontinuous Deformation Analysis Committee of China Society of Rock Mechanics and Engineering. Its purpose is to encourage research students to conduct open, transparent and extensive verification of existing numerical methods and software on rock mechanics problems. INCR aims to providea platform for sharing experimental and numerical restuls on rock mechanics problems and promote the application of numerical simulation in rock mechanics and engineering. The 1^st INCR will be organized and sponsored byTianjin University, China University of Geosciences,Nanjing University and Hebei University of Technology.

2. Time arrangement

lRegistration Deadline: due at 3:00 p.m. 30^th July, 2021(Beijing time/UTC +8).

lContest Starts: 5:00 p.m. 20^th September, 2021 (Beijing time).

lContest Ends: 8:00 p.m. 24^th September, 2021 (Beijing time).

lResults Submission : 9:00 p.m. 24^th September, 2021 (Beijing time).

lContest Results: the results will be released on or before 30^th October, 2021.

lAwarding Ceremony: paper certificate will be issued.

3. Entry rules

o   Topics

o   Half-opened topic: there are two stages for the numerical modelling on classic rock mechanical problems, e.g. fracturing and granular flow. The first stage is called “white box stage”, in which a group of experimental data will be provided for the parameter calibration. After the calibration, the team is asked to simulate and predict the results under given conditions. The following stage is black box state The experimental data and reference numerical results of the black box stage will be released after the contest.

o   Teams

uTeam Members: The competition is open to all full-time/part-time graduate students. A team is allowed to have up to three students currently studying at the same university, and there are no restrictions on the school and departments of all participated stundets.

uTeam Leader: Any member in the team can act as the leader, and the leader will become the contact of the team.

o   Contest rules

l   Before the contest

uEach team can have one supervisor as a guide, and each student can only participate in one team.However,supervisor can provide supervision and guidance for multiple teams.

uThe team can download the paper template and contest sample task from the official website(http://www.dembox.org/en/col.jsp?id=110) in advancefor reference.

uAfter the begining of the competition, team leader should log on to the website to download the competition task.

l   During the contest

u   Each team should work on the task dependently. It is not allowed to seek help from others in any way. Team members can use "inanimate resources" such as webpages, books, articles, research reports, and databases, but the originality ofthe works submitted by the team must be declared. If there are any references,please indicate in the text to ensure that they do not infringe the intellectual property rights of others.

u   Commercial software or self-made numerical code or open source code can be used. Regardless of the method, reproducible supporting materials are required. (Commercial software includes but not limited to: Ansys, Abaqus, Comsol, Flac, PFC, Udec,3Dec, RFPA, MatDem, etc. The participating teams need to have the corresponding copyright license.)

u   Team membersare strictly prohibited from posting or sharing content in any form during the contest.

u   Each registered team, allowed to have up to three students, is required to complete the numerical modeling for a given half-opened task in three days (72 hours).

l   After the contest

u   The team consultant should name the final work of the team with "Team#Number"and submit it as an   attachment to the mailbox(INCR2021@126.com)before the deadline.

u   The submission form is a numerical modelling report and a result introduction video (within 5 minutes), which requires a complete presentation of the idea of the work,calculation principle, modeling process, results analysis, and innovation ofthe work, etc. The report should be submitted in the form of an Adobe PDF electronic file, up to 25 pages   in English, and its readable font must be at least 12 point font. The video formatcan be MPEG, AVI, MP4, etc.

u   Except for the team number, the submitted works shall not show any identifying information such as students, consultants or institutions.

Note: The Expert Committee reserves the right to disqualify teams that violate the rules of the competition or lower their reward levels.

4. Evaluation of works

o   Evaluation is blind, usually ends on the first weekend three weeks after the end of the contest.

o   All participating reposts are uniformly identifiedby a unique given number, which is called “Control Number”. Neither theauthor's name nor the university's name should appear in the report.

o   The judging panel has a presiding judge and several judges, and each entry report is independently judged and scored by two judges.If the difference between the two scores is too large, the two judges will be consulted to see if it is possible to reach an agreement for them. Iffailed, a third judge will be invovled for further evaluation, and a average score will be calculated based on the scores from the three judges. Finally, all the works will be ranked according to the score.

5. Award settings

The results of this contest are ranked in three categories: first prize, second prize and third prize. And the certificates will be issued.

6. Relevant institutions

l   Organizer/Sponsor

uDiscontinuous Deformation Analysis Committee of International Society of Rock Mechanics and Engineering,

uCommittee on Discontinuous Deformation Analysis of Rock and Soil Mass, Chinese Society of Rock Mechanics and Engineering,

uTianjin University

uChina University of Geosciences

uNanjing University

uHebei University of Technology

l   Technical support

         In order to ensure the smooth runing of the contest,the Expert Committee and Organizing Committee of the International Numerical Modelling Contest of Rock Mechanics and Engineering were set up to be responsible for the guidance, evaluation, organization and publicity of the contest.