Simulate Soil Consolidation Simulate Soil Consolidation Due date 11:59PM Friday 28 May April 2021 (local Sydney time) You are tasked to write the parts needed for the simulation of soil consolidation....

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Simulate Soil Consolidation Simulate Soil Consolidation Due date 11:59PM Friday 28 May April 2021 (local Sydney time) You are tasked to write the parts needed for the simulation of soil consolidation. Changes to description This document is being updated: Students should refer to the Ed website for any clari�cations, or changes to being made to the assignment description. https://edstem.org/courses/5268/lessons/11409/edit/slides/82475 A brief list of changes is documented here. 9 May 2021 CLAY_COMPRESSIBILITY_RATE is 0.001. It is a constant de�ning water units moved per 1kN per hour (no longer 100kN) A message to all students about Academic Integrity This is an assignment and sta� are not permitted to give speci�c guidance on your code, or how to solve the speci�c problem. That is the purpose of the assessment that you are required to perform to achieve the grade. You may ask clari�cation questions about the assignment description. This is often necessary to implement functionality that is otherwise ambiguous. The assignment description is not intended to be complete and you can con�rm your assumptions in a form of a question. In asking the question you should be quoting the description you are asking about. If you have a question to ask on Ed please search before asking. However, remember that you should not be posting any assignment code publicly, as this would constitute academic dishonesty. Also, do not wait too long before starting. This assignment needs time and sustained e�ort. Background Consolidation is the gradual changes in volume of a partly or fully saturated soil when subject to a sustained load. The changes are mainly due to the removal of gases, �uids and organic matter from the soil. We simplify our model to consider this matter as water. A sample of soil shows the particles arranged with voids between them. Soil can be composed of many minerals, primary silica, but clay, sand, shale, rock. Some of these have more water content than others. Water is present within soil and we can assume water is an incompressible �uid, where any pressure applied will cause the water to move to a lower pressure. The water is e�ectively squeezed out of the soil very slowly. Soil consolidation has a huge impact on the planning and construction of buildings throughout history. The leaning tower of Pisa is a great example to showcase the importance of soil consolidation [https://www.geoengineer.org/education/web-class-projects/ce-179-geosystems-engineering- design/assignments/the-tilt-of-the-tower-of-pisa-why-and-how ]. https://www.youtube.com/watch?v=nK4oDD-4CeE The purpose of the simulation is to determine: how long consolidation will take for a given load and placement over a soil con�guration how much water is displaced during consolidation what are the changes in height of the soil after consolidation Simulation Input and Output functionality for �le input/output provided for you The simulation will require information about the nature of the soil, the load, and the parameters used to simulate. These are read from a �le using the three command line arguments. $ simulate.py

Your program will read in a �le for the simulation parameters from argument 1 Your program will read in a �le for the soil geometry and composition from argument 2 Your program will write to a �le for the results of the simulation from argument 3 For example: $ simulate.py tests/params_example1.in tests/soil_example1.in sim_results_p1_s1.txt Modelling of the problem The modelling of soil consolidation in this assignment makes the following assumptions: soil particles have no air soil particles initially have a capacity to hold water and is considered full for example, if clay can hold 40% water, then at the beginning of the simulation, the clay particle holds 40% water. water is an incompressible �uid water moving out of a particle will cause the particle to compress any amount of water removed from a particle cannot be reintroduced soil particle categorisation is limited to Clay and Shale and only relevant to the initial conditions bedrock is an incompressible particle and will always provide an equal and opposite reactive force The void particle is a simple characterisation of representing a lower pressure area and it is assume to have no volume or capacity. A sand column could be represented as a lower pressure region, but as a void it has no capacity. We model a particle of soil. soil consists of a mixture of solid matter (aggregate) and water. soil particle has a capacity to hold water. This is dictated by the soil type and the water capacity value [0,1] soil particle has pressure acting on it. Initially the soil particle is at a rest state, in equilibrium with its neighbours. adding force to the soil will cause change in pressure and result in a movement of water assume a particle is 1 unit wide and 1 unit deep (square) We model the movement of water. water is an incompressible �uid. the entire soil mass is considered as a body of �uid where the pressure is even throughout. water reaching a void in the soil will cause it to leak out (sink). Void are explicitly de�ned in every simulation. pressure acting on the soil will cause the equivalent water mass to leave the exit points of the soil. There should always be a leak point, place for water to be displaced. If soil has no leak points, the pressure will continue to rise and no water movement is possible until there is a break in those soil barriers such as bedrock. This building of pressure and breaking is not considered in the model or the simulation. water can move up into a void, against gravity. This is to reduce complexity of the assignment. We model the rate at which water moves out of soil: it is constant (for simplicity) Water volume moved per 1kN per hour CLAY_COMPRESSIBILITY_RATE = 0.001 SHALE_COMPRESSIBILITY_RATE = 0.0005 More water cannot be removed from a particle: if there is 0.04 water in a particle of clay, and 100kN is applied over one hour. Water moved is 100,000 x 0.001 = 0.1 . 0.1 > 0.04 , and we expect the particle of clay will have 0.00 units of water. File formats Applicable to parse_sim_parameters and parse_soil_data The �le format contains pairs of Labels and Values , as well as Comments . # comments label1 value(s) for label1 label2 value(s) for label2 label3 value(s) for label3 # comments ... Comments A comment is identi�ed when the # symbol �rst appears in the line after any whitespace. # a valid comment # also a valid comment ### valid comment -- # INVALID comment NOT # a # comment Comments can appear after or before a label/value(s) pair. # comment1 # more of comment1 label1 value(s) for label1 # comment2 # comment2 label2 value(s) for label2 # comment3 label3 value(s) for label3 # comment4 # more comments... Labels and Values A label is the text used to identify the parameter. e.g. Load weight . A value is information for that label. e.g. 1000 Load weight 1000 Once a label has been identi�ed, the value(s) are always in next lines that follow. A blank line is used to separate de�nitions of labels and their values. Labels can appear at any point within the �le. There is no speci�c ordering. Label matching and identi�cation Each �le format has a well de�ne set of labels. All label matching is case insensitive. Duplicate labels Labels appearing more than once are permitted, however, only the last value is used. For example: Load weight 1000 Load weight 800 During the reading of the �le, the program should print a message to the console stderr Warning label Load weight defined twice. Using last value of 800 Simulation Parameters �le format Applicable to parse_sim_parameters Load location, width , Load weight Load type Load timing Load custom data , , , ... Format details Load location, width 2 integers, representing columns starting and how many columns wide comma separated must each be positive integers from 0 to 100 Load weight 1 integer representing kilonewtons of weight must be a positive integer between 0 and 1,000,000 Load type 1 string - Constant or Linear or Custom Optional, default is Constant . Load timing 1 integer representing the number of hours the load will apply for Linear not used for Constant or Custom Load types must be a positive integer between 0 and 1,000,000 Load custom data pairs of integer values representing the weight of the load at the given time Comma separated in the order , Used when Custom Load type is de�ned. Otherwise ignored. Must have an even number of values (a whole number of pairs) de�nes zero and positive integers time values de�ned incrementally no duplicate time values Example �le Load location, width 0, 1 Load weight 100 Load type Linear Load timing 100 Load location, width 1, 3 Load weight 3860 Load type Linear Load timing 56 Load custom data 1,10, 25,50, 75,55, 4,100, 5,150 Soil data �le format Soil width, depth , Soil keys , , , , ... Soil data ... ... ... ... ... ... ... ... ... ... The keys describe a symbol to use for a particular soil category. The width of the symbol is 1 character. The key description is a string of any size Example Soil width, depth 30, 20 Soil keys C,Clay, H,Shale, B,Bedrock, V,Void Soil data CCCCCCCCCCCCCCCCCCCCCCCCCCCCCC CCCCCCCCCCCCCCCCCCCCCCCCCVCCCC HHHHHHHHHCCCCCHHHHHHHHHHHVHHHH HHHHHHHHHCCCCCHHHHHHHHHHHVHHHH HHHHHHHHHCCCCCHHHHHHHHHHHHHHHH HHHHHHHHHHHHBBBBBBBBHCCCCHHHHH HHCCCCCCHHHHHHHHHHHHHCCCCHHHHH HHHHHHHHHHHHHHCCCCHHHHHHHHHHHH HHCCCCCCCCCCCCCCCCCCCHHHHHHHHH HHHHHHVVHHHCCCCCCCCCCCCCCCCHHH HHHHHHHHHHHHHHHVVVHHHHHHHHVHHH HHCCCCCCCCCCCCCCCCCCCHHHHHVHHH HHHHHHHHHHHCCCCCCCCCCCCCCCCHHH HHHHHCCCCCCCHHHHHHHCCCCCCCCHHH CCCCCCCCCHHHHHCCCCHHHHHCCCCCCH HHHHHCCCCCCCHHHHHHHCCCCCCCCHHH CCCCCCCCCHHHHHCCCCHHHHHCCCCCCC HHCCCVVVCCCCCCCCCCCCCHHHHHHHHH CCCCCCCCCHHHHHCCCCHHHHHCCCCCCC BBBBBBBBBBBBBBBBBBBBBBBBBBBBBB A special particle is the void. Void is represented by a V . It represents a space which will allows water to move to (lower pressure). Format details Applicable to parse_soil_data Soil width, depth 2 integers representing the number of columns and the number of layers (rows) of soil data to follow comma separated must each be positive integers from 0 to 10,000 Soil keys pairs of character,string for representing a soil particle type by a single character comma separated must have an even number of values must de�ne single character followed by a string no duplicate values (key or description) Soil data string(s) must have the appropriate number of columns and rows previously de�ned must be characters de�ned in the Soil keys all rows are equal length all columns are equal length Simulation parameters