README
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Dataset title: Load-displacement and fracture index data for unbound granular materials
By M.Kaan Etikan, Denis Jelagin, Manfred N. Partl and Erik Olsson

Recommended Citation:
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For complete metadata, including the dataset description, contact information and information about how to obtain the dataset. 
You can read the following journal articles to see obtaining and visualization in more detail:
	1. Etikan, M. K., Jelagin, D., Olsson, E., & Partl, M. N. (2024). Experimental and numerical analyses of crushing resistance of unbound road materials. 
	   International Journal of Pavement Engineering, 25(1), 2330630. https://doi.org/10.1080/10298436.2024.2330630 
	2. Etikan, M. K., Jelagin, D., Olsson, E., & Partl, M. N. (2025). A new statistical fracture model for particles in unbound road materials. 
	   Materials and Structures, 58(6), 228. https://doi.org/10.1617/s11527-025-02760-4 

Description:
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The data file contains experimental results for unbound granular materials (UGMs) with different gradations subjected to confined uniaxial monotonic compression tests,as reported in:
	1. Etikan, M. K., Jelagin, D., Olsson, E., & Partl, M. N. (2024). Experimental and numerical analyses of crushing resistance of unbound road materials. 
	   International Journal of Pavement Engineering, 25(1), 2330630. https://doi.org/10.1080/10298436.2024.2330630 
	2. Etikan, M. K., Jelagin, D., Olsson, E., & Partl, M. N. (2025). A new statistical fracture model for particles in unbound road materials. 
	   Materials and Structures, 58(6), 228. https://doi.org/10.1617/s11527-025-02760-4 
Detailed descriptions of the experimental setup, sample preparation, testing procedures, and measurement methods can be found in both referenced papers.
During these tests, the reaction force and the displacement of the loading head were recorded. 
In addition, the extent of aggregate fracture at specific loading magnitudes was determined during the tests using the Bg-Index. 
The dataset also includes load–displacement reaction results from DEM simulations without particle fracture.
Furthermore, the parameter “u_B”, used to evaluate aggregate fracture in UGMs under progressively increasing load, is provided and is defined as the difference between DEM and experimental results.

Licence:
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CC BY-NC 4.0

Dataset organisation:
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- READMe.txt
- Load displacement data of measurements and non fracture DEM.xlsx
- Retained weight of UGMs after compression and Bg-Index.xlsx

Datafile description:
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The dataset contains two excel files:

1. Load displacement data of measurements and non fracture DEM.xlsx

	- This file contains load–displacement data for UGMs composed of different aggreagte types with different gradations subjected to confined uniaxial monotonic compression tests.
	- It also includes “no-fracture” load–displacement data for the same materials obtained from DEM simulations under confined uniaxial monotonic compression.
	- The new parameter, “u_B”, is presented for each UGM aggregate type and gradation combination.
		- The parameter “u_B” is used to evaluate aggregate fracture in UGMs under progressively increasing load.
		- It is obtained by subtracting the measurement data from the DEM data.
		- The complete dataset is provided in a main sheet, as well as in separate sheets for each aggregate type and gradation combination of the UGM.
		- The u_B sheet contains the formulation used for its calculation; however, ...
		  the resulting values are also provided explicitly in numerical format in the corresponding sheets for each aggregate type and gradation.
	- The experimental data are presented as mean value of interpolated load-displacement values with respect to the force array.
	
	- The dataset is organized as follows:
		- Row 1: Aggregate type
		- Row 2: Gradation of aggregates [mm]
		- Row 3: Porosity of the unbound granular material [%]	
	- The measurement data are then presented in two columns beneath these rows:
		- Column 1: Reaction force of the loading head [kN]
		- Column 2: Displacement of the loading head [mm]
	- The file contains a total of fifteen sheets. 

2. Retained weight of UGMs after compression and Bg-Index.xlsx

	- This file contains, for UGMs of each aggregate type, the cumulative weight retained from the smallest to the largest sieve, as well as the mean porosity, mean weight, gradation adn Bg-Index information.
	- The cumulative weight retained from the smallest to the largest sieve is presented as percentages.
		- For example, in the Brick sheet, cells C10 and C11 have values of 1.34 and 0.76, respectively.
		- This means that 0.76% of the mean weight corresponds to the 0.0–2.0 mm sieve size, while (1.34% − 0.76%) = 0.58% corresponds to the 2.0–4.0 mm sieve size.
		- Since the values are cumulative, the percentage recorded for the 2.0–4.0 mm sieve size is 1.34%.

	- The dataset is organized as follows:
		- Row 1: Aggregate type
		- Row 2: Gradation of aggregates [mm]
		- Row 3: Porosity of the unbound granular material [%]	
		- Row 4: Mean weight [g]	
	- The measurement data are then presented in seven columns corresponding to the cumulative weight retained, ordered from the smallest to the largest sieve size (from bottom to top):
		- Column 1: Before compression [%]
		- Column 2-4: After compression at the smallest applied force [%]
		- Column 5-7: After compression at the largest applied force [%]
	- The file contains a total of four sheets.