Tab 04 4 Statement of Work

Statement of Work
BP-1 Lunar Regolith Simulant Material Testing

1. Introduction / Background / Need

NASA is developing LS-DYNA simulations of the Human Landing System (HLS) touchdown on the surface of the Moon. The objectives of the simulations include predicting the HLS lander dynamics, with an emphasis on determining the depth to which the lander footpads penetrate the lunar soil (i.e., regolith). The predictive capability of the LS-DYNA simulations relies on accurately representing the lunar regolith mechanical properties such as strength, stiffness, and compressibility. The regolith material characteristics have been determined to be a driving parameter influencing the lander dynamics; however, very little regolith material data is available to anchor the parameters used in the LS-DYNA material models.
The tests described in this Statement of Work are intended to provide material data for the lunar regolith LS-DYNA material models. NASA's HLS landings simulations use the LS-DYNA MAT016 Pseudo-Tensor and EOS8 Tabulated Compaction material models. The MAT016 model defines the material properties and requires input parameters based off of shear strength, cohesion and friction angles. The purpose of the tests described herein is to produce the parameters necessary to develop six MAT016 models representing different initial densities of lunar regolith. In addition to the material parameters, information on the theoretical minimum and maximum void ratios in the material is sought. Since actual regolith from the lunar surface is not available, the tests will be conducted using a regolith simulant called BP-1.

2. Scope of Work

The Contractor shall conduct the following tests and data processing to support NASA's development of the regolith LS-DYNA material models. The BP-1 regolith simulant required for the tests has been provided by NASA in bulk form. 7) Materials.Testing.
a. Conduct minimum void ratio and maximum void ratio test of BP-1 regolith simulant in accordance with the procedures set forth in ASTM D4254 (maximum) and ASTM D4253 (minimum).
b. Conduct direct shear tests with a minimum of 3 normal forces with BP-1 simulant representing six representative densities specified in Table 1. NASA and the vendor shall agree on the densities to be used for the testing.

Table 1. Targeted density for material property measurements Sample Density (kg/m 3)
1.500
1.560
1.600
1.700
1.735
1.800

c. Conduct a minimum of one hydrostatic compression test with BP-1 simulant