The scientists conducted lab tests on jacked piles in clay soil to understand how they penetrate the ground. They found that the size and shape of the pile affect how much resistance it faces during jacking. As the pile goes deeper, the resistance on its sides increases. The length of the pile doesn't have a big impact on resistance. The data from the tests showed that the pile diameter and shape play a big role in how much resistance the pile encounters. The results help us understand how jacked piles work in cohesive soils and provide a basis for future lab tests.