# Introduction

A brief description of the example.

*CONTROL_SHELL Hemispherical Load LS-DYNA Manual Section: *CONTROL_SHELL Example: Hemispherical Load Filename: control_shell.hemi-load.k Description: A spherical shell is subjected to outward point loads on the x-axis and inward point loads on the z-axis. Model: The 1/8 symmetry model of a sphere measures 10 inches in radius with a thickness of 0.04 inches. The model contains 48 shell elements. A force of one pound is applied in the positive x -direction to the node on the x -axis. A force of one pound is applied in the negative z-direction to the node on the y-axis. Input: The element formulation is the Hughes-Liu shell with four integration points through the thickness. Note: If B-T element formulation is used the solution would be incorrect. To fix it, the Belytschko-Tsay shell requires the Belytschko-Wang-Chiang warpage stiffness modification (*CONTRO L_SHELL). The concentrated loads are applied to two nodes (*DEFINE_CURVE, *LOAD_NODE_POINT). Results: The oscillation of the node on the z-axis shows a regular oscillatory behavior. Since there is no specified damping, oscillations would be expected. Reference: Belytschko, T., Wang and Chiang.