A method and apparatus for applying a force, displacement, or both to specimens, components, or systems by using a remote variable load/deflection device. The method enables testing of materials under actual in-service conditions. A displaceable container with a heating or heating and cooling element inside is provided. As heat is applied to the element, it expands thermally and causes the container to displace and apply force to specimens, components, or systems. The load/displacement of the container is modified by heating or cooling the element material. The container may be attached to in-service specimens, components, or systems and used to study the material behavior during in-service operation.