MAKING THE EARTH MOVE: Part sculpture, part trellis a family of timber grid shell structures will help enliven the flat landscape of the former colliery site being transformed into the Earth Centre near Doncaster. One of the shells was tested last week with 100kg loads, and as expected, it flexed and moved, but passed with ease. The Earth Centre is one of the landmark Millennium projects, and its first phase will centre on three buildings devoted to the theme of Planet Earth. Landscaped areas will include a forest garden where the six timber sculptures are being built, the largest 12m by 6m by 3m high. Plants will be grown through and around them. And while people are not intended to clamber all over them, the load testing was clearly needed just in case. The oak lath grids are complicated to design but straightforward to build, said Buro Happold structural engineer James Rowe. The consultant has carried out the structural design, working with landscape architect Andrew Grant Associates. Carpenter Oak & Woodland is building the frames.