Abstract: The existing models for calculating shield muck volume exhibit a low accuracy. To address this issue, an novel shield muck volume calculation model—the irregular triangular prism model—s proposed. The model creates the enveloping lines of muck surface contour and cut the muck into n irregular triangular prisms along the enveloping lines. By calculating volume of each prism, the volume of muck can be obtained. The model fuses two adjacent frames of data to fill the missing muck information between the two frames of data, thus restoring the real contour of the muck more accurately. Finally, a muck volume measuring platform is constructed, and the sandstone, sandy soil, and stone are used as experimental samples to test the measuring accuracy of two models. The results show that: (1) Compare to cross-sectional integration model, the irregular triangular prism model exhibits 13% and 25% increase in data stability and accuracy, respectively. (2) The measuring accuracy of stone, sandstone, and sandy soil by irregular triangular prism model is improved by ±5.4%, ±3.8%, and ±1.8%, respectively.

Key words: special-shaped triangular prism model, muck volume measurement, over- , and under-excavation evaluation, shield