| 摘要 |
<p>A structural module for building prefabricated arch tunnels, the module having two shoulders (3), and an arched calotte (4) resting on the shoulders (3) and having an I-shaped cross section; the calotte (4) has a curved top wall (24) and a curved bottom wall (25) connected integrally by a vertical central web (26), so as to define, in combination with a number of identical calottes (4) assembled to one another, a lightweight vault with smooth underside and topside surfaces.</p> |
