| 摘要 |
The structure is made from three beams (1, 2, 3) crossing each other. It also is secured by tension members connecting certain ends of the beams. The first two beams (1, 2) can pass respectively over and under the third beam (3) which crosses them, there being an acute angle between the first two beams. The third bean can be horizontal, while the other two beams slope upwards from ground level. The two ends (3a, 3c) of the third beam are connected by e.g. cables to the feet of the other beams. Another cable (1d, 2a) connects the bases of the first two beams, while two further cables (1c, 3a; 2c, 3b) connect the upper extremeites of the first two beams with the central zone of the third beam. |
