Abstract: The assembled foundation for transmission line, which is composed of concrete laths and angle steel scaffolds, has been applied to practice. Due to the gap of laths, the bottom area of the foundation is not clearly defined when calculating the compressive load. Theoretical research on the ultimate bearing capacity of foundation indicates that soil arching effect exists between the adjacent slabs. The shallow soil under the slab of assembled foundation can be approximately equivalent to a rigid body, which resists the compressive load together with the slabs as a whole. The in-site experiments at different lath intervals testify that the difference of soil pressures under the laths and at the gap of laths is relatively large in the shallow soil. But the soil pressures are basically the same in the deep layer where the change of the lath interval has no significant impact on soil pressure. The difference value between soil pressure under the laths and that at the gap of laths is small in the position of 3times laths width. And the difference value can be neglected in the position 5 times laths width. The research result suggests that the whole area surrounded by the laths is preferable in the calculation of compressive load on the assembled foundation composed of concrete laths.

Key words: transmission line, assembled foundation, concrete lath, calculation of compressive load, in-site experiment