| 摘要 |
An earthen structure for holding back a body of water has a sloped surface which is paved with an overlapping arrangement of strips constructed of castable material. Each strip is formed by conveying castable material from a mobile receiving hopper that is propelled adjacent to the base of the earthen structure. A bridge conveyor projects laterally from the receiving hopper over the slope. The bridge conveyor deposits the castable material onto the slope forwardly of a spreader device that is advanced longitudinally relative to the slope by a prime mover. A scraper blade of the spreader device is positioned at a preselected elevation by a forwardly projecting sidewall which is connected to the blade and slidable on a previously formed strip. The sidewall maintains the castable material in front of the blade, as the advancing blade spreads the material in a longitudinal strip of a preselected thickness and having a lateral edge extending a preselected lateral dimension outwardly from the sloped surface. The formed strip is compacted by a pair of vibrating rollers propelled in tandem relation behind the spreader device. The rollers have forming end portions that engage the lateral edge of the strip to round and compact the edge.
|
