Construction method for combining composite foundations of rigid piles and soft-soil foundations of water-draining consolidation and reinforcement highways

Abstract

The invention relates to a highway-foundation construction method and particularly relates to a construction method for combining composite foundations of rigid piles and soft-soil foundations of water-draining consolidation and reinforcement highways. The construction method comprises the construction steps of paving a working cushion layer; adopting a bagged sand well as a vertical water-draining body, adopting vibratory tube sinking to lower the bagged sand well, carrying out vibratory tube pulling, and supplementing materials at an empty well section in the tube pulling process; driving rigid piles, carrying out vibratory tube pulling after filling up concrete into sleeves by a mode of vibratory tube sinking, wherein the tube pulling speed is less than 1.2m/minute, and the tubes cannot be inserted inversely in the process of vibratory tube pulling; and casting pile caps, and adopting an inverse excavation construction method to cast the pile caps in constructed working cushion layers or filled soil; and backfilling roadbeds, arranging a settlement plate on column tops and among columns, filling to the height of less than 5m and adopting a vibratory pressing machine for flattening. Compared with the construction method for composite foundations of pile supporting dikes and rigid piles, the construction method for combining the composite foundations of the rigid piles and the soft-soil foundations of the water-draining consolidation and reinforcement highways has the advantage that the cost can be respectively saved by 40% and 46%.

Description

technical field [0001] The invention relates to a construction method of a road foundation, in particular to a construction method of a rigid pile composite foundation combined with drainage and consolidation to strengthen the road soft soil foundation. Background technique [0002] In coastal areas of our country, the river network is densely covered, the traffic is developed, and there are many bridges and culverts in the expressway with high clearance, resulting in the height of embankments, especially those near bridges and culverts, usually exceeding five meters. Under the trend of shortening the allowable construction period and decreasing allowable post-construction settlement, the composite foundation of concrete piles (prestressed pipe piles, CFG piles and rigid piles) is gradually applied to the soft foundation treatment of expressways. In view of the disadvantages of high cost of concrete composite foundation, obvious soil squeezing effect, partial concrete compos...

AI Technical Summary

Problems solved by technology

Therefore, the soft soil roadbed will not affect the construction period, but if the soft soil roadbed is not disposed of, it will have a great impact on the quality of the project

The damage to the soft soil foundation is very large. If the soft soil roadbed is not properly disposed of, it will greatly affect the service life of the bottom layer of the road surface, which will bring danger to everyone's life and property.

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