How to cooperate with buried composite pipe and concrete encapsulation? Key points of construction cooperation

How to cooperate with buried composite pipe and concrete encapsulation? Key points of construction cooperation

The key to the combination of buried composite pipe and concrete encapsulation lies in the foundation treatment, the selection of backfill materials and pipeline protection measures. The coordination of the two construction needs to follow the specification requirements to ensure the long-term stable operation of the pipeline.

Foundation treatment is the first step to cooperate with the construction. The bottom of the pipe trench must be compacted, and the concrete cushion shall be laid on this basis, with a thickness of not less than 10cm. After the concrete cushion is hardened, a pure sand layer of about 5cm thick shall be laid on it to provide a uniform support surface for the pipeline. If the trench is located in rock, gravel or frozen soil, 200mm fine sand or soil shall be backfilled before laying the pipe.

Pipe laying requires strict slope control. The composite pipe shall be laid with a slope of not less than 1% towards the tank or sump to ensure that any leakage can be found at the lowest point of the leak. The pressure test must be carried out after the pipeline laying is completed, and the encapsulation construction can only be carried out after confirming that there is no leakage.

Trench backfilling is performed in layers. After the pipeline is installed, the trench shall be filled with fine sand, and the bottom of the trench shall be backfilled with fine soil or neutral sand with a thickness of 100mm. Then, the compaction operation can be carried out above the 150-200mm backfill layer on the upper part of the pipeline, and the direct contact surface of the pipeline is strictly prohibited. When backfilling the pipe trench, first backfill about 300mm thick river sand, and then lay cement concrete on it. The pipe trench also needs to be treated with anti-seepage treatment. The composite anti-seepage structure of 2.0mmHDPE membrane and anti-seepage concrete can be used to ensure that the equivalent clay anti-seepage layer meets the specification requirements.

For areas with poor soil quality, concrete encapsulation protection is required for pipelines. The pouring of encapsulated concrete needs to prevent the pipeline from floating up, and the pipeline can be fixed by outer frame fixture and sectional pouring to ensure the stable position of the pipeline. When the pipeline enters the manhole or building, the reinforced concrete foundation and enclosure shall be made not less than 2m long near the manhole or building side.