Design description: Yes, function: traffic road, Design content: water supply system , sewage drainage system, wastewater drainage system, rainwater drainage system, design phase: construction drawing design, Number of sheets: Less than 10 sheets
The distance and elevation in this design drawing are in meters, and the pipe diameter is in millimeters. The pipeline laying shall be carried out in accordance with the relevant pipeline construction specifications in GB 50268-97, and the gate shaft construction shall be subject to the General Atlas of Water Supply and Drainage Standards S1 (S143, 17-5). 1、 Pipe This design adopts water supply UPVC pipe. 2、 Pipe trench excavation 1. The pipe bottom width of pipe trench excavation is the outer diameter of the pipe plus 0.8m. Generally, the slope gradient of the trench side is 1:0.25. The trench excavation depth and pipeline are designed according to the size of the profile. 2. After ditching and dumping, the distance between the soil and the edge of the trench shall not be less than 0.8m, and the stacking height shall not be higher than 1.5m. 3. The pipeline can be directly laid on the undisturbed original soil foundation. If the foundation is rock or gravel, fine soil or sand cushion with a thickness of 0.15-0.20m must be laid on it. 3、 Pipe laying 1. Before the pipe is laid in the trench, the collapse stones, ponding, oil stains, etc. in the trench shall be removed. 2. The dirt and impurities in the pipe must be removed before the pipe is laid. 3. Allowable deviation of pipeline installation: axis position 30mm, height difference ± 0.3m. 4、 Pipe trench backfilling 1. The backfilling shall be carried out as soon as possible after the installation and laying of pipes. The backfilling time should be at the time when the temperature is lowest in the day and night. The backfill soil should not contain gravel and other hard objects. 2. Pipe trench backfilling is generally carried out in two times (1). As the pipeline is laid, the two ribs of the pipeline should be backfilled with sand or qualified original soil. The height of the backfilling should be 0.1-0.15m at a time. After tamping, the second layer should be backfilled until the backfilling reaches at least 0.1m above the pipe top. During the backfilling process, the gap between the lower part of the pipeline and the bottom of the pipeline must be filled. No backfilling is allowed within 0.2m before and after the pipeline interface, In order to observe the pressure test accident. (2) Large area backfilling after the pipeline passes the pressure test should be carried out when the pipeline is full of water. The part above 0.5m above the pipe top can be backfilled with original soil and compacted. 3. Before the pipeline pressure test, the thickness of backfill above the pipe top shall not be less than 0.5m to prevent the pipeline system from moving during the pressure test. 5、 Pipeline pressure test 1. Slowly inject water into the pressure test pipeline and discharge the air in the pipeline. After the pipeline is filled with water, it shall be kept for at least 48h without pressure. 2. The design test pressure of the pipeline is 1MPa. After the water pressure rises to the test pressure, maintain the constant pressure for 10min, check the interface and pipe body for damage and water leakage, and when the pressure drop is not more than 0.05MPa, the pipeline strength test is qualified.
