外压荷载实验办法有哪些？ What are the experimental methods for external pressure load of reinforced concrete drainage pipes ?
Concrete pipe professionals explain the following analysis:
I. The GB / T11836-2009 standard specifies the external pressure load, instruments and measuring tools, experimental methods, experimental procedures, results calculation and experimental reports of Class II reinforced concrete drainage pipes.
Second, external pressure load
The three-point experimental method is used to test the crack resistance and damage load of the pipe through the transmission of mechanical pressure.
3. One test piece is a whole pipe or a cylinder with a length of not less than 1m taken from the pipe body; the tube age period for natural maintenance is not less than 28 days; the tube age period for steam maintenance is not less than 14 days.
Fourth, the experimental process
1. Check the condition of the equipment. The experiment can only be performed when the equipment is not faulty.
2. Place the test piece on the lower support beam of the external pressure test machine so that the axis of the tube is parallel to the two hard wood beams. Then the upper support beam is placed on the pipe so that the upper and lower support beams are parallel to the axis of the pipe;
3. Start the oil pump of the external pressure test engine to bring the pressure plate into contact with the upper support beam and apply the load uniformly at a loading speed of no more than 5kN / m per minute;
4. The load is graded according to the loading speed of the crack load. The load of each stage is 20% of the crack load and the constant pressure is 1 minute. When the load is gradually increased to 80% of the crack load, observe whether there is a small or no crack width, and continue to load until the crack width reaches 0.2mm, and read the crack load value.
5. Continue to press the damage. If it is not damaged, continue to apply 10% of the damaged load to the damaged load. Constant pressure for 3min. Check the damage status. If it is not damaged, continue to load it to damage.
6, the pipe body has been damaged can not continue to bear the load when the load value is the damage load.
Application scope of reinforced concrete drainage pipe joints:
(1) The pipe is suitable for laying concrete.
(2) The pipe is suitable for the direct buried laying of non-motorized lanes such as sidewalks and green belts, and is also suitable for the concrete enveloped laying of motorized lanes where heavy-duty vehicles pass.
It is widely used for cable protection in the power system and communication system, and can also be used as a water pipeline.
1. Low price, simple structure and convenient construction.
2, good processing performance, the device allows corners.
3. The current carrying capacity is high, and the laying coefficient is 10% higher than that of PVC pipes.
4, the chemical properties are stable, not aging, and its strength is increased at any time.
5. Corrosion resistance and non-magnetization.
6. The inner wall is smooth and the roughness coefficient is 0.07.
Reinforced concrete anti-corrosion drainage pipe joints are made of sepiolite mineral fiber, vinylon and cement as the main raw materials. After being stirred and mixed with high multiples of water, they are continuously rolled by the pipe making machine under pressure.