Insiders in greenhouse engineering said that greenhouses are also called greenhouses, such as glass greenhouses, plastic greenhouses, etc. The greenhouse structure should be sealed and heat-preserving, but it should also be easy to ventilate and cool. Modern greenhouse projects have equipment to control temperature, humidity, and light conditions, and use computers. Automatically control to create the best environmental conditions for plants. The following editor will introduce you to the eleven techniques of greenhouse construction!
1. Leveling the land and laying out the line: According to the designed plan of the solar greenhouse, the azimuth angle is measured by the plate, and the four corners of the greenhouse are determined, and piles are placed at the four corners of the greenhouse, and then the positions of the gable and the back wall are determined.
2. Building the wall: The soil used for building the earth wall can be the soil outside the rear wall of the greenhouse, or the soil below the cultivated surface in the front of the greenhouse. If you use the quiet soil in front of the greenhouse, you can dig out the plough layer (about 25 cm thick), put it aside, and water the raw soil at the bottom. After a day, dig the raw soil to make a soil wall. First, plywood according to the thickness of the soil wall, fill in the freshly excavated wet soil, and compact with earth tamping or electric tamping. Each layer is about 20 cm. After tamping one layer, make the second layer until it reaches the required height. The gable and the back wall must be made together, not in sections, only in this way can they be strong. If the viscosity of the soil is not enough, it can be mixed with wheat straw. In some areas, the soil viscosity is very low, and the wall cannot be built by tamping. At this time, a certain amount of wheat straw and mud can be mixed into the soil to make adobes. After the adobes are dry, the adobe walls can be used. When building walls, grass mud should be used between the adobes, and grass mud should be plastered on the inside and outside of the wall. During the construction of the brick wall, the foundation must be tamped before the wall can be built. During the construction, the mortar should be full, the brick joints should be hooked up, the plastered surface should be plastered, and the inside and outside of the wall should be plastered to avoid air leakage. The void between the brick wall layer and the layer should not be too large or too small. Generally, the width of the hollow is controlled between 5-8 cm. The hollow should not be left to the end, and bricks should be used to connect the layers every 3-4 meters to improve the firmness of the wall. The hollow wall can be filled with slag, perlite, or wheat straw, or nothing is added. Only air insulation is used. The hollow wall without filling must be free of cracks. When the brick roof is open, it is best to use mud chaff to seal the roof by 30 cm, so that the back wall and the back roof are closely connected, and the thermal insulation performance is improved.
3. Buried columns and roof trusses: According to the drawings, determine the position of each column and mark it with lime. Dig a hole 30-40 cm deep and use stone as the foot of the column to prevent the column from sinking. Then install the digger on the rear column. The head is placed on the column, and the tail is on the back wall or behind. Put 3-4 purlins on the pillars. The ridge purlins are connected in a straight line, and the other purlins are staggered. To prevent the purlin from sliding down, a small wooden block can be nailed to the purlin at the lower part of the purlin to jam the purlin. Some greenhouses only use uprights to support the spine purlins.
4. After covering the roof: cover the purlin or rafter with a layer of waste plastic film, and put the corn stalks in bundles on the film, the direction of which is perpendicular to the purlin or rafter. Then spread wheat straw or straw on the corn stalks, and then spread a layer of plastic film on the corn stalks, and spread the straw mud on it. The rear roof is composed of straw and wheat straw wrapped in two layers of plastic film to form a quilt-like covering. The thermal insulation performance is greatly improved than that of the ordinary rear roof without plastic film. After the rear roof is covered, use grass mud to wipe tightly the connection between the inner side of the rear roof and the rear wall of the greenhouse.
5. Dig cold-proof ditch: Dig a cold-proof ditch 20 cm wide and 40 cm deep in the front of the greenhouse.
6. Fixed lead wire for buried anchor and laminating line on the rear roof: Lay a piece of No. 8 lead wire equal in length to the greenhouse at the bottom of the cold-proof ditch, with ground anchors pierced on it. The ground anchors are made of iron rings at both ends. For the lead wire, tie a brick or wooden stick on the lead wire every 3 meters according to the distance between the arches to be buried, and place it between these fixed objects. On the outside of the rear wall of the greenhouse; dig trenches to bury the ground anchors in the same way, except that the distance between the ground anchors can be increased to 2-3 meters, and the soil can be filled firmly after being buried, and the upper ring of the iron anchor is exposed on the ground. On the back roof of the greenhouse, pull a piece of No. 8 lead wire, and bury both ends of it in the ground outside the gable of the greenhouse. When burying people, tie heavy objects on their heads. Fix the lead wire with lead wire or nylon rope, tie one end to the lead wire and the other to the iron anchor buried outside the back wall.
7. Roof before construction: Adjust the position of the vertical column before and after it is buried, so that the rows and columns of the vertical column are aligned, and the 4-meter-long bamboo slices should be tied together. The length should be appropriate. One end is inserted in the cold-proof ditch, and the lower part is cold-proof The south side of the ditch is pushed tightly with bricks, and the angle should be such that the arch is perpendicular to the ground or slightly inclined to the south when it is erected. Tie beams to the columns supporting the front roof. The beams are 20-30 cm away from the top of each row of columns. A small hanging gui is placed on the beams. The upper and lower ends of the small hanging columns must be perforated, and No. 8 lead wires are used to pass through the holes. , Bend the arch pole, one end of the small suspension column is tightly tied to the arch pole, and one end is supported on the beam and tied tightly. The upper end of the arch can be inserted on the ridge purlin. Then, keep adjusting the small hanging column to make the same height of the same position of the front roof.
8. Covering film: There are two or three sheets of film in the greenhouse. When two sheets are used, their widths are 3 meters and 5 meters respectively, and when three sheets are used, their widths are 2 meters, 4 meters, and 2 meters respectively. First, roll back one side of the 3m or 2m wide film, glue it with an adhesive or iron it into a 5-6cm wide tube, install a clay dragon rope, and fix the 3m wide film at a distance of 2.5m from the ground. It is fixed at a distance of 1.5 meters from the ground with a width of 2 meters. The film is first rolled into a roll, and filled with soil into the cold-proof ditch while covering and tightening. The nylon rope should be tightened, together with the film, buried underground in the gable of the greenhouse. One or two of the above films are also rolled into a roll, one end is buried in the ground against the gable, and then spread to the other end, and finally buried in the ground near the gable at the end. There are two ways to fix the end of the film near the back roof. One is to fix it directly on the spine purlin with bamboo and iron nails; the other is to fix it on the spine purlin with bamboo and iron nails and then fold it back. Buckle on the back roof. The width of the roof after the buckle is about 0.5-1 meters, the more the better, and the grass mud should be used to compact it. This method has a better effect of improving the thermal insulation performance for the rear roof without adding waste film.
9. Fixed laminating line: After the film is covered, it must be pressed and fixed with a laminating line. The laminating line can be a commercially available polypropylene greenhouse special laminating line, or it can be replaced by nylon rope or iron wire. No need. It is best to use a dedicated laminating line. First tie one end of the laminating line to the No. 8 lead wire on the rear roof of the greenhouse, throw it down from the greenhouse, and press it on the film between the two arches, and the anchor ring at the lower end, tighten and tie it. The order of fixing the laminating line is thin first, then dense, first fixing several laminating lines with a large distance, and then gradually fixing a laminating line between each arch. Both the laminating line and the plastic film have a certain degree of elasticity, and the laminating line must be fixed on the second and third days; tighten it for 2-3 times to ensure that it is firmly compressed, and the compressed front roof film is wavy shape.
10. Upper straw thatch and paper quilt: The paper is made of 4-6 layers of kraft paper. The straw thatch is made of straw or cattail. The width of the straw thatch is 1.2-1.3 meters and the width of the cattail thatch is 1.5-1.6 meters to cover the greenhouse. If there is no paper quilt, it can cover two layers of grass thatch or increase the overlap between the grass thatch. Each piece of grass thatch is twice or slightly longer than the length of the grass thatch. The nylon rope is pulled and placed, and the two ends of each rope are respectively fixed to a side of one end of the grass thatch, forming two loops to entrap the grass thatch. Pull the two ropes on the surface of the grass thatch to roll up or unfold the grass thatch on the front roof of the greenhouse. The rolled grass thatch is staggered or placed one after the other on the back roof. In order to prevent the grass thatch from sliding down, one stone or two or three bricks can be blocked behind each roll of thatch.
11. Treatment of migrants: The solar greenhouse can keep the door at the east gable wall of the greenhouse. The door should be as small as possible. An insulation room should be built outside the door. Curtains should be hung on the inside and outside of the door, generally not on the west gable or back wall of the greenhouse. Stay at the door.