CN1059444A

CN1059444A - A kind of soil improving method by using blind drains for sprinkling irrigation

Info

Publication number: CN1059444A
Application number: CN89108061A
Authority: CN
Inventors: 孙长海
Original assignee: CHEMICAL PLANT OF TIANJIN PETROCHEMICAL CORP
Current assignee: CHEMICAL PLANT OF TIANJIN PETROCHEMICAL CORP
Priority date: 1989-11-02
Filing date: 1989-11-02
Publication date: 1992-03-18

Abstract

The present invention relates to the method on a kind of transformation salinity ground.It is that a trickle french drain is set on the certain depth of soil layer, the trickle french drain bottom surface certain thickness rubble of place mat, coarse sand, fine sand, the french drain upper strata surface water that contains salt successively can import gully by the trickle french drain, and the brackish water of gully regularly discharges the elsewhere.The trickle french drain can be shapes such as netted, crosswise or ring-type in the distribution on ground.Use this technology governance saline land to have tangible regulation effect, the salt content of soil layer can reduce year by year, can make the saline land become the good farmland.

Description

A kind of soil improving method by using blind drains for sprinkling irrigation

The present invention relates to the method that a kind of soil removes salt transformation salinity ground.

The method of saline-alkali soil improvement is existing multiple at present.A kind of is the method for open drain irrigation and drainage washing soil, but this method needs the fresh water amount big, and implementing the method under the situation of present northern China fresh water anxiety has certain difficulty.Another kind method is to adopt the method for plastic hidden pipe (or cement hidden pipe) draining desalination (the heavy saline improvement technology in state city is grown in Shandong, sees Science and Technology Daily on February 18th, 89).It is the trench that digs a certain depth on saline and alkaline ground, place mat one deck cement is to support the pipe of cement (or plastic tube) on it on the bottom surface of trench, the tube wall of pipe of cement has many permeable apertures, the water that contains certain salt that layer of ground soil was drenched enters pipeline by aperture, flow into gully by pipeline, again the salt water in the gully is drained.In order to prevent that earth from stopping up permeable aperture, also must be in the rubble and the fine sand (see figure 1) of place mat certain particle size around the pipeline.The weak point of this method is that pipeline easily stops up, and need clear up pipeline through certain hour, and workload is big, and is cumbersome, and whole construction costs is also higher.

It is low to the objective of the invention is to design a kind of construction costs, does not need to lay the french drain of concrete duct (or plastic conduit), to reach the effect of trickle desalination.

The designed french drain of the present invention is at the certain depth on saline and alkaline stratum rubble, coarse sand, the fine sand of place mat certain particle size successively, place mat soil layer on fine sand.There is one 2～4 inclination angle of spending the french drain bottom surface by certain orientation, and an end lower in the french drain bottom surface is provided with gully, and the water in the french drain rubble crack can flow to the gully of low end along the french drain ramped bottom surface.The saline land bigger for area can be provided with mesh blind ditch, crosswise french drain or annular french drain, and distance can be 3-10 rice (as Fig. 2) between ditch and the ditch.Surface water drenches a part of salt by soil layer and flows into french drain and flow to gully by french drain, and the salt water of gully regularly discharges the elsewhere.

Trickle blind ditch construction method can be illustrated by accompanying drawing 3 and embodiment.

On the saline land, dug wide * be the open drain of 70 centimetres of 100 cm x deeply, again open drain central authorities dig out one wide * be the trickle ditch of 30 cm x (30～40) centimetre deeply, the bottom surface compacting of ditch also has 2～4 inclinations angle of spending, and the low end in trickle ditch bottom surface digs a gully.The bottom surface of trickle ditch is the rubble of shop 15～20 cm thicks earlier, and the rubble granularity can be chicken dawn size.The coarse sand of place mat 5～10 cm thicks on rubble repaves the pad fine sand, and the trickle ditch is filled and led up on the coarse sand again.With faintly acid or neutral soil the big open drain on the trickle ditch is filled and led up then.The metalling of trickle ditch bottom plays lower floor's saline-alkali soil effect capillaceous of cutting off, and corrodes the soil layer on top to prevent subterranean water level from rising.The layer of sand on trickle ditch top mainly works to isolate levels, lets out the trickle bottom of trench under smoothly and imports in the gully in case soil runs off and makes the surface water on upper strata carry the part salt to the trickle ditch.Gully and trickle french drain joint have the spilled water hole of 10 centimetres of diameters, and outer cover one diameter in hole is 30 centimetres a drainage double-edged fine-toothed comb, and it is strong fixed in case the silt well to smear with cement around the double-edged fine-toothed comb.If the trickle french drain is near the river course, and french drain is higher than the river course normal water level, also can make the trickle french drain lead directly to river course, water channel, directly wash water entered the river course.

With trickle french drain technique improvement saline land, easy construction, investment is saved, and it is remarkable to remove the salt effect.Nineteen eighty-two begins to implement present technique in area, huge port, Tianjin improves the soil, and soil property improves year by year.The average salt content of nineteen eighty-two soil layer is 0.734%, and nineteen eighty-three reduces in December, 0.513%, 1988 and reduces to 0.06～0.15% again.

Description of drawings

The longitudinal and transverse profile of Fig. 1 hidden pipe

1, cement layer; 2, pipe of cement; 3, sand stone layer; 4, soil layer

Fig. 2 trickle french drain horizontal layout

1, cross is arranged 2, is circular layout

Fig. 3 trickle french drain is in length and breadth to profile

1, soil layer 2, fine sand layer 3, coarse sands layer 4, metalling 5, gully

Claims

A kind of soil improving method by using blind drains for sprinkling irrigation, it is characterized in that trickle french drain of excavation on the soil layer certain depth, the bottom of trench compacting also has 2～4 degree gradients, at the certain thickness rubble of bottom of trench place mat successively, coarse sand, fine sand, and then ditch is filled and led up with neutral soil or faintly acid soil, the lower end in trickle french drain bottom surface is provided with gully, and the trickle french drain can be shapes such as netted, crosswise or ring-type in the distribution on ground.