Semi-filling and semi-excavating ecological subgrade structure and construction method

Abstract

The invention relates to a semi-filling and semi-excavating ecological subgrade structure. The semi-filling and semi-excavating ecological subgrade structure is characterized in that a junction face of a fill subgrade and an excavating subgrade is paved with waterproof geotextile and a step type integral connection net; a change fill layer, a pervious concrete isolation layer and waterproof geotextile are sequentially arranged at the bottom of the fill subgrade; through long transverse drainage ventilating pipes are arranged in the excavating subgrade and are communicated with a vertical ventilating channel close to a side slope; the fill subgrade is provided with a three-dimensional composite water drainage ventilation net which is in lap joint with the transverse drainage ventilating pipes; the side face of the fill subgrade is paved with waterproof geotextile and planting concrete; and side ditches are dug in the bottom of the side slope. According to the semi-filling and semi-excavating ecological subgrade structure, water in the subgrade can be effectively drained; underwater can be prevented from migrating to the subgrade and a road surface; frost heaving, thaw collapsing and frost boiling are effectively prevented; the defect that a longitudinal crack appears in a junction of the filling position and the excavating position of the subgrade due to uneven frost heaving can be effectively overcome; the good technical and economic benefits are achieved. The invention further discloses a construction method of the semi-filling and semi-excavating ecological subgrade structure.

Description

technical field [0001] The invention relates to a roadbed structure and a construction method, in particular to a half-filled and half-dug ecological roadbed structure and a construction method. It belongs to the field of highway engineering and is suitable for the construction of road subgrades in hilly areas or mountainous areas. Background technique [0002] Road projects in hilly or mountainous areas often require half-fill and half-dug construction. During excavation, the top surface of the subgrade is close to the groundwater level or the side slope of the cutting cuts off the aquifer or the subgrade presses down on the spring. When the drainage is not smooth, it is easy to cause road muddying. Road muddying is a physical and geological phenomenon of road frost damage. When the frost-heaved road is thawed in spring, the melted water in the middle and upper part of the roadbed is blocked by the unmelted frozen soil in the lower part, and cannot seep down, making the upp...

AI Technical Summary

Problems solved by technology

However, the patent has the following problems that cannot be solved: (1) The seepage water in the excavation part seeps to the filling roadbed as a whole, but the drainage and ventilation pipes are only arranged at intervals, so the seepage cannot be fully collected in the drainage and ventilation pipes, and the drainage effect is not ideal; (2) The filling In the square subgrade, only a layer of permeable isolation layer is set at the bottom of the subgrade for drainage. The drainage effect is difficult to guarantee when the water cannot seep down quickly, and further drainage measures are required; The transverse reinforcement is set, and the transverse reinforcement will cause local damage to the soil at the junction under the action of the road load

[0005] In summary, although the existing methods have achieved good results under suitable engineering conditions, there are still some areas to be improved.

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