CN114775353A

CN114775353A - Environment-friendly roadbed treatment method based on sponge city

Info

Publication number: CN114775353A
Application number: CN202210031748.2A
Authority: CN
Inventors: 阙梦辉; 黄松峰; 徐林涛; 曾祥玉
Original assignee: Central and Southern China Municipal Engineering Design and Research Institute Co Ltd
Current assignee: Central and Southern China Municipal Engineering Design and Research Institute Co Ltd
Priority date: 2022-01-12
Filing date: 2022-01-12
Publication date: 2022-07-22

Abstract

The invention provides an environment-friendly roadbed processing method based on a sponge city, which comprises the following steps: presetting a pile foundation on a pretreated foundation, and then driving a pile barrel into the pile foundation, so that water flow is intensively discharged to a municipal pipe network after penetrating into the pile barrel; the pile tube is composed of an outer layer made of geotextile with a closed bottom and an open top and filling discrete materials coated in the geotextile. The advantages are that: the problem of under the traditional construction mode, rely on facilities such as pipe canal, pump station to concentrate the restriction of drainage, solve the restriction of the drainage of general surface soil layer retaining, full play underground water storage function adjusts city weather, constructs the sponge city.

Description

Environment-friendly roadbed treatment method based on sponge city

Technical Field

The invention relates to the technical field of road traffic construction, in particular to an environment-friendly roadbed processing method based on a sponge city.

Background

The sponge city, namely the city, can be like a sponge, has good elasticity in the aspects of adapting to environmental changes and coping with environmental changes, absorbs, stores, seeps water and purifies water in rainy days, and releases and utilizes the stored water when needed. The sponge city is a sustainable city construction idea, so that modern cities have the capacities of disaster prevention and reduction and ecological function maintenance for coping with climate change and extreme rainfall. The existing rainwater treatment mode related to sponge city mainly comprises: the developed municipal pipe network drainage system, establish the cistern to the water storage treatment and recycle, regional inner water circulation (lay permeable brick, formula greenery patches that sink, rainwater flower bed etc.) etc. some present rainwater processing methods belong to the drainage of impoundment of surface layer basically, can not effectually hold back the rainwater when meeting the rainfall flood calamity, even establish developed municipal drainage system, nevertheless belong to thick emission, do not accord with the connotation in sponge city completely.

Disclosure of Invention

The invention provides an environment-friendly roadbed treatment method based on a sponge city, which solves a plurality of problems of urban waterlogging, rainwater resource utilization and the like through water seepage, water storage and drainage.

In order to achieve the above object, the present invention provides the following technical solutions:

the environment-friendly roadbed processing method based on the sponge city comprises the following steps: presetting a pile foundation on a pretreated foundation, and then driving a pile barrel into the pile foundation, so that water flow is intensively discharged to a municipal pipe network after penetrating into the pile barrel;

the pile tube is composed of an outer layer made of geotextile with a closed bottom and an open top and filling discrete materials coated in the geotextile.

Preferably, the filler dispersion material is one or a mixture of more of crushed stone, steel slag or slag.

Preferably, the specific steps are as follows:

s1, road surface layer treatment: the part above the top surface of the foundation is sequentially provided with a gravel cushion layer, a compact base layer, a waterproof sealing layer, a permeable base layer and an asphalt permeable layer from bottom to top to form a pavement structure, and the permeable base layer and the asphalt permeable layer are respectively provided with a cross slope for guiding rainwater seepage of a pavement;

s2, pile construction: constructing a pile foundation on the edge of the cross slope, and driving a pile barrel into the pile foundation to ensure that water in the cross slope is gathered and then permeates into the pile barrel;

s3, arranging a water collecting chamber: a water collecting chamber is arranged on one side, far away from the cross slope, of the pile barrel, the water collecting chamber is arranged at 1/4-1/3 positions of the upper portion of the pile barrel and connected with the pile barrel, and a water drainage hole is formed in the water collecting chamber and used for collecting water in the pile barrel to the water collecting chamber and then draining the water to a municipal pipe network through the water drainage hole;

and S4, paving sand and stone cushions above the pile barrel, the roadbed and the water collecting chamber, and leveling to form a W-shaped drainage mode.

Preferably, in step S1, the slope of the cross slope is 0.5% to 2%.

Preferably, in step S2, the clear distance between the pile casing and the driving road surface is less than or equal to 50 cm.

Preferably, the specific steps are as follows:

s1, pile construction: constructing a pile foundation at a roadbed with a structure, and driving a pile barrel into the pile foundation;

s2, road surface layer treatment: the part above the top surface of the pile cylinder is sequentially provided with a gravel cushion layer, a permeable geotextile, a permeable base layer and an asphalt permeable layer from bottom to top to form a pavement structure, the middle of the pavement is a structure, and the periphery of the structure is provided with a waterproof sealing layer; water flows on two sides of the structure sequentially pass through the asphalt permeable layer, the permeable base layer, the permeable geotextile and the sand cushion layer and then enter the pile barrel to form a V-shaped water seepage channel from top to bottom and then are discharged to the municipal pipe network.

Preferably, the specific steps are as follows:

s1, pile construction: constructing a pile foundation at the roadbed, and driving a pile barrel into the pile foundation;

s2, road surface layer treatment: the part above the pile cylinder top surface is sequentially provided with a gravel cushion layer, a permeable geotextile, a permeable base layer and an asphalt permeable layer from bottom to top to form a pavement structure, and the pavement water flow direction is formed from top to bottom and is discharged to a municipal pipe network in a full-penetration drainage mode.

The invention relates to an environment-friendly roadbed processing method based on a sponge city, which has the advantages that:

1. the treatment method solves the problem of the limit of centralized drainage by means of facilities such as pipe ducts, pump stations and the like in the traditional construction mode, solves the problem of the limit of water storage and drainage of common surface soil layers, fully exerts the underground water storage function, regulates the city climate and builds sponge cities;

2. the geotechnical cloth which has transverse restraint force, pulling resistance, acid and alkali resistance, corrosion resistance and the like and can be used stably for a long time is wrapped around the gravel pile, so that higher bearing capacity is provided compared with the original gravel pile, the consumption of gravel materials is controllable due to the transverse restraint of the geotechnical cloth, and the gravel materials can be replaced by waste materials such as slag, steel slag and the like, so that the geotechnical cloth is more energy-saving and environment-friendly;

3. the pile barrel is mainly applied to soft foundation, has four mechanisms of compaction, consolidation, drainage and pile foundation bearing force, can reduce carbon emission and does not damage the circulation of an underground water system, belongs to an environment-friendly pile body, and is suitable for popularization and application;

4. the invention can effectively drain the road surface water into the pile cylinder and the soil mass around the pile cylinder, thus reducing the traditional road surface structure road arch transverse slope by about 1 percent and improving the driving comfort.

5. The method is applied to urban construction, is not only suitable for foundation treatment of various soil qualities, meets the requirements of bearing capacity, deformation and stability of the foundation, but also can permeate rainwater into soil bodies around the pile barrel and an underground water system through the pile body, can basically intercept all rainwater in general rainy seasons, has extremely obvious interception effect when meeting rain and flood disasters, and can greatly reduce the pressure of municipal drainage pipe networks.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:

fig. 1 is a schematic view of a longitudinal sectional partial structure of a roadbed in an embodiment of the invention, wherein arrows indicate water flow directions;

fig. 2 is a schematic view of a longitudinal sectional partial structure of a roadbed according to the second embodiment of the invention, wherein arrows indicate the water flow direction;

fig. 3 is a schematic view of a longitudinal section of a roadbed in the third embodiment of the invention, wherein arrows indicate the water flow direction;

fig. 4 is a schematic top view of the pile casing;

wherein:

the waterproof structure comprises a gravel cushion layer 1, a permeable geotextile 11, a dense base layer 2, a waterproof seal layer 3, a permeable base layer 4, an asphalt permeable layer 5, a pile tube 6, a geotextile 61, a bulk material 62, a water collecting chamber 7, a water drainage hole 71 and a structure 8.

Detailed Description

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.

Example one

The mode of the 'W' type drainage mode (as shown in figures 1 and 4) suitable for the highway pavement comprises the following specific steps:

s1, road surface layer processing: the part above the top surface of the foundation is sequentially provided with a gravel cushion layer 1, a compact base layer 2, a waterproof seal layer 3, a permeable base layer 4 and an asphalt permeable layer 5 from bottom to top to form a pavement structure, each layer is filled and compacted in a layered manner, and cross slopes for guiding rainwater seepage of the pavement are arranged on the permeable base layer 4 and the asphalt permeable layer 5; the thickness of the broken stone cushion layer 1 can be selected within the range of 30-50cm, the gradient of a cross slope is 0.5% -2%, the selection is determined according to actual conditions, the low point of the cross slope is located at the edge of a traffic lane, the cross slope is symmetrically arranged on two sides of a road and used for conducting drainage operation after water flow is converged to the cross slope;

in the step, the thickness of the asphalt permeable layer 5 is 6-12cm, and the specific surface layer thickness is determined by calculation according to the accumulated traffic volume; the thickness of the permeable base layer 4 is 30-60cm, the material of the permeable base layer 4 is graded broken stone, gravel and the like, and the permeable base layer 4 is paved in two or three layers according to the conditions of a compacting machine, traffic load and the like, so that the testing and accepting deflection meeting the design requirement is ensured;

s2, pile construction: the pile tube 6 is made of geotextile materials; constructing a pile foundation on the edge of the cross slope, driving the prepared pile cylinders 6 into the pile foundation, wherein the number of the pile cylinders 6 driven into the foundation is variable, and the pile cylinders are preferably arranged at equal intervals; the clear distance of one side, close to the driving road surface, of the driven pile cylinder 6 is not more than 50cm (the specific distance is selected according to actual conditions), because a ditch is excavated or reserved on the surface layer of the distance section, sand and stone permeable materials are filled after the construction of the pile cylinder 6 is completed, rainwater on the road surface is filtered through the sand and stone material of the section and reaches the pile cylinder 6 after penetrating, and the geotextile on the outer side of the pile cylinder 6 can play a role in isolating fine-grained soil wrapped with water flow;

in the step, pile cylinders 6 are arranged on both sides of the road, and a non-motor vehicle lane, a sidewalk, a roadside flower bed and the like can be arranged above the pile cylinders; the pile tube 6 is composed of a geotextile 61 with a closed bottom and an open top as an outer layer and a granular material 62 coated in the geotextile 61. The geotextile 61 is geotextile 61 such as geogrid, geotextile and the like, and the filling discrete material 62 is one or a mixture of more of gravel, steel slag or slag.

S3, the water collection chamber 7 is provided with: a water collecting chamber 7 is arranged on one side, away from the cross slope, of the externally-coated geotextile granular material pile, the water collecting chamber 7 is arranged at 1/4-1/3 positions above the externally-coated geotextile granular material pile and is connected with the externally-coated geotextile granular material pile, a water drainage hole 71 is formed in the water collecting chamber 7 and used for collecting water in the pile tube 6 to the water collecting chamber 7 and then discharging the water to a municipal pipe network through the water drainage hole 71;

s4, paving 5-10cm sand-stone cushion layers above the pile tube, the roadbed and the water collecting chamber 7, and leveling by plastering cement mortar to form a W-shaped drainage mode of a pavement, piles on two sides and the drainage hole 71.

In the embodiment, the bearing capacity of the traditional gravel pile foundation is improved due to the circumferential constraint of the geotextile; when the soft foundation is treated, because water exists below the soft foundation, sand or silt is easily wrapped and carried in the water lifting process to block a water seepage channel, and therefore the problem is solved ingeniously through the structural design of the pile cylinder 6.

In general rainfall seasons, rainwater permeates into pile cylinders 6 at two sides and soil bodies and underground water systems around the pile cylinders 6 through the OGFC asphalt permeable layer 5 and the permeable base layer 4 to form two water storage and water retaining bands, so that the effects of supplying water for greening, reducing the pressure of a drainage pipe network, saving water resources, adjusting urban climate and the like are achieved; present urban road surface forms waterproof plate body gradually because of load effect such as vehicle pedestrian down, only rely on current municipal drainage pipe network to get rid of rain sewage when meeting rain flood, the drainage form is single and easily receive the limitation, can not effectively get rid of great runoff, highway road surface W type drainage pattern is when meeting rain flood, regional interior water flow is great, when the water yield that infiltrates into a section of thick bamboo 6 in the unit interval is less than the water yield of infiltration, the water overflows into a section of thick bamboo 6 upper end, can connect municipal drainage pipe network by the outlet 71 of stake side water-collecting chamber 7, alleviate the disaster of urban flood disaster even stop greatly.

Example two

The mode of the 'V' -shaped drainage mode (as shown in figures 2 and 4) suitable for general buildings comprises the following specific steps:

s1, pile construction: constructing a pile foundation at a roadbed with a structure 8, and driving a pile barrel 6 into the pile foundation; the pile tube 6 in this step has the same structure as that in the first embodiment, and is not described herein;

s2, road surface layer treatment: the part above the top surface of the pile cylinder 6 is provided with a gravel cushion layer 1, a permeable geotextile 11, a permeable base layer 4 and a bituminous permeable layer 5 from bottom to top in sequence to form a pavement structure, the middle of the pavement is a structure 8, and waterproof sealing layers 3 are arranged around the structure 8 to prevent the inner bottom layer of the structure from getting damp; the water flow sequentially passes through the asphalt permeable layer 5, the permeable base layer 4, the permeable geotextile 11 and the broken stone cushion layer 1 on the outer side of the structure 8, then enters the pile cylinder 6, and is used for forming a V-shaped water seepage channel from top to bottom and then is discharged to a municipal pipe network;

in the step, the thickness of the gravel cushion layer 1 is 30-50cm, and the specific thickness selection value is determined according to the actual situation.

In this embodiment, the rainwater passes through the downward infiltration of pitch permeable bed 5 outside the building, sets up pile section of thick bamboo 6 in permeable base layer 4 below, for preventing the phenomenon of getting damp, sets up stagnant water sealing 3 in the terrace below of structure 8 and around it.

EXAMPLE III

The fully permeable drainage patterns (as shown in fig. 3 and 4) of sidewalks, squares, shafts and the like comprise the following specific steps:

s1, pile construction: constructing a pile foundation at the roadbed, and driving a pile barrel 6 into the pile foundation; the pile tube 6 in this step has the same structure as that in the first embodiment, and is not described herein;

s2, road surface layer treatment: the part above the top surface of the pile cylinder (6) is sequentially provided with a gravel cushion layer (1), a permeable geotextile (11), a permeable base layer (4) and an asphalt permeable layer (5) from bottom to top to form a pavement structure; the water flow direction of the road surface forms a full-penetration drainage mode for sidewalks, squares, channels and the like from top to bottom and is discharged to a municipal pipe network.

In the embodiment, the road surface is not provided with a cross slope, so that rainwater can sequentially seep downwards from top to bottom, and the road is suitable for road subgrades with small water quantity or for second-grade and below-second-grade roads.

The invention has the beneficial effects that:

the pile cylinder has the main characteristics of multiple functions of partial soft soil replacement, compaction and reinforcement of loose foundations, drainage consolidation and pile foundation bearing force transmission, low carbon emission in the construction process, no damage to underground water systems, and belongs to an environment-friendly pile body. The geotextile (namely the outer layer structure of the pile tube in the invention) is acid and alkali resistant and corrosion resistant, and the granular pile is broken stone, slag or steel slag.

The steps, principles and the like which are not explicitly described in the present invention are all available to those skilled in the art according to conventional technical means, and therefore, are not described in detail.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. An environment-friendly roadbed processing method based on a sponge city is characterized in that: presetting a pile foundation on a pretreated foundation, and then driving a pile barrel (6) into the pile foundation, so that water flow is drained into a municipal pipe network after permeating into the pile barrel (6);

the pile barrel (6) is composed of a geotextile (61) with a closed bottom and an open top as an outer layer and a discrete material (62) coated in the geotextile (61).

2. The environment-friendly roadbed processing method based on the sponge city as claimed in claim 1, wherein the method comprises the following steps: the discrete material (62) is one or a mixture of a plurality of crushed stone, steel slag or slag.

3. The environment-friendly roadbed processing method based on the sponge city as claimed in claim 2, characterized in that: the method comprises the following specific steps:

s1, road surface layer processing: the part above the top surface of the roadbed is sequentially provided with a gravel cushion layer (1), a compact base layer (2), a waterproof seal layer (3), a permeable base layer (4) and an asphalt permeable layer (5) from bottom to top to form a pavement structure, and transverse slopes for guiding rainwater seepage of the pavement are arranged on the permeable base layer (4) and the asphalt permeable layer (5);

s2, pile construction: constructing a pile foundation on the edge of the cross slope, and driving a pile barrel (6) into the pile foundation to ensure that water in the cross slope is gathered and then permeates into the outer geotextile granular-body pile;

s3, the water collection chamber (7) is provided with: a water collecting chamber (7) is arranged on one side, away from the cross slope, of the pile tube (6), the water collecting chamber (7) is arranged at 1/4-1/3 positions of the upper portion of the pile tube (6) and is connected with the pile tube, a water drainage hole (71) is formed in the water collecting chamber (7) and used for collecting water in the pile tube (6) to the water collecting chamber (7) and then discharging the water to a municipal pipe network through the water drainage hole (71);

s4, paving sand and stone cushions above the pile tube (6) and above the roadbed and the water collecting chamber (7) and leveling to form a W-shaped drainage mode.

4. The environment-friendly roadbed processing method based on the sponge city as recited in claim 3, characterized in that: in step S1, the gradient of the cross slope is 0.5% to 2%.

5. The environment-friendly roadbed processing method based on the sponge city as recited in claim 3, characterized in that: in the step S2, the clear distance between the pile tube (6) and the side close to the driving road surface is less than or equal to 50 cm.

6. The environment-friendly roadbed processing method based on the sponge city as claimed in claim 2, characterized in that: the method comprises the following specific steps:

s1, pile construction: constructing a pile foundation at a roadbed with a structure (8), and driving a pile barrel (6) into the pile foundation;

s2, road surface layer processing: the part above the top surface of the pile cylinder (6) is sequentially provided with a gravel cushion layer (1), a permeable geotextile (11), a permeable base layer (4) and an asphalt permeable layer (5) from bottom to top to form a pavement structure, the middle of the pavement is provided with a structure (8), and waterproof sealing layers (3) are arranged around the structure (8); water flows on two sides of the structure (8) sequentially pass through the asphalt permeable layer (5), the permeable base layer (4), the permeable geotextile (11) and the gravel cushion layer (1) on the outer side of the structure and then enter the pile cylinder (6), and then are discharged to a municipal pipe network after forming a V-shaped water seepage channel from top to bottom.

7. The environment-friendly roadbed processing method based on the sponge city as recited in claim 2, characterized in that: the method comprises the following specific steps:

s1, pile construction: constructing a pile foundation at the roadbed, and driving a pile barrel (6) into the pile foundation;

s2, road surface layer processing: the part above the top surface of the pile cylinder (6) is sequentially provided with a gravel cushion layer (1), a permeable geotextile (11), a permeable base layer (4) and an asphalt permeable layer (5) from bottom to top to form a pavement structure, and the water flow direction of the pavement forms a fully-permeable drainage mode from top to bottom and is discharged to a municipal pipe network.