Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a granite residual soil roadbed structure and a construction method thereof.
The utility model provides a granite residual soil roadbed structure, including the bottom isolation layer, granite residual soil filling area, geotechnological check room zone of protection, five parts on intensity compensation layer and road surface structure layer, granite residual soil filling area's bottom is the bottom isolation layer, granite residual soil filling area's both sides are geotechnological check room zone of protection respectively, geotechnological check room zone of protection includes left geotechnological check room bank protection and right geotechnological check room bank protection, granite residual soil filling area's top is intensity compensation layer and road surface structure layer, road surface structure layer's underlayment and basic unit are cement stabilization gravel layer, underlayment and basic unit are whole full-spread structure.
The top of the bottom isolation layer is filled with residual granite soil, and the loose paving thickness of each layer of the residual granite soil is less than 30 cm.
Left geotechnological check room bank protection and right geotechnological check room bank protection comprise the geotechnological check room respectively, and geogrid is by the HDPE of high strength or PP copolymerization material broadband, and the netted check room structure that forms through powerful welding or riveting punches on the copolymerization material broadband, and geotechnological check room stretch-draw is opened and is formed the inner chamber space, and the all edge walls of geotechnological check room adopt the U shaped nail to fix in the earth's surface.
The subbase layer and the basic unit of the pavement structure layer are cement stabilized gravel layers, the subbase layer and the basic unit are of a whole full-width paving type structure, and a closed central separation belt is arranged on the pavement structure layer.
A construction method of a granite residual soil roadbed structure comprises the following steps:
before the granite residual soil subgrade is filled, the distribution and the quantity of the granite residual soil subgrade are checked, and a reasonable subgrade soil-stone blending scheme is determined.
Secondly, selecting typical granite residual soil to perform geotechnical tests such as water content, compaction, liquid-plastic limit, screening and CBR, determining the natural water content, the optimal water content, the maximum dry density, the liquid-plastic limit, the particle grading and the CBR of the granite residual soil, drawing a relation curve of the CBR and the water content, and respectively determining the rolling water content range of the granite residual soil of each part according to the control standard of the CBR of the granite residual soil filling part.
Selecting a typical filling subgrade construction point to pave a granite residual soil subgrade test road section, determining the airing mode and the airing speed of the granite residual soil, and summarizing the mechanical combination, compaction mechanical specification, loose paving thickness, rolling times, rolling speed and compaction quality control standard construction process parameters of the granite residual soil subgrade.
Paving strength compensation layers with different thicknesses at a test section of the granite residual soil roadbed, and controllably determining the thickness of the strength compensation layer based on the deflection value of the top surface of the strength compensation layer; before large-area construction of granite residual soil, construction measurement and lofting are carried out, and surface cleaning and compaction are carried out on the ground surface according to design requirements.
Also comprises the following steps:
filling a layer of material with high porosity and good water stability, such as gravel soil, gravel soil and mountain digging stone slag with the thickness of not less than 50cm, on the ground surface after surface cleaning and compaction, feeding a first layer of granite residual soil, controlling the loose paving thickness of the granite residual soil by adopting a method of drawing gray grids and hanging lines, roughly leveling by adopting a bulldozer after feeding, finely leveling by adopting a grader, rolling and detecting according to the construction process and the compaction standard determined by the test road section, and feeding, paving, leveling, rolling and detecting a second layer of granite residual soil roadbed after meeting the compaction standard.
And then sequentially carrying out feeding, paving, leveling, rolling and detection on granite residual soil at the third, fourth and Nth positions.
And shaping the slope surface of the slope when the granite residual soil is filled for 2m, and paving the geocell protection in time until the granite residual soil is filled to the design elevation of the bottom surface of the strength compensation layer.
Feeding, paving, leveling and rolling the first layer of strength compensation layer above the granite residual soil filling area; and rolling layer by layer to the top surface elevation of the strength compensation layer according to the relevant standard requirements, and carrying out roadbed acceptance.
And finally paving a pavement structure layer, wherein before the pavement structure layer is paved, the granite residual soil roadbed is subjected to at least one complete rainy season or a natural settling stabilization period of 6 months.
The invention has the advantages that the roadbed structure can utilize the granite residual soil to the maximum extent to fill the roadbed, and can avoid the erosion of the granite residual soil slope, the bottom isolation layer 2 of the granite residual soil roadbed structure can avoid the migration of water caused by water level rise or capillary action to the granite residual soil filling area 3, and can improve the roadbed stability. The geocell protection area can prevent slope runoff from eroding the slope under rainfall conditions, and the stability of the embankment body of the granite residual soil slope is improved. The cast-in-place or precast concrete guardrail closed central division strip 7 can prevent water in the division strip from infiltrating into the roadbed, and prevent the granite residual soil roadbed from generating uneven settlement deformation and strength attenuation. The strength compensation layer can ensure that the roadbed has enough structural strength and provides a bearing foundation for the pavement structure layer.
The granite residual soil roadbed structure can effectively prevent rainfall runoff from eroding granite residual soil side slopes, prevent water from infiltrating into the granite residual soil roadbed, ensure the stable humidity of a granite residual soil filling area 3, ensure the stable long-term performance of the granite residual soil roadbed, be more convenient to construct and low in manufacturing cost, and can utilize the granite residual soil to the maximum extent.
Detailed Description
The invention is further illustrated with reference to the following figures and examples.
It will be apparent that those skilled in the art can make many modifications and variations based on the spirit of the present invention.
As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element or component is referred to as being "connected" to another element or component, it can be directly connected to the other element or component or intervening elements or components may also be present. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art.
The following examples are further illustrative in order to facilitate the understanding of the embodiments, and the present invention is not limited to the examples.
Example 1: as shown in fig. 1, the roadbed structure with granite residual soil comprises five parts, namely a bottom isolation layer 2, a granite residual soil filling area 3, a geocell protection area, a strength compensation layer 5 and a pavement structure layer 6.
The bottom of the granite residual soil filling area 3 is a bottom isolation layer 2, the original earth surface 1 is subjected to surface cleaning and compaction and then is filled with the bottom isolation layer 2, the granite residual soil starts to be filled at the top of the bottom isolation layer 2, and the loose thickness of each layer of the granite residual soil is not more than 30cm until the granite residual soil is filled to the designed elevation of the bottom surface of the strength compensation layer 5; granite residual soil filling area 3 fills intensity compensation layer 5 in the top, lays the asphalt concrete pavement in intensity compensation layer 5's top at last, granite residual soil filling area 3's both sides are geotechnological check room zone of protection respectively, and geotechnological check room zone of protection includes left geotechnological check room bank protection 4 and right geotechnological check room bank protection 8, has closed central division strip 7 on the road surface structural layer 6, and granite residual soil filling area 3's top is intensity compensation layer 5 and road surface structural layer 6.
Left geotechnological check room bank protection 4 and right geotechnological check room bank protection 8 comprise the geotechnological check room respectively, and the porose range of the all peripheral walls of geotechnological check room, all peripheral wall interconnect between the geotechnological check room, and geotechnological check room stretch-draw is opened and is formed the inner chamber space, and the all peripheral walls of geotechnological check room adopt the U type nail to fix in earth's surface 1.
Example 2: as shown in fig. 1 and 2, a granite residual soil roadbed structure and a construction method thereof aim to solve the problem of reasonable utilization of granite residual soil as roadbed filler, and provide a road granite residual soil roadbed structure type which is more scientific, more convenient and faster in construction, higher in utilization rate, capable of avoiding side slope erosion and ensuring roadbed performance to be stable for a long time by comprehensively considering rainfall, roadbed pavement drainage, pavement structure form and side slope protection measures.
The invention provides a granite residual soil roadbed structure, which is shown in figure 1 and embodiment 1.
The granite residual soil filling part in the granite residual soil roadbed structure is an area between the bottom isolation layer 2 and the strength compensation layer 5, the filling height is not more than 15m, and the slope rate is 1: 1.5-1: 1.75.
The filler of the strength compensation layer 5 can adopt cement, lime and the like to improve granite residual soil, and can also adopt gravel soil, gravelly soil, mountain-opening stone slag and other coarse-grained soil with good water stability. The thickness of the strength compensation layer 5 is not less than 50cm, and may be determined by a test section according to a design deflection representative value, a filler of the strength compensation layer 5, and the like.
The central division strip on the pavement structure layer 6 of the asphalt concrete pavement is a closed central division strip 7 of a cast-in-place or precast concrete guardrail.
The subbase layer and the base layer of the pavement structure layer are cement stabilized gravel layers and are of a whole full-width full-paved structure.
The bottom isolation layer 2 is a gravel soil, gravel soil or mountain-opening stone slag filling layer with the filling thickness not less than (more than) 50 cm. The gravels in the gravels soil, the mountain digging stone slag and the like are hard stones and medium-hard stones with good water stability.
The geocell protection area is a granite residual soil subgrade slope surface full-paved geocell, and is anchored by hook-shaped riveting piles or U-shaped steel bars at a fixed interval of about 1 m; the grid space is filled with planting soil.
The geocell protection area and the granite residual soil roadbed are constructed synchronously, so that the protection is carried out along with filling, and the erosion and damage of granite residual soil side slopes are avoided.
Example 3: as shown in figure 2, the granite residual soil roadbed structure and the construction method comprise the following steps:
before the granite residual soil subgrade is filled, the distribution and the quantity of the granite residual soil subgrade are checked, and a reasonable subgrade soil-stone blending scheme is determined.
Secondly, selecting typical granite residual soil to perform geotechnical tests such as water content, compaction, liquid-plastic limit, screening and CBR (cubic boron reactor), determining the natural water content, the optimal water content, the maximum dry density, the liquid-plastic limit, the particle gradation and the CBR of the granite residual soil, drawing a relation curve of the CBR and the water content, and respectively determining the rolling water content range of the granite residual soil of each part according to the control standard of the CBR of the granite residual soil filling part; selecting a typical filling roadbed construction point to pave a granite residual soil roadbed test section, determining the airing mode and the airing speed of the granite residual soil, and summarizing the construction process parameters of the mechanical combination, the compaction mechanical specification, the loose paving thickness, the rolling pass, the rolling speed, the compaction quality control standard and the like of the granite residual soil roadbed.
Paving strength compensation layers 5 with different thicknesses at a test section of the granite residual soil roadbed, and controllably determining the thickness of the strength compensation layers 5 based on the deflection value of the top surfaces of the strength compensation layers 5; before large-area construction of granite residual soil, construction measurement and lofting are carried out, and surface cleaning and compaction are carried out on the ground surface according to design requirements.
The method comprises the steps of filling a layer of materials with large porosity and good water stability, such as gravel soil, mountain digging stone slag and the like with the thickness not less than 50cm on the surface of the ground after surface cleaning and compaction, feeding a first layer of granite residual soil on the materials, controlling the loose thickness of the granite residual soil by adopting a manner of drawing gray grids and hanging lines, roughly leveling by adopting a bulldozer after feeding, finely leveling by adopting a grader, rolling and detecting according to a construction process and a compaction standard determined in a test road section, and feeding, paving, leveling, rolling and detecting a second layer of granite residual soil roadbed after meeting the compaction standard.
And then sequentially carrying out feeding, paving, leveling, rolling and detecting on granite residual soil at the third, fourth, …, Nth and other positions.
And shaping the slope surface of the slope when the granite residual soil is filled for 2m, and paving the geocell protection in time until the granite residual soil is filled to the design elevation of the bottom surface of the strength compensation layer 5.
The first layer of the strength compensation layer 5 is fed, paved, leveled and rolled and formed above the granite residual soil filling area 3; and (5) rolling layer by layer to the top surface elevation of the strength compensation layer 5 according to the relevant standard requirements, and carrying out roadbed acceptance check.
And finally paving a pavement structure layer 6, wherein before the pavement structure layer 6 is paved, the granite residual soil roadbed is subjected to at least one complete rainy season or a natural settlement stabilization period of 6 months.
As described above, although the embodiments of the present invention have been described in detail, it will be apparent to those skilled in the art that many modifications are possible without substantially departing from the spirit and scope of the present invention. Therefore, such modifications are also all included in the scope of protection of the present invention.