Method for forming interface between bridge roadway and embankment
FIELD: building, particularly bridge building.
SUBSTANCE: method involves compacting ground of embankment body and cones; forming drainage layers and water-draining chutes on coating; creating pad with variable rigidity decreasing in direction from bridge along embankment for length equal to approach slab length; arranging approach slab having upward gradient in bridge direction. Pad of embankment body is formed by creating cast-in-place piles along with surface compaction of upper cast-in-place pile parts and upper embankment layer, wherein transversal cast-in-place piles form strips having medium rigidity jointly with ground forming embankments. The medium rigidity is reduced from maximal value at bridge pier to minimal one at approach slab end opposite to bridge pier.
EFFECT: reduced embankment subsidence under approach slab due to decreased pad and draining material displacement in horizontal direction.
8 cl, 6 dwg
The present invention is intended for device pairing roadway of the bridge embankment mainly roads and can be used in bridge engineering.
During the construction of bridges on the roads below category III pair of bridge embankment is not arranged as pedestrian bridges). Over time, in place of the pair is formed drawdown of the mound, which affects the entry and exit of the bridge. The device would eliminate this disadvantage, however, is associated with relatively high costs when using existing manufacturing techniques mates roadway of the bridge embankment.
On the roads of I-III categories to ensure a smooth transition from elastic deformations of the embankment to a more rigid deformations of the superstructure as according to their size and speed leaks in places mates bridge embankment create a special transitional areas in the form of adapter plates, blind areas and pillows from crushed stone and sand and gravel materials that you want the layers to be sealed, (Bridges and structures on the roads. Edited Pamalakaya. M, Transport, 1991, V.1, str). Adapter plates one end rest on the ledge of the Cabinet wall and the other on concrete Lejeune. Boards are placed on the bed of drainage material with a slope of 1:10 in the direction of the embankment and fix with pins./p>
Operations that characterize the above-described method of manufacturing a pair of the roadway of the bridge embankment, are as follows: perform soil dumping in the body of the mound and its cones with layer-by-layer seal, drainage layer and drainage trays on the floor, creating a cushion in the body of the mound along the length equal to the length of the transition plate with variable stiffness, decreasing from the bridge along the embankment.
The disadvantages of this method pair of bridge embankment are:
a) the possibility of shear pillows and drainage material in the horizontal direction that ultimately leads to the settlement of the transition plate;
b) the complexity of the design pair that is associated with the need to use concrete Lejeune, bag of crushed stone and sand and gravel materials that you want the layers to be sealed. This leads to relatively rapid subsidence of the embankment under Lejeune. In addition, greatly complicated and same increase production work on the device interface bridge embankment.
There is a method of pairing the bridge embankment on the roads (see, for example: Bigscreen. Pair of bridge embankment on the roads. M., publishing house of Mahr, 1939, p.16-17), which consists in installing a wooden shield with a slope of 4° in the side of the bridge, which is at the top covered with sand with the mos device is new. The disadvantage of this method is small, the durability associated with wooden shield, which under the action of load, deformation, and under the influence of moisture rot. In addition, sediment occurs not only under the action of vertical forces arising from the impact of transport, it is necessary or entering the bridge, but also from the horizontal movement of soil embankments. Moving from vertical forces accumulate, forming a permanent deformation. The accumulation of such deformations will be the more intense, the greater the difference in the stiffness of the drive on the floor and the bridge. A role in the formation of deformations of the embankment near the bridge play the cones of the subgrade. The stability of the cone depends on the soil properties used in its place (draining ability, the volume of freezing), and angle of pledging that is not provided in a known manner mates bridge embankment.
There is a method of pairing the bridge embankment (see, for example: MRI. A pair of bridge embankment. Road, No. 11, 1968, p.16-17), implying the device backfill soil in the cross between the support and the body of the mound, his seal, implementation draining backfill and tape drainage. The zone of active deformation of the embankment block special transition plates of sufficient length. the La asphalt concrete pavement are buried adapter plates, for cement concrete surface slabs.
The disadvantage of this method is the necessity of arranging high permeability. Furthermore, this method of pairing does not provide variable stiffness mates from the embankment to the bridge. Should the abutment to choose this type, so that the water from the soil subgrade could be diverted into the side holes of the bridge, so there are restrictions in relation to the choice of the coast supports. The main disadvantage of this method is precipitation under the action of vertical forces due to the horizontal displacement of the cushion and drainage material.
The closest analogue to the technical essence and the achieved result is a method of manufacturing a pair carriageway highway bridges with embankment (MRL. The pairing of the carriageway highway bridges with bulk. M, Transport, 1976, p.49-50), which consists in dumping gravel and crushed stone cushion, the thickness of which is determined by calculation, the drainage layer and drainage trays on the floor, laying on gravel-gravel pad of Lejeune to support one end of the transition plate, layered soil compaction in the body of the mound and its cones, device, gravel and crushed stone pillows with variable stiffness, decreasing from the bridge along the embankment in length, equally is th length of the transition plate, laying transition plate with the elevation angle of the side of the bridge. The other end of the transition plate is based on a surge of inner wall (draft Soundobject) or top (draft Giproavtotrans). The last solution is less effective because of the small rotation of the transition plate in the vertical plane is the disorder of an expansion joint. The hinged rotation of the plates is provided on a support pin connection.
The disadvantages of the known method of manufacturing a pair of the roadway of the bridge embankment are:
a) the possibility of shear pillows and drainage material in the horizontal direction, which leads to the settlement of the transition plate;
b) the complexity of the design pair that is associated with the need to use concrete Lejeune, pillows of stone and draining material that you want the layers to be sealed;
C) when the horizontal displacement of the abutment model mate completely useless, as the adapter plates are shifted from the Cabinet wall.
The technical problem solved by the invention is to reduce precipitation of the embankment under the transition plate, the lower horizontal displacement pillows and draining material, simplifying the design of the coupling and its manufacturing technology.
This is due to the fact that the method is of izgotovlenie mates carriageway road bridge from embankment including soil compaction in the body of the mound and its cones, a drainage layer and drainage trays on the floor, creating a cushion with variable stiffness, decreasing from the bridge along the embankment length equal to the length of the transition plate, the device transition plate with the elevation angle of the side of the bridge, a pillow in the body of the mound is performed by forming rows of piles placed along and across the embankment surface seal top of piles and the upper layer of the embankment, cross ramming piles to form, together with the ground, stacked in piles, bands with medium hardness, the average stiffness is reduced from the maximum size of abutment of the bridge to a minimum at the opposite abutment of the bridge region of the transition plate. Under the average stiffness of the embankment is understood weighted average stiffness, defined as the ratio of the stiffness of emolument and the surrounding soil per unit volume of the embankment. This set of operations allows the use of ramming piles instead of laying transition plate (assuming directly on the piles can be laid road surface), or create a variable stiffness of the embankment under the transition plate, ensuring the stiffness of the soil in the embankment in the vertical direction due to the bearing capacity ramming piles and in the horizontal direction due to ill the bones of the body of the pile. In addition, the stiffness of the soil in the body of the mound is enhanced by deep compaction occurring during the molding ramming piles. Surface compaction of the top layer of the embankment and of piles creates a uniform density of top of piles and the surrounding soil, which, ultimately, increases the reliability of the design of the pair of bridge embankment.
The average stiffness of the embankment performed by reducing the number of piles placed in parallel rows, as the distance from the abutment of the bridge. This operation allows you to withstand the average stiffness of the embankment, without resorting to layered dumping gravel and crushed stone layers and their layer-by-layer seal.
Ramming piles perform with variable carrying capacity by changing their lengths and/or diameters in each subsequent row of abutment of the bridge. The changing lengths of piles in each subsequent row of abutment of the bridge provides a variable stiffness of the embankment from the support of the bridge to the edge of the transition plate and at the same time this operation is effective in terms of technology, as it allows to use the same means of mechanization, for example, punch, punch, to achieve the required rigidity regardless of the location of the piles relative to the supports of a bridge.
The variable reaches the bearing capacity of piles for the odd simultaneous changes in their lengths and diameters in each subsequent row from the foundations of the bridge allows you to optimize the parameters of the piles at minimum manufacturing cost and to provide a variable stiffness of the soil in the embankment under the transition plate.
In addition, adjacent piles in each row of the mound perform different diameter and length. This set of operations allows to optimise the production process, i.e. in the presence of punches of different diameters can be molded piles of different diameter, reaching the necessary rigidity in the corresponding band of the mound.
Also ramming piles perform the contour of the embankment, across the incline of the abutment of the bridge, and at some distance from him. This surgery considerably increases the stiffness of the embankment in the horizontal direction, eliminates the need for devices Lejeune and increases the resistance of the cone and slopes.
Also, each subsequent row of piles positioned coaxially with the preceding row or staggered. Placing each of a number of piles coaxially previous series allows you to achieve maximum strength of the embankment in place leaning on her transition plates, and their placement in a checkerboard pattern allows to optimize the strength of the embankment and drainage ability.
In addition, the adapter plate is mounted in the upper part of piles and make it removable. This design interfacing transmission of the forces from sliding down or entering the bridge transport directly on the pile, which increases the reliability involves what I carriageway road and bridge providing lower horizontal displacement pillows and draining material and significantly reducing the cost of subsequent repairs.
Also the adapter plate perform in one piece with printed piles. This operation will significantly increase the strength of the pairing of the roadway embankment with a bridge, which is especially important for bridges of I-III categories with heavy traffic.
The essence of the proposed technical solution is illustrated by the example of a specific implementation and the accompanying drawings. Figure 1 shows the scheme of the proposed method of coupling the bridge embankment in longitudinal section; figure 2 is a top view (transition plate removed) single-row placement of piles; 3 - double-row placement of piles when ramming piles are arranged coaxially in series (top view with removed transition plate); 4 - double-row placement of piles when ramming piles are arranged in a checkerboard pattern (top view with removed transition plate); figure 5 - placement of piles throughout the area occupied by the transition plate (top view with removed transition plate); 6 - the process formation of piles by pneumotropica.
The essence of the proposed method of manufacturing a pair carriageway road bridges with embankment is as follows.
In mound 1 is formed into ramming piles 2 (1)Their lie along the slope of the mound 1 and across it (figure 2-5) with surface seal top of piles and the upper layer of the embankment. Cross ramming piles form (together with the soil, laid in mound 1) bands with medium stiffness, determined by the stiffness of the soil and of piles. Transverse rows have at abutment 3 bridge 4 and at the end of the transition plate 5, and the average stiffness of the strip embankment 1, located directly on the abutment 3 bridge 4, more than the average stiffness of the strip at the opposite abutment of the bridge region of the transition plate 5. When performing a transition plate 5 she removable front end fit on a burst of an inner wall or abutment 3 axle 4, as in figure 1, and the rear end on a transverse row of piles 2 serving as Lejeune to hold transition plate 5. The front row of piles 2 serves to enhance the stability of the cone 6 of the mound 1, and hence the stability of the embankment 1. Ramming piles 2 can be produced with variable carrying capacity, and maximum load capacity of a number of piles 2, which are placed in abutment 3 bridge 4, and gradually their load-carrying capacity decreases with distance from the abutment 3 bridge 4. Change the bearing capacity of piles 2 can be achieved in three ways. The first way is with the same diameter ramming piles 2 to make them different depths. As is known, the bearing capacity ramming piles 2 depends on the area of the lateral surface, so ramming piles 2 are the same diameter the tra, but different lengths will have different loading capacity. The second way is the manufacture of piles 2 are of identical length but different diameter. The result is the same. It is possible to use the combined method, i.e. manufacturing printed 2 piles of different diameters and different lengths, and this can be done in different rows, when in the same row bearing capacity ramming piles varies due to its length, in another series - through diameter, or in each row. In the latter case, ramming piles 2 are interleaved, that is, one pile is formed long, but small diameter, the other is short but large diameter, the Main thing is that the average stiffness of the strip embankment 1 would be consistent with the settlement. The optimal solution depends on the production conditions (the required average density of the embankment, physico-mechanical properties of filled in mound 1 soil drainage properties, availability of equipment, allowing to produce ramming piles required length and diameter) and minimise human and financial costs. Ramming piles 2 can be arranged in one row along the contour (figure 2) or in several rows, arranged coaxially relative to each other in the horizontal plane (figure 3), or in a checkerboard pattern (figure 4). Possible layout of piles 2 across the horizontal surface of the coupling, as shown in figure 5. This case of alsoobe is but to use in the construction of bridges, traffic intensity which is low. You can do without the use of adapter plates. Directly on the top of piles placed pavement. In this case, yourself ramming piles function of the transition plate. If the bridge higher categories with heavy traffic, it is possible to fill the concrete top of piles with subsequent concreting of the transition plate. In the end, the transition plate is made with printed piles as a whole. You can execute a removable transition plate, which falls freely on the ends of piles (these operations are described above). The choice of the method of manufacturing a mate (in the form of paving on the field of piles, combining concrete slab with a pile heads, removable device transition plate) depends on the category of the road and bridge, operating conditions, production conditions.
In the formation of piles the upper part becomes rasuplotnenie. Properties of soil around the piles also change due to a possible recovery of the surface of the mound in the formation of piles. Therefore, it is advisable to spend a surface seal for the alignment properties of the soil adjacent to the surface and top of piles, before laying transition plate
The optimal location of piles 2 depends on the production conditions, the selected diameter of piles 2, square pair of axle 4 with bulk 1, which is the length of the transition plate. The important point is the ability to remove water, which is formed as a result of rainfall or snow melt, through the gaps between adjacent printed piles 2, which is achieved by choosing the distance between them.
Method of manufacture of piles 2 can be any. The most appropriate use for this purpose air puncher - self-propelled percussion device for forming holes in compacted soil. Figure 6 shows the technology of stage molding process ramming piles 2. Figure 6 a shows the operation on the introduction of the punch 7 in mound 1. After passing through the bore 8 of the required length air puncher extracted from it by reversing its course. Educated well 8 (figb) has a solid wall due to the radial shift of the soil and seal the latter. As a result, the radial compression of the soil volume occupied by the well volume 8. The next step is filling the hole 8 inert material 9, which may be sand, gravel, etc. In principle, this can be limited, as printed pile 2 it is formed. However, if it is necessary to form a hole, and hence the printed pile of larger diameter when using the punch 7 of the same diameter (the same power), the molding process ramming piles 2 should continue. On filled with inert material 9 hole 8 are repeated sinking (high), forming a bore 8 of the same diameter as the diameter of the punch 7. The walls of the well 8 more compacted than the surrounding soil 1, that is formed as a circular layer with a more compacted soil. Then the cavity of the hole 8 is filled with an inert material (fige), resulting in a printed pile 2 of larger diameter, and therefore with greater load carrying capacity. It is possible to perform the driving of pneumotropica 7 filled borehole (figs) and then the process can be repeated, starting from the operation shown in Figg the result is printed pile 2 is still larger diameter. Almost was obtained printed pile 2 500 mm in diameter with five-sinking pneumotropica IP diameter 130 mm Hole with a larger diameter can also be formed using an extender with a more powerful pneumotropica. Here the availability of more powerful punches and minimize labor and capital expenditures.
After forming the grid of piles 2 the alignment properties of the upper part and the surrounding soil at the ends of piles laid transition plate 5, which further relies on them.
Round pile has the same stiffness in all directions, so it provides the same resistance at loads in any direction. This property provides both the stability of slopes and cones, and the stiffness of the embankment 1 under transition plate 5, which increases the durability of the pair of axle 4 with embankment 1. The distance between adjacent printed pile 2 is selected so as to ensure drainage of water accumulated in the body of the mound 1. Reducing the stiffness of the transverse strips of the mound 1 can be achieved by reducing the bearing capacity of piles 2 from bridge 4 to the side of the mound 1, therefore, provides a smooth transition of deformation both in the size and speed of their course.
1. A method of manufacturing a pair of the roadway of the bridge embankment, including soil compaction in the body of the mound and its cones, a drainage layer and drainage trays on the floor, creating a cushion with variable stiffness, decreasing from the bridge along the embankment length equal to the length of the transition plate, the device transition plate with the elevation angle of the side of the bridge, characterized in that the cushion in the body of the mound is performed by forming rows of piles placed along and across the embankment surface seal top of nabuna the pile and the top layer of the mound, cross ramming piles to form, together with the ground, stacked in piles, bands with medium hardness, the average stiffness is reduced from a maximum at the abutment of the bridge to a minimum at the opposite abutment of the bridge region of the transition plate.
2. The method according to claim 1, characterized in that the average stiffness of the embankment performed by reducing the number of piles in parallel rows as the distance from the abutment of the bridge.
3. The method according to any one of claims 1 and 2, characterized in that ramming piles perform with variable carrying capacity by changing their lengths and/or diameters in each subsequent row of abutment of the bridge.
4. The method according to any one of claims 1 to 3, characterized in that adjacent piles in each row of the mound perform different diameter and length.
5. The method according to claim 1, characterized in that ramming piles perform the contour of the mound - across the incline of the abutment of the bridge, and at some distance from him.
6. The method according to any one of claims 1 to 4, characterized in that each subsequent row of piles positioned coaxially with the preceding row or staggered.
7. The method according to any one of claims 1 to 6, characterized in that the adapter plate is mounted in the upper part of piles and make it removable.
8. The method according to any one of claims 1 to 6, characterized in that the adapter plate perform in one piece with printed piles.
FIELD: building, particularly for erecting foundations for industrial and civil building, for constructing piles in seasonally freezing ground.
SUBSTANCE: pile comprises upper part made of reinforced concrete, lower part made of ground and reinforced with time-hardening mortar injected in it. Pile has at least one inner injection channel. Upper end of upper pile part comprises means, particularly reinforcement extensions, to connect thereof to structure supported by pile. Lower end of upper part rests upon lower pile part. Each injection channel extends along the full pile length. Upper pile part is made as truncated cone with greater base facing down. Cone has hu height, bo and bu widths of upper and lower bases correspondingly. bo and bu are selected from the following: bu ≤ bo + 2hu. Lower pile end is made as convex widening with minimal transversal direction of not less than bu. Height hl of lower pile part is determined from a given relation.
EFFECT: increased bearing capacity, provision of lower pile part strength alternating along pile height along with decreased labor inputs and production cost.
3 cl, 5 dwg
FIELD: building, particularly for slope consolidation and for stabilizing deep front landslide areas.
SUBSTANCE: structure includes foundation mat and piles formed in wells grouped in rows. Upper pile parts are embedded in foundation mat, lower one is restrained by not-sliding ground layers. Piles are composite along their lengths. Central pile parts are not filled with concrete. Heights of upper and lower pile parts decrease towards landslide head. Structure to prevent deep front land-slides comprises separate local pile groups connected by foundation mats and located within landslide body boundaries. Each foundation mat has tension bars anchored in stable slope layers and arranged under and above foundation mat along slope to retain thereof against displacement and rotation.
EFFECT: improved slope stability, increased operational reliability of structure built on wide landslides, reduced building time and material consumption.
FIELD: building, particularly hydraulic structure reinforcement.
SUBSTANCE: method is performed in two-stages. The first stage involves forming vertical elongated flat ground massifs secured by hardening material. Massifs are created in crest embankment area and in upper area of embankment slope so that massifs are spaced minimal available distance from crest and pass through embankment body, including land-sliding upper embankment slope area. Massifs are anchored in mineral bottom by lower edges thereof and are arranged at least in three rows and there are at least three massifs in each row. Method for massifs forming involves driving double-slotted injectors directly in embankment ground or in wells formed in embankment and having plugged wellhead; orienting injector slots perpendicular to hydraulic pressure head vector direction in embankment area to be reinforced; injecting hardening material under increased pressure across horizons from top to bottom or in reverse direction, wherein injection is initially performed under 5-15 atm pressure and at minimal rate in each second injector of one outermost row beginning from extreme ones; feeding hardening material in previously missed injectors in this row; supplying injectors of another extreme row with hardening material in the same way; feeding hardening material to ejectors of medium rows under 10-20 atm pressure; performing the second reinforcement stage as material hardens to obtain 70% strength. The second reinforcement stage involves forming vertical elongated flat massifs of secured ground anchored in mineral bottom by lower edges thereof and arranged at least in three rows, wherein each one includes at least three massifs. Massifs extend at the angle exceeding embankment slope angle to horizontal line. Massifs are formed with the use of double-slotted injectors in remainder embankment area. Injector slots are directed perpendicular to hydraulic pressure head vector direction in embankment area to be reinforced. Hardening material is ejected in above succession, wherein hardening material pressure is equal to design process pressure enough for direction of feeding hardening material through injector slots and lesser than hardening material injection pressure of the first reinforcement stage.
EFFECT: increased reliability of structure reinforcement; prevention of land-slide on structure slopes.
3 cl, 3 dwg
FIELD: bridge building, particularly bridge pier protection against ice load applied thereto.
SUBSTANCE: bridge pier includes foundation piling composed of panel to connect pile row and ice-protection enclosure attached to piles in ice formation area. Ice-protection enclosure is made as hollow metal box connected to lower panel part and/or to pile bodies through tie rods and having vertical cylindrical members surrounding the piles and spaced apart from the piles. Gaps between cylindrical member walls and piles are filled with binding material. Box interior has longitudinal-transverse stiffening ribs and consists of several sections.
EFFECT: reduced metal consumption for enclosure building, increased strength of foundation piling and increased rate of mounting thereof.
2 cl, 3 dwg