Settlement observation method for junction of new and old roads

Abstract

The application discloses a settlement observation method for the joint of new and old roads, which comprises the following steps: embedding multiple vertical grouting pipes equidistantly along the direction of the road line, opening grouting holes on the grouting pipes for grouting, embedding the top of the grouting pipes into the road surface layer, embedding the bottom of the grouting pipes into the joint of the new and old roadbeds, inserting a vertical reinforcing bar into each embedded grouting pipe, making the lower end of the reinforcing bar extend into the old roadbed and the upper end of the reinforcing bar extend out of the road surface, marking a scale line parallel to the road surface at the upper end of the vertical reinforcing bar by using paint, measuring the vertical distance between the top of each grouting pipe and the scale line marked on the reinforcing bar in the grouting pipe after a period of time, and judging that the new roadbed at the position has settlement if the measured distance changes greatly compared with the initial state, so that the grouting pipe can be filled with concrete for hardening treatment without damaging the road surface after the settlement observation is normal, and the method is suitable for various new and old joint roads and has wide applicability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of road construction, and particularly relates to a settlement observation method for the junction of new and old roads. BACKGROUND

[0002] With the continuous development of social economy and the continuous construction of modern cities, rural highways gradually begin to be reformed, and most road construction needs to re-pave new roadbeds on the original roadbeds to carry out road construction. During the junction of new and old roadbeds, the old roadbeds have been in operation for many years and are subjected to the long-term action of load, and the settlement tends to be stable. However, after the construction of new roadbeds, a large amount of settlement will occur. If no consideration and treatment are given to this aspect, the settlement will easily lead to the cracking and depression of the road surface, thereby causing damage to the highway. Settlement observation is to observe the settlement degree of the observation point set according to the building and the fixed (permanent) measuring point, express the settlement degree with data, and confirm whether the roadbed has a large-scale settlement through the data. When the settlement occurs, the settlement position is treated in time to prevent the road surface from being damaged due to the settlement of the roadbed.

[0003] The prior art provides some road settlement observation methods, which can solve the problems of damaged road settlement observation points and unknown settlement depth. However, these technologies also have some deficiencies, such as complicated installation process, high cost, easily damaged components, need to damage the road surface, affect vehicle traffic, and need to improve the monitoring accuracy and data reliability. SUMMARY

[0004] The present application aims to solve the problems of the prior art, such as complicated installation process, high cost, easily damaged components, need to damage the road surface, affect vehicle traffic, and need to improve the monitoring accuracy and data reliability.

[0005] The present application adopts the following scheme: a settlement observation method for the junction of new and old roads, comprising the following steps:

[0006] (1) During the construction of the roadbed, a plurality of vertical grouting pipes are pre-buried along the road line direction at equal intervals, the grouting pipe is provided with a grouting hole for grouting, the top of the grouting pipe is buried into the road surface layer, and the bottom of the grouting pipe is buried above the junction of the new and old roadbeds;

[0007] (2) A vertical reinforcing bar is inserted into each pre-buried grouting pipe, so that the lower end of the reinforcing bar extends into the old roadbed and the upper end of the reinforcing bar extends out of the road surface;

[0008] (3) A scale line parallel to the road surface is marked on the upper end of the vertical reinforcing bar using paint or the like;

[0009] (4) After a predetermined time, the vertical distance d between the top of each grouting pipe and the scale line marked on the reinforcing bar inside the grouting pipe is measured;

[0010] (5) If the measured distance d changes greatly from the initial state, it is determined that the newly built roadbed at the location has settled, the steel reinforcement in the grouting pipe is extracted, and the grouting pipe is used to grout and reinforce the settled roadbed;

[0011] (6) If the measured distance d does not change significantly, it is determined that the newly built roadbed at the location has not settled, the steel reinforcement (1) in the grouting pipe is extracted, and concrete of the same grade as the road surface is poured at the grouting pipe embedding position for reinforcement treatment.

[0012] Further, the vertical reinforcement is a steel reinforcement.

[0013] Further, before step (2), the following step is further included: a plurality of control points A of known elevations are arranged near the grouting pipe to determine the elevation Hb of the top of each grouting pipe.

[0014] Further, the method for determining the elevation Hb of the top of each grouting pipe is: a control point A of known elevation H is arranged near the grouting pipe, the elevation Ha of the A point is confirmed through drawings during the arrangement of the control point, and the elevation Hb of the top of the settlement observation pipe is measured and calculated.

[0015] A steel reinforcement 1 is inserted into the embedded grouting pipe until the old roadbed. Due to the long-term effect of load on the old roadbed after years of operation, the settlement tends to be stable, and the steel reinforcement will not settle. Therefore, a scale line is marked on the steel reinforcement at the corresponding position of the road elevation B with red paint. Finally, the elevation of the grouting pipe setting position is Hb = Ha + a - b.

[0016] a and b respectively represent the readings of the leveling rod when placed at points A and B, and in the case of monitoring the value of Hc, the marked position of the grouting pipe 2 top and the steel reinforcement 1 confirmation can also be used to determine whether the roadbed has settled.

[0017] Further, in step (3), the scale line marked on the steel reinforcement uses paint with good weather resistance or a welded metal marker.

[0018] Further, in step (4), the method for measuring the vertical distance d between the top of the grouting pipe and the scale line on the steel reinforcement is: two target papers or reflectors are installed at the top of the grouting pipe and the scale line respectively, and a range finder or a total station is used to accurately measure the distance between the two target points.

[0019] Further, in step (5), when the settled roadbed is grouted and reinforced, cement-based grouting material or water glass-based grouting material is injected through the grouting pipe.

[0020] Further, the grouting pipe has a hollow structure, and a flange is arranged on the outer surface of the pipe body to increase the friction with the roadbed.

[0021] Further, the pipe body of the grouting pipe is made of reinforced concrete or plastic to improve the strength and corrosion resistance of the pipe body, and a detachable sealing cover is arranged at the pipe top end of the grouting pipe to facilitate the insertion and removal of the steel bars during construction.

[0022] Further, in step (1), a plurality of grouting pipes are embedded along the road line direction at equal intervals, and the embedding interval of the grouting pipes is determined according to the roadbed soil condition and the road grade, and the interval ranges from 5 meters to 30 meters; for the road section with better roadbed soil and higher compaction degree, the embedding interval of the grouting pipes can be appropriately increased; for the road section with poor roadbed soil and lower compaction degree, the embedding interval of the grouting pipes can be appropriately reduced; in step (1), the pipe bottom embedding depth of each grouting pipe is controlled within the range of 30-100 centimeters above the junction of the new and old roadbeds.

[0023] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0024] (1) The settlement observation method for the junction of the new and old roads of the present application solves the problem of large-area destruction of the road surface required by the settlement observation device by inserting the steel bars into the old roadbed and the road surface and monitoring the roadbed settlement through the position of the grouting pipe top and the corresponding scale line, and achieves the purpose of not damaging the road surface and hardening the grouting pipe filled with concrete after the settlement observation is not a problem.

[0025] (2) The settlement observation method for the junction of the new and old roads of the present application solves the problem that the settlement observation device cannot be processed in time after observation by the method of inserting the grouting pipe into the roadbed, and achieves the purpose of directly grouting the abnormal place.

[0026] (3) The settlement observation method for the junction of the new and old roads of the present application solves the problem that the new roadbed is more likely to sink and is not easy to observe in the new and old roadbeds by using the grouting pipe for monitoring and repairing, and achieves the purpose of timely observation and processing of the settlement place, and the method is cheap in cost and suitable for various new and old junction roads, and has wide applicability. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a road profile schematic diagram of the preferred embodiment of the present application;

[0028] Figure 2 It is a road plan view of the preferred embodiment of the present application;

[0029] Figure 3 It is a road elevation measurement diagram of the preferred embodiment of the present application;

[0030] The reference signs in the drawing respectively represent: 1-steel bar, 2-grouting pipe; DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0032] The present application is further described below in combination with the drawings:

[0033] As a slow deformation geological disaster, land subsidence has a great adverse effect on water conservancy projects, industrial and agricultural production, transportation, urban construction, ecological environment, etc. The development of land subsidence monitoring means is extremely important. Based on the existing technology, the main means for monitoring land subsidence in China are: leveling method, trigonometric leveling method, GPS technology, digital photogrammetry method, InSAR method, optical fiber monitoring technology, etc. In view of the existing subsidence observation technology, the purpose of the present application is to provide a method which can measure the approximate position of the subsidence of the road subgrade and timely treat the subsidence position in the process of just occurring subsidence, so as to achieve the effect of protecting the road surface. Specifically, the method comprises the following steps:

[0034] Step one: a plurality of grouting pipes 2 are pre-buried along the line in the road during road construction, the top of the pipe is buried into the road surface layer, and the bottom of the pipe is buried into the upper part of the junction of the new and old road subgrade. After the burial is completed, a control point A with a known elevation H is set near the grouting pipe, and in the process of setting the control point, the elevation Ha of point A is confirmed through the drawing, so as to facilitate the measurement and calculation of the elevation Hb of the top of the subsidence observation pipe B.

[0035] Step two: a steel bar 1 is inserted into the buried grouting pipe until the old road subgrade. Due to the long-term effect of load on the old road subgrade after years of operation, the subsidence tends to be stable, and the steel bar will not subsidence. Therefore, a scale line is marked on the corresponding position of the road elevation B with red paint. Finally, the elevation of the grouting pipe setting position is Hb=Ha+a-b.

[0036] a and b respectively represent the readings of the leveling rod when the leveling rod is placed to points A and B. In the case of monitoring the value of Hb, whether the road subgrade subsidence occurs can also be judged by observing the marked position of the grouting pipe 2 top and the steel bar 1 confirmation position.

[0037] Step three: after a period of time, the difference between the top of the subsidence pipe and the scale line marked on the steel bar 1 is measured to measure the difference between the elevation of the newly built road and the original design elevation, and the value is used to confirm whether the newly built road has subsidence. If subsidence occurs, step four is used; if no subsidence occurs, step five is used.

[0038] Step four: through the analysis result of step three, if the value is too large, it can be confirmed that the new foundation has settlement, through the grouting pipe 2 of the steel bar 1 in the settlement occurs after the extraction, through the grouting pipe 2 to the settlement occurs in the part of grouting, to achieve the purpose of protecting the pavement.

[0039] Step five: through the analysis result of step three, if the value has no obvious change, it can be confirmed that the new foundation has not occurred settlement, then the steel bar 1 in the grouting pipe 2 is extracted and the concrete with the same mark as the road is poured at the buried grouting pipe to reinforce the place.

[0040] Those skilled in the art readily understand that the above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A settlement observation method for a new-old road junction, characterized by, It comprises the following steps: Step 1: During the construction of the road subgrade, a plurality of vertical grouting pipes (2) are embedded equidistantly along the road direction, the grouting pipes (2) are provided with grouting holes for grouting, the top of the grouting pipe (2) is embedded into the pavement surface layer, and the bottom is embedded to above the junction of the new and old subgrade; Step 2: A steel bar (1) is inserted into each embedded grouting pipe (2), so that the lower end of the steel bar (1) extends into the old subgrade, and the upper end extends out of the pavement; Step 3: A scale line parallel to the pavement is marked on the upper end of the steel bar (1) using paint; Step 4: After a predetermined time, the vertical distance (d) between the top of each grouting pipe (2) and the scale line marked on the steel bar (1) inside is measured; Step 5: If the measured distance (d) changes greatly from the initial state, it is determined that the new subgrade at this position has settled, the steel bar (1) inside the grouting pipe (2) is extracted, and the grouting pipe (2) is used to grout and reinforce the settled subgrade part; Step 6: If the measured distance (d) does not change significantly, it is determined that the new subgrade at this position has not settled, the steel bar (1) inside the grouting pipe (2) is extracted, and the same grade concrete as the pavement is poured at the embedded position of the grouting pipe (2) for reinforcement treatment.

2. The method of settlement observation of new-old road interface according to claim 1, characterized in that: Before Step 2, the following steps are further included: a plurality of control points (A) with known elevations are arranged near the grouting pipe (2), and the elevation (Hb) of the top of each grouting pipe (2) is determined.

3. The method of settlement observation of new-old road interface according to claim 2, characterized in that: The method for determining the elevation (Hb) of the top of each grouting pipe (2) is: a control point A with a known elevation H is arranged near the grouting pipe, the elevation Ha of point A is confirmed through drawings during the arrangement of the control point, and the elevation Hb of the top of the settlement observation pipe is measured and calculated; A steel bar (1) is inserted into the embedded grouting pipe until the old subgrade; due to the long-term effect of load on the old subgrade after years of operation, the settlement tends to be stable, and the steel bar will not settle, so a scale line is marked on the steel bar at the corresponding position of the road elevation B using red paint; finally, the elevation of the grouting pipe setting position is Hb=Ha+a-b; a and b respectively represent the readings of the leveling rod when the leveling rod is placed at points A and B, and in the case of monitoring the value of Hb, whether the subgrade settlement occurs is determined by observing the marked position of the grouting pipe (2) and the steel bar (1) at the confirmation position.

4. The method of settlement observation of new-old road interface according to claim 1, characterized in that: In Step 3, the scale line marked on the steel bar (1) uses paint with good weather resistance or a welded metal marker.

5. The method of settlement observation of new-old road interface according to claim 1, characterized in that: In Step 4, the method for measuring the vertical distance (d) between the top of the grouting pipe (2) and the scale line on the steel bar (1) is: two target papers or reflective sheets are installed at the top of the grouting pipe (2) and the scale line respectively, and a range finder or a total station is used to accurately measure the distance between the two target points.

6. The method for observing settlement of new-old road interface according to claim 1, wherein: In Step 5, when grouting and reinforcing the settled subgrade part, cement-based grouting material or sodium silicate-based grouting material is injected through the grouting pipe (2).

7. The method for observing settlement of new-old road interface according to claim 1, wherein: The grouting pipe (2) has a hollow structure, and a flange is provided on the outer surface of the pipe body to increase the friction with the subgrade.

8. The method for observing settlement of new-old road interface according to claim 1, wherein: The pipe body of the grouting pipe (2) is made of reinforced concrete or plastic to improve the strength and corrosion resistance of the pipe body, and the top end of the grouting pipe (2) is provided with a detachable sealing cover to facilitate the insertion and removal of the reinforcing steel bars (1) during construction.

9. The method according to any one of claims 1-8, characterized in that: In step one, a plurality of grouting pipes (2) are embedded at equal intervals along the direction of the road route, and the embedded interval of the grouting pipes (2) is determined according to the soil quality of the roadbed and the road grade, and the interval ranges from 5 meters to 30 meters; for road sections with better roadbed soil quality and higher compaction degree, the embedded interval of the grouting pipes (2) is increased; for road sections with poorer roadbed soil quality and lower compaction degree, the embedded interval of the grouting pipes (2) is decreased; in step one, the pipe bottom of each grouting pipe (2) is embedded to a depth of 30-100 centimeters above the junction of the new and old roadbeds.

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