How to deal with road collapse? How to fix it?

The only way to collapse a pavement is to dig it up first, find out the cause of the problem, and then replace it, or take the method of drilling and grouting.

1. Uniform subsidence: It is caused by the subgrade and pavement to achieve further compacting and stability under the action of natural factors and driving, and generally does not cause pavement damage.

2. Uneven subsidence: due to the undense roadbed and pavement, uneven rolling, and deformation caused by driving under water erosion.

3. Local subsidence: due to the partial filling of the roadbed is not dense or the roadbed has tombs, dry wells, tree pits, trenches, etc., when it is eroded by water and sinks.

Hello dear, it is a pleasure to serve you! For you to find out the causes of pavement collapse, through a comprehensive analysis of the distribution location and scale range of the collapse area, starting from the safety, economy, construction difficulty, in line with the concept of "thorough management, file knowledge of safety and stability for comprehensive management", to ensure the safety and smoothness of the road. The collapse mainly exists on the non-motorized lanes and sidewalks, and at present, part of the collapsed road surface has been excavated for detailed investigation and analysis, and the hole in the Ant Xiang has been found and continued to excavate downward and around, and no funnel-shaped cavity has been found.

Thus the possibility of forming a cavity in the water return to the soil body in the underground pipeline is ruled out. In view of the shallow location of the roadbed cavity, the main measures are to repair after excavation, and at the same time strengthen water control measures to channel and improve the drainage system. 1. Local collapse pavement treatment method 1) remove the pavement and base layer of the collapsed area, dig down 80cm from the top of the original road bed, stop digging if the soil is hard, if the soil is still wet and soft, continue to excavate downward to a solid soil layer, and notify the technical personnel at the same time.

2) When encountering inspection wells, within 1m around the inspection well, dig to the top of the roadbed below the meter. 3) Before backfilling, the technical and quality inspection personnel must be notified to the site to check and agree to the backfill, and then the backfill can be carried out. 4) The backfill is made of 28 ash soil for backfilling, and the thickness of each layer of virtual filling is not more than 25cm.

After tamping to the top elevation of the design ash soil, the degree of compaction is tested until it meets the design requirements. 5) The hydraulically stabilized base layer in the original design is replaced by C25 concrete. 6) After the concrete is cured, restore the asphalt concrete surface layer.

Legal analysis: The technical measures to prevent and control ground subsidence include water control measures and engineering measures. Water control measures include:

In groundwater exploitation areas, groundwater levels should be reasonably controlled; In the mine dredging and drainage, local grouting treatment is adopted for the sections that may have ground subsidence; When draining the loose soil layer, it is necessary to control the pumping volume of the well, and not a large amount of water can be pumped, so as not to form a cavity and cause collapse; Groundwater extraction in karst cannot reduce the water level below the top layer of karst bodies or caves. Engineering measures include: backfilling, i.e. using clay or slag to fill the pit and compact; Blocking, for the collapse caused by dredging and drainage, the groundwater flow can be blocked by curtain grouting or water interception wall, and the collapse caused by the surface water flow can be isolated by building embankments and cofferdams The collapse caused by the karst cave can be plugged with a concrete plug; Reinforcement, when the foundation of the building collapses, it can be reinforced by methods such as pile support and foundation reinforcement.

Legal basis: Construction Law of the People's Republic of China

Article 36 Safety production management of construction projects must adhere to safety first.

First, the principle of putting prevention first, establish and improve the responsibility system for safe production and the system of mass prevention and treatment.

Article 37 The design of construction projects shall conform to the construction safety regulations and technical specifications formulated in accordance with the provisions of the State to ensure the safety performance of the project.

Article 38 When preparing the construction organization design, the construction enterprise shall formulate corresponding safety technical measures according to the characteristics of the construction project; For highly specialized engineering projects, special safety construction organization designs shall be prepared and safety technical measures shall be taken.

Hello, 1Pavement collapse is mainly caused by the lack of strict control of subgrade filler, and the highway subgrade construction code stipulates that under normal circumstances, materials that cannot be compacted to the specified density and cannot form a stable fill cannot be used for subgrade filling.

2. Groundwater overexploitationThe land subsidence caused by groundwater overexploitation is a slow and regional process, which is usually due to excessive pumping of groundwater, destroying the original structure of the stratum, causing soil instability, burying hidden dangers, and causing sudden collapse of the road surface when encountering underground construction or long-term soaking of rainwater.

3. Soil loss is mainly due to the frequent occurrence of rainfall in summer, which aggravates the erosion of the subgrade soil, deforms the ground rainwater nullah, and the underground pipeline ruptures, and the infiltration water dilutes the surrounding soil, resulting in the loss of the surrounding soil and the sudden collapse of the road surface. Thank you.

The causes of road collapse are uneven settlement of subgrade, uneven settlement of base structure, pavement load and construction disturbance.

1. Uneven settlement of roadbed.

1) The subgrade filler control is not strict, and the highway subgrade construction specification stipulates that under normal circumstances, the materials that cannot be compacted to the specified density and cannot form a stable fill cannot be used for subgrade filling.

2) Improper treatment of wet and soft foundation, before filling the subgrade in the soft soil section, the bearing capacity of the foundation should be first investigated, and then a reasonable soft foundation treatment scheme and construction technology should be adopted.

3) subgrade earthwork filling is not real, the filler of each layer of subgrade filling is not leveled with grader or other leveling machinery or the leveling effect is not good, when the roadbed stone square or earth-rock mixture is filled, the stone block diameter is too large, so that the compactness of the stone-filling embankment or the earth-stone mixture embankment can not meet the requirements of the specification.

4) the compaction standard at the junction of filling and excavation is inconsistent, and some construction units fail to construct according to the requirements of the specification in the construction, and the subgrade compaction machine is insufficient, so that the compactness of the subgrade soil is low, and the permeability of the soil is enhanced, so that the subgrade soil is softened and produces uneven settlement.

5) The backfill compaction degree of the structure platform back is insufficient, and the most easily ignored thing in the backfill of the platform back is that although the middle part of the filling meets the requirements, the edge is impermeable filler, and it is not replaced, so the water accumulation infiltrated by the road surface exists in the platform back, and the stability of the roadbed is affected for a long time, and the platform back is subsided.

2. The base structure is unevenly settled.

The construction materials are unqualified, and the sand and gravel are mostly taken from the spot, and the stone grades are different. If the gradation of the materials used in the base construction is unreasonable, the quality of cement concrete is difficult to guarantee.

3. Pavement load.

In recent years, the number of large-tonnage vehicles has increased year by year, and the number of overloaded and overrun vehicles has increased the internal stress generated by the road surface to exceed the design load of concrete, and plastic deformation and cracks have appeared. Under the long-term, high-frequency, and overload heavy collision of the pavement, the cracks will continue to expand, increase, thicken, and lengthen, and finally lead to the subsidence and damage of the pavement.

4. Construction disturbance.

After the construction of the underground pipeline, the backfill is not real, the soil is loose, and under the influence of various factors such as groundwater and vehicle vibration, it is easy to cause quicksand erosion, forming a roadbed cavity, and finally causing the road surface to collapse. For example, the construction of subway tunnels is easy to cause stratum disturbance, and a large amount of groundwater seeps out, so that a large amount of sediment in the upper or surrounding loose soil layer is carried away, and a cavity is gradually formed, resulting in the collapse of the road surface.

The foundation of the road surface is unstable, and the geological soil is loose; second, a pipeline and sewer were built underground, which was improperly constructed, resulting in ground collapse; Third, when the road is repaired, the quality of the foundation is not up to par, etc., and secondly, there is that the load of the passing vehicle exceeds the load-bearing weight of the road. All of these causes can cause the road surface to collapse.

(1) According to the main causes of collapse, it can be divided into two categories: natural collapse and man-made collapse. The former is caused by natural factors such as vibration, rainfall and rainwater infiltration into the ground, self-weight pressure, underground erosion and hollowing, etc.; The latter is the collapse of the ground due to human actions, such as water inrush in underground mining, tunnel drainage or construction, large extraction of groundwater, storage and diversion of water in reservoirs, etc. In these two categories, it can be further divided into many types according to the specific inducing factors that cause subsidence, such as ** collapse, mine goaf collapse, rainfall seepage collapse, drainage collapse, pumping collapse, water storage collapse, ground load overload collapse, blasting and other vibration collapse.

2) According to whether there is karst phenomenon in the subsidence area, it is divided into karst ground collapse and non-karst ground collapse. Karst ground subsidence mainly occurs in areas where underground karst (i.e., hidden karst) exists, and its distribution is wide, the number is large, the frequency is high, the inducing factors are many, and it has strong concealment and suddenness characteristics. According to the nature of the rock and soil in the subsidence area, non-karst ground collapse can be further divided into various types such as loess collapse in the Loess Plateau area, lava collapse in the volcanic lava distribution area and freeze-thaw collapse in the permafrost area, among which the loess collapse is mainly distributed in the Northwest Loess Plateau area, and the distribution and damage range of the latter types of collapse are relatively small.

3) Underground mining of mines: underground mining activities cause a certain range of goafs, so that the upper rocks and soil lose support, resulting in ground collapse.

4) Drainage and water inrush (mud inrush) in underground engineering: mines, tunnels, civil air defense projects and other underground projects, due to the drainage and dredging of groundwater or water inrush (mud inrush), the groundwater level is rapidly reduced, and the original stress balance state of surface rock and soil above it is unbalanced, and it collapses when there is an underground cavity. The resulting karst ground collapse is the largest in scale and intensity, and the most harmful.

1: Because of subgrade settlement. We have a large area of water that has sunk due to the loss of groundwater due to quarrying, and the road is just accidentally damaged.

2: Because of the erosion of the roadbed. The construction of culvert drainage pipes and urban sewage pipes is not standardized, or because the waterproof layer of the asphalt pavement is not done well, etc., so that the roadbed soil is washed away and a cavity is formed.

3: There is a karst cave under the roadbed. It might happen, I guess.

Pavement collapse is a common technical problem in modern highway construction. To solve these problems, the most critical is foundation construction, followed by pavement construction, the construction unit should be designed in accordance with the requirements, and the technical specifications are strictly required.

In addition, overloading and overloading of vehicles is also an important cause of road collapse. Management and maintenance, in addition to daily maintenance, should also be scientifically managed, road transport strict requirements not overloaded, not overrun, how to avoid and deal with road collapse accidents.

1. Causes of road collapse.

1. Uneven settlement of roadbed.

1) The control of subgrade filler is not strict.

The highway subgrade construction code stipulates that, under normal circumstances, materials that cannot be compacted to the specified density and cannot form a stable fill cannot be used for subgrade filling.

2) Improper disposal of wet and soft foundations.

Before filling the subgrade in the soft soil section, the bearing capacity of the foundation should be explored first, and then a reasonable soft foundation treatment plan and construction technology should be adopted. The filler of each layer of subgrade filling is not leveled with grader or other leveling machinery or the leveling effect is not good, and when the subgrade stone square or earth-stone mixture is filled, the stone block diameter is too large, so that the compactness of the stone-filled embankment or the earth-stone mixture embankment can not meet the requirements of the specification.

4) The compaction standards at the fill-and-dig junction are inconsistent.

Some construction units fail to construct according to the requirements of the specification in the construction, and the subgrade compaction machine is insufficient, so that the compactness of the subgrade soil is low, and the permeability of the soil is enhanced, so that the subgrade soil is softened and uneven settlement is produced.

5) The backfill compaction of the back of the structure is insufficient.

The most easily ignored thing in the backfill of the platform back is that although the middle part of the filling meets the requirements, the impermeable filler at the edge is not replaced, so the water accumulation infiltrated by the road surface exists in the back of the platform, and the stability of the roadbed is affected for a long time, causing the back of the platform to subside.

2. Uneven settlement of grassroots institutions.

1) The construction materials are unqualified, and the sand and gravel are mostly taken locally, and the stone grades are different. Other materials vary from one construction unit to another, and some of them have quality problems.

2) If the grading of the materials used in the base construction is unreasonable, the quality of cement concrete is difficult to guarantee.

3. Pavement load.

In recent years, the rapid development of cargo transportation, the increase of large-tonnage vehicles year by year, the increase of overloaded and overrun vehicles makes the internal stress generated by the road surface bear the car load to exceed the design load of concrete, the concrete produces plastic deformation, and cracks appear. Under the long-term and overloaded heavy impact, the cracks that appeared before continued to expand, increased, thickened, and lengthened, and finally caused the pavement to subside and collapse.

4. Construction disturbance.

1) The construction of subway tunnels, including shield method, shallow buried and underground excavation method, is easy to cause stratum disturbance, a large amount of underground seepage, so that a large amount of sediment in the upper or surrounding loose soil layer is taken away, and a cavity is gradually formed, resulting in the collapse of the road surface.

2) Due to the design and construction problems of the construction dewatering well, the fine particles in the formation are taken away in the long-term pumping process, breaking the original soil balance, and gradually forming a cavity, and when the supporting force of the upper soil layer is insufficient, the road surface collapses.