Construction process for subgrade and pavement of settlement section in municipal road engineering

Abstract

The invention relates to the technical field of road engineering, and discloses a settlement section roadbed and pavement construction process in municipal road engineering, which comprises the following steps: S1, preparing construction materials; s2, performing pavement layer construction; s3, stone layer construction is conducted; and S4, foundation treatment is conducted. According to the settlement section roadbed and pavement construction process in the municipal road engineering, through structure optimization, loess collapsibility and foundation deformation are effectively reduced, through improvement of foundation materials, original loess collapsibility and non-deformability of the original loess collapsibility are further improved, a wireless communication technology Lora is used, and the settlement section roadbed and pavement construction process has the advantages that the settlement section roadbed and pavement construction process is simple, convenient and practical. A plurality of sensors are connected into a network by using a spread spectrum technology in which communication at different transmission rates does not interfere with each other, real-time acquisition and transmission of data are realized, and the data are transmitted to a data center or a cloud platform, so that constructors can find and solve problems in time through the data, and the construction efficiency is improved. Errors caused by lack of real-time monitoring in the actual working process are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of road engineering, and in particular to a construction process for a roadbed and pavement in a settlement section of a municipal road engineering project. Background Art

[0002] Road engineering is a comprehensive system engineering project with roads as the object, which has obvious technical, economic and management characteristics. It covers many aspects, including roadbed engineering, pavement engineering, bridge engineering, tunnel engineering, drainage engineering, etc. Each part cooperates with each other to form a complete road system.

[0003] Application publication number CN109112918A discloses an anti-settlement roadbed and its construction method. This anti-settlement roadbed is composed of a pavement layer, a gravel layer, a lime-soil improved loess layer, a filler layer, a compensation layer, a reinforced concrete layer and a compacted loess layer from top to bottom; the pavement layer is an asphalt concrete pavement, and a water collecting pipe and a drainage pipe are arranged in the gravel layer, and the water collecting pipe is connected to the outside through the drainage pipe; the lime-soil improved loess layer is formed by lime-soil improved loess; the filler layer is a foundation formed by loess, lime and glass fiber in a mass ratio of 100:6 to 10:0.5 to 1.2; the compensation layer includes three rammed earth layers and two crushed stone layers, and a crushed stone layer is arranged between every two rammed earth layers. This application reduces the settlement of the roadbed from the aspects of avoiding the collapsibility of loess and enhancing the anti-deformation ability of loess.

[0004] However, the above method has some defects when used. On the one hand, there is still room for further improvement in the original loess collapsibility and its anti-deformation ability. On the other hand, in the actual paving process, there is a lack of real-time monitoring of the settlement and deformation of the roadbed. Summary of the invention

[0005] The purpose of the present invention is to provide a construction process for the subsidence section of a municipal road project, so as to solve the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: A construction process for subgrade and pavement of a settlement section in a municipal road project, comprising the following steps: S1: Prepare construction materials. According to the design requirements, prepare high modulus asphalt concrete, microporous elastic asphalt layer materials, waterproof insulation materials, gravel, highly absorbent resin particles, nano-modified loess, and lightweight high-strength fillers; S2: Carry out the pavement layer construction, first lay the high modulus asphalt concrete upper layer, then lay the microporous elastic asphalt lower layer on it, and set a waterproof barrier between the two layers. During the construction process, ensure that each layer of material is laid evenly and tightly to avoid gaps and cracks; S3: Carry out gravel layer construction. On the basis of the traditional gravel layer, add a drainage network that is interwoven horizontally and vertically, and fill it with highly absorbent resin particles to ensure that the drainage network is unobstructed and the highly absorbent resin particles are evenly distributed; S4: Carry out foundation treatment, mix nano-modified loess and lightweight high-strength filler in a certain proportion, evenly lay them on the foundation, and use layered dynamic compaction technology for compaction to ensure the close combination of each layer of material and the density of the foundation.

[0007] Preferably, the thickness of the upper layer of high modulus asphalt concrete is 5-10 cm, and the thickness of the lower layer of microporous elastic asphalt layer is 3-8 cm.

[0008] Preferably, the waterproof barrier is made of polyethylene film or waterproof coating, and the drainage pipe network is made of polyethylene or polypropylene material, with a diameter of 1-3 cm and a spacing of 5-15 cm.

[0009] Preferably, the particle size of the highly water-absorbent resin particles is 0.5-2 mm, and the water absorption rate is 500-2000 g / g.

[0010] Preferably, the loess is modified by using nano-silicon dioxide and nano-alumina to improve the strength and water resistance of the loess and reduce its collapsibility. The contents of nano-silicon dioxide and nano-alumina in the nano-modified loess are 5-15% and 2-8%, respectively.

[0011] Preferably, polystyrene foam particles mixed with fly ash and slag powder are used as part of the lightweight and high-strength filler to reduce the deadweight of the foundation. The mass ratio of polystyrene foam particles, fly ash and slag powder is 1:1-3:0.5-2. The layered dynamic compaction technology uses a high-frequency vibratory roller for compaction, and its vibration frequency is 25-35Hz and the amplitude is 0.5-1.5mm.

[0012] Preferably, S4 comprises the following steps: S41: Mixing process, including pretreatment, mixing and secondary mixing, crushing and screening loess, removing impurities, ensuring the uniformity of loess particles, putting the pretreated loess, nano silicon dioxide and nano alumina into a mixer in a certain proportion, mixing them fully, mixing polystyrene foam particles, fly ash and slag powder in a certain proportion, crushing and screening, putting nano modified loess and light high strength filler into a mixer in a certain proportion, and performing secondary mixing; S42: Laying process, including base treatment, layered paving and watering for moisture retention. Before paving, clean and level the base of the foundation to ensure that there is no debris or water on the surface of the base. Lay the mixed foundation materials in layers according to the thickness required by the design. After each layer is laid, use a roller for preliminary compaction. During the paving process, water is sprinkled in time to keep moisture, and the watering should be even and appropriate to avoid too much or too little. Drainage facilities should be reserved during the paving process. S43: Compaction process, including initial compaction, recompacting and final compaction. Initial compaction is carried out immediately after paving is completed. During the initial compaction, the travel speed and vibration intensity of the roller are controlled. After the initial compaction is completed, recompacting is carried out, and the vibration intensity and travel times of the roller are appropriately increased. After the recompacting is completed, final compaction is carried out using static compaction.

[0013] Among them, in the mixing process of S41, the mixer is an existing technology. During the mixing process, the speed and time of the mixer are controlled to ensure that the nanomaterials can be evenly distributed on the surface of the loess particles. The secondary mixing can ensure that the two can be fully integrated to form a uniform foundation material.

[0014] During the laying process of S42, initial compaction is performed to ensure that the material can fit tightly on the base layer, and watering is used to keep it moist to avoid cracks in the material due to drying.

[0015] In the compaction process of S42, the initial compaction can make the foundation material initially stable, reduce the displacement and deformation of the material, and avoid excessive impact on the foundation material by controlling the driving speed and vibration intensity of the roller. The secondary compaction is used to further improve the density and strength of the foundation material. At this time, increasing the driving speed and vibration intensity can ensure that the foundation material reaches the density required by the design. Static pressure is used for final compaction. On the one hand, it can avoid causing excessive vibration to the foundation material, and on the other hand, it can eliminate wheel marks and cracks on the foundation surface, making the foundation surface flatter and smoother.

[0016] Preferably, the Internet of Things technology is introduced during the construction process of S2, S3, and S4 to carry out intelligent monitoring and feedback adjustment, monitor the settlement and deformation of the roadbed in real time, and dynamically adjust the construction parameters such as compaction degree and paving thickness according to the monitoring data to ensure that the roadbed quality is controllable.

[0017] Preferably, the equipment used for intelligent monitoring and feedback adjustment includes a displacement sensor, an inclination sensor, a stress strain sensor, a level and an Internet of Things sensor network.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are: First, the present invention adopts high modulus asphalt concrete as the upper layer and a microporous elastic asphalt layer as the lower layer, and a waterproof barrier is arranged between the two layers, which enhances the bearing capacity of the road surface, improves the drainage efficiency, and reduces the settlement caused by water loss. By adding a transverse and longitudinal interlaced drainage network and the highly absorbent resin particles filled therein, the road surface seepage water is quickly collected and discharged, the humidity of the loess layer is further reduced, and the risk of collapse is reduced. Through structural optimization, the collapse of loess and foundation deformation are effectively reduced.

[0019] Second, the present invention utilizes nano-silicon dioxide and nano-alumina to modify loess, which has lower collapsibility and higher bearing capacity, can effectively reduce foundation deformation, and uses lightweight high-strength fillers to reduce the weight of the foundation itself, thereby improving the overall stability of the foundation. By improving the foundation material, the original loess collapsibility and its anti-deformation ability are further improved. The initial pressure can make the foundation material initially stable, reduce the displacement and deformation of the material, and avoid excessive impact on the foundation material by controlling the driving speed and vibration intensity of the roller. The re-pressing is used to further improve the density and strength of the foundation material. At this time, increasing the driving speed and vibration intensity can ensure that the foundation material reaches the density required by the design. Static pressure is used for final pressure. On the one hand, it can avoid excessive vibration of the foundation material, and on the other hand, it can eliminate wheel marks and cracks on the foundation surface, making the foundation surface flatter and smoother.

[0020] Third, in the present invention, the displacement sensor uses a laser displacement sensor to measure the displacement of the roadbed surface, which can detect potential settlement or deformation problems. The inclination sensor is used to monitor the change in the inclination angle of the roadbed and evaluate the overall stability and deformation trend of the roadbed. The stress and strain sensor uses a fiber grating sensor to measure the stress and strain state inside the roadbed, which helps to understand the stress condition and deformation degree of the roadbed material. The level is used to perform high-precision leveling and angle measurement to obtain the elevation change of the roadbed surface. The Internet of Things sensor network is composed of the above multiple sensors and uses the wireless communication technology Lora. It uses its long-distance, large-capacity, low-energy consumption, and its spread spectrum technology with different transmission rates that will not interfere with each other to connect multiple sensors into a network, realize real-time data collection and transmission, and transmit these data to the data center or cloud platform, so that construction personnel can use these data to timely discover and solve problems, avoiding errors caused by lack of real-time monitoring in the actual work process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the implementation process of the present invention; DETAILED DESCRIPTION The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Embodiment 1 See also Figure 1 The present invention provides a technical solution: a construction process for the subgrade and pavement of a settlement section in a municipal road project, comprising the following steps: S1: Prepare construction materials. According to the design requirements, prepare high modulus asphalt concrete, microporous elastic asphalt layer materials, waterproof insulation materials, gravel, highly absorbent resin particles, nano-modified loess, and lightweight high-strength fillers; S2: Carry out the pavement layer construction, first lay the high modulus asphalt concrete upper layer, then lay the microporous elastic asphalt lower layer on it, and set a waterproof barrier between the two layers. During the construction process, ensure that each layer of material is laid evenly and tightly to avoid gaps and cracks; S3: Carry out gravel layer construction. On the basis of the traditional gravel layer, add a drainage network that is interwoven horizontally and vertically, and fill it with highly absorbent resin particles to ensure that the drainage network is unobstructed and the highly absorbent resin particles are evenly distributed; S4: Carry out foundation treatment, mix nano-modified loess and lightweight high-strength filler in a certain proportion, evenly lay them on the foundation, and use layered dynamic compaction technology for compaction to ensure the close combination of each layer of material and the density of the foundation.

[0023] The thickness of the upper layer of high modulus asphalt concrete is 5-10 cm, and the thickness of the lower layer of microporous elastic asphalt layer is 3-8 cm.

[0024] The waterproof barrier is made of polyethylene film or waterproof coating, and the drainage pipe network is made of polyethylene or polypropylene material, with a diameter of 1-3cm and a spacing of 5-15cm.

[0025] The particle size of the super absorbent resin particles is 0.5-2 mm, and the water absorption rate is 500-2000 g / g.

[0026] Loess is modified with nano-silicon dioxide and nano-alumina to improve its strength and water resistance and reduce its collapsibility. The contents of nano-silicon dioxide and nano-alumina in nano-modified loess are 5-15% and 2-8% respectively.

[0027] Polystyrene foam particles mixed with fly ash and slag powder are used as part of the lightweight and high-strength filler to reduce the deadweight of the foundation. The mass ratio of polystyrene foam particles, fly ash and slag powder is 1:1-3:0.5-2. The layered dynamic compaction technology uses a high-frequency vibratory roller for compaction with a vibration frequency of 25-35Hz and an amplitude of 0.5-1.5mm.

[0028] S4 includes the following steps: S41: Mixing process, including pretreatment, mixing and secondary mixing, crushing and screening loess, removing impurities, ensuring the uniformity of loess particles, putting the pretreated loess, nano silicon dioxide and nano alumina into a mixer in a certain proportion, mixing them fully, mixing polystyrene foam particles, fly ash and slag powder in a certain proportion, crushing and screening, putting nano modified loess and light high strength filler into a mixer in a certain proportion, and performing secondary mixing; S42: Laying process, including base treatment, layered paving and watering for moisture retention. Before paving, clean and level the base of the foundation to ensure that there is no debris or water on the surface of the base. Lay the mixed foundation materials in layers according to the thickness required by the design. After each layer is laid, use a roller for preliminary compaction. During the paving process, water is sprinkled in time to keep moisture, and the watering should be even and appropriate to avoid too much or too little. Drainage facilities should be reserved during the paving process. S43: Compaction process, including initial compaction, recompacting and final compaction. Initial compaction is carried out immediately after paving is completed. During the initial compaction, the travel speed and vibration intensity of the roller are controlled. After the initial compaction is completed, recompacting is carried out, and the vibration intensity and travel times of the roller are appropriately increased. After the recompacting is completed, final compaction is carried out using static compaction.

[0029] Through the above technical scheme, high modulus asphalt concrete is used as the upper layer, and the lower layer is a microporous elastic asphalt layer. A waterproof barrier is arranged between the two layers, which enhances the bearing capacity of the road surface, improves drainage efficiency, and reduces settlement caused by water loss. The newly added transverse and longitudinal interlaced drainage pipe network and the highly absorbent resin particles filled therein can quickly collect and discharge road surface seepage water, further reduce the humidity of the loess layer, and reduce the risk of collapse. Through structural optimization, the collapse of loess and foundation deformation are effectively reduced. The loess is modified with nano-silicon dioxide and nano-alumina, which has lower collapse and higher bearing capacity, can effectively reduce foundation deformation, and use lightweight and high-strength fillers to reduce the ground The deadweight of the foundation body can improve the overall stability of the foundation. By improving the foundation materials, the original loess collapsibility and its anti-deformation ability are further improved. The initial pressure can make the foundation material initially stable, reduce the displacement and deformation of the material, and avoid excessive impact on the foundation material by controlling the driving speed and vibration intensity of the roller. The repeated pressure is used to further improve the density and strength of the foundation material. At this time, increasing the driving speed and vibration intensity can ensure that the foundation material reaches the density required by the design. Static pressure is used for final pressure. On the one hand, it can avoid excessive vibration of the foundation material, and on the other hand, it can eliminate wheel marks and cracks on the foundation surface, making the foundation surface flatter and smoother.

[0030] Embodiment 2 See also Figure 1 The present invention provides a technical solution: a construction process for the roadbed and pavement of the settlement section in a municipal road project. The Internet of Things technology is introduced during the construction process of S2, S3, and S4 to perform intelligent monitoring and feedback adjustment, monitor the settlement and deformation of the roadbed in real time, and dynamically adjust the construction parameters such as compaction degree and paving thickness according to the monitoring data to ensure that the roadbed quality is controllable.

[0031] The equipment used for intelligent monitoring and feedback adjustment includes displacement sensors, inclination sensors, stress strain sensors, levels and IoT sensor networks.

[0032] Through the above technical solutions, the displacement sensor uses a laser displacement sensor to measure the displacement of the roadbed surface, which can detect potential settlement or deformation problems. The inclination sensor is used to monitor the change in the inclination angle of the roadbed and evaluate the overall stability and deformation trend of the roadbed. The stress and strain sensor uses a fiber grating sensor to measure the stress and strain state inside the roadbed, which helps to understand the stress condition and deformation degree of the roadbed material. The level is used for high-precision leveling and angle measurement to obtain the elevation change of the roadbed surface. The Internet of Things sensor network is composed of the above multiple sensors and uses the wireless communication technology Lora. It uses its long-distance, large-capacity, low-energy consumption, and its spread spectrum technology with different transmission rates that will not interfere with each other to connect multiple sensors into a network, realize real-time data collection and transmission, and transmit these data to the data center or cloud platform, so that construction personnel can use these data to timely discover and solve problems, avoiding errors caused by lack of real-time monitoring in the actual work process.

[0033] When in use, high modulus asphalt concrete is used as the upper layer, and the lower layer is a microporous elastic asphalt layer. A waterproof barrier is set between the two layers, which enhances the bearing capacity of the road surface, improves drainage efficiency, and reduces settlement caused by water loss. The newly added transverse and longitudinal interlaced drainage pipe network and the highly absorbent resin particles filled therein can quickly collect and discharge road surface seepage water, further reduce the humidity of the loess layer, and reduce the risk of collapse. Through structural optimization, the collapse of loess and foundation deformation are effectively reduced. The loess is modified with nano-silica and nano-alumina, which has lower collapse and higher bearing capacity, can effectively reduce foundation deformation, and lightweight and high-strength fillers are used to reduce the foundation. The deadweight of the roller can improve the overall stability of the foundation. By improving the foundation materials, the original loess collapsibility and its deformation resistance are further improved. The initial pressure can make the foundation materials initially stable, reduce the displacement and deformation of the materials, and avoid excessive impact on the foundation materials by controlling the driving speed and vibration intensity of the roller. The repeated pressure is used to further improve the density and strength of the foundation materials. At this time, increasing the driving speed and vibration intensity can ensure that the foundation materials meet the design density. Static pressure is used for final pressure. On the one hand, it can avoid excessive vibration of the foundation materials, and on the other hand, it can eliminate wheel marks and cracks on the foundation surface, making the foundation surface flatter and smoother. The displacement sensor uses a laser displacement sensor to measure the displacement of the roadbed surface, which can detect potential settlement or deformation problems. The inclination sensor is used to monitor the changes in the inclination angle of the roadbed and evaluate the overall stability and deformation trend of the roadbed. The stress and strain sensor uses a fiber grating sensor to measure the stress and strain state inside the roadbed, which helps to understand the stress condition and deformation degree of the roadbed material. The level is used for high-precision leveling and angle measurement to obtain the elevation changes on the roadbed surface. The IoT sensor network is composed of the above multiple sensors and uses the wireless communication technology Lora. It uses its long-distance, large-capacity, low-energy consumption, and its spread spectrum technology with different transmission rates that will not interfere with each other to connect multiple sensors into a network, realize real-time data collection and transmission, and transmit these data to the data center or cloud platform, so that construction personnel can use these data to promptly discover and solve problems, avoiding errors caused by lack of real-time monitoring in the actual work process.

[0034] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit thereof, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A construction process for subgrade and pavement of a settlement section in a municipal road project, characterized in that: The following steps are involved: S1: Prepare construction materials. According to the design requirements, prepare high modulus asphalt concrete, microporous elastic asphalt layer materials, waterproof insulation materials, gravel, highly absorbent resin particles, nano-modified loess, and lightweight high-strength fillers; S2: Carry out the pavement layer construction, first lay the high modulus asphalt concrete upper layer, then lay the microporous elastic asphalt lower layer on it, and set a waterproof barrier between the two layers. During the construction process, ensure that each layer of material is laid evenly and tightly to avoid gaps and cracks; S3: Carry out gravel layer construction. On the basis of the traditional gravel layer, add a drainage network that is interwoven horizontally and vertically, and fill it with highly absorbent resin particles to ensure that the drainage network is unobstructed and the highly absorbent resin particles are evenly distributed; S4: Carry out foundation treatment, mix nano-modified loess and lightweight high-strength filler in a certain proportion, evenly lay them on the foundation, and use layered dynamic compaction technology for compaction to ensure the close combination of each layer of material and the density of the foundation.

2. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: The thickness of the upper layer of high modulus asphalt concrete is 5-10 cm, and the thickness of the lower layer of microporous elastic asphalt layer is 3-8 cm.

3. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: The waterproof barrier is made of polyethylene film or waterproof coating, and the drainage pipe network is made of polyethylene or polypropylene material, with a diameter of 1-3cm and a spacing of 5-15cm.

4. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: The particle size of the super absorbent resin particles is 0.5-2 mm, and the water absorption rate is 500-2000 g / g.

5. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: Loess is modified with nano-silicon dioxide and nano-alumina to improve its strength and water resistance and reduce its collapsibility. The contents of nano-silicon dioxide and nano-alumina in nano-modified loess are 5-15% and 2-8% respectively.

6. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: Polystyrene foam particles mixed with fly ash and slag powder are used as part of the lightweight and high-strength filler to reduce the deadweight of the foundation. The mass ratio of polystyrene foam particles, fly ash and slag powder is 1:1-3:0.5-2. The layered dynamic compaction technology uses a high-frequency vibratory roller for compaction with a vibration frequency of 25-35Hz and an amplitude of 0.5-1.5mm.

7. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: S4 includes the following steps: S41: Mixing process, including pretreatment, mixing and secondary mixing, crushing and screening loess, removing impurities, ensuring the uniformity of loess particles, putting the pretreated loess, nano silicon dioxide and nano alumina into a mixer in a certain proportion, mixing them fully, mixing polystyrene foam particles, fly ash and slag powder in a certain proportion, crushing and screening, putting nano modified loess and light high strength filler into a mixer in a certain proportion, and performing secondary mixing; S42: Laying process, including base treatment, layered paving and watering for moisture retention. Before paving, clean and level the base of the foundation to ensure that there is no debris or water on the surface of the base. Lay the mixed foundation materials in layers according to the thickness required by the design. After each layer is laid, use a roller for preliminary compaction. During the paving process, water is sprinkled in time to keep moisture, and the watering should be even and appropriate to avoid too much or too little. Drainage facilities should be reserved during the paving process. S43: Compaction process, including initial compaction, recompacting and final compaction. Initial compaction is carried out immediately after paving is completed. During the initial compaction, the travel speed and vibration intensity of the roller are controlled. After the initial compaction is completed, recompacting is carried out, and the vibration intensity and travel times of the roller are appropriately increased. After the recompacting is completed, final compaction is carried out using static compaction.

8. The construction process of subgrade and pavement in a settlement section of a municipal road project according to claim 1, characterized in that: During the construction process of S2, S3, and S4, Internet of Things technology was introduced to conduct intelligent monitoring and feedback adjustment, and real-time monitoring of roadbed settlement and deformation. Based on the monitoring data, construction parameters such as compaction degree and paving thickness were dynamically adjusted to ensure controllable roadbed quality.

9. A construction process for subgrade and pavement in a settlement section of a municipal road project according to claim 8, characterized in that: The equipment used for intelligent monitoring and feedback adjustment includes displacement sensors, inclination sensors, stress strain sensors, levels and IoT sensor networks.

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