CN101967786B - Airfield pavement structure with box-type shock-isolation foundation - Google Patents

Abstract

The present invention is an airport pavement structure of a box-type seismic isolation foundation, which is composed of a surface layer and a base layer: the surface layer is a concrete pavement, which directly bears the load of the aircraft, and is located on the top; the base layer is a box-type seismic isolation foundation, which plays a load-bearing role. The position is below; the box-type seismic isolation foundation is placed on the foundation, and the concrete pavement is placed on the box-type seismic isolation foundation. The concrete pavement is made of cement and asphalt concrete commonly used in airport pavements. The box-type seismic isolation foundation consists of a roof, an outer wall, a transverse wall, a longitudinal wall, a bottom plate, and a seismic isolation support. The bottom plate is set on the foundation, and the outer wall, transverse wall and vertical wall are divided into upper and lower parts. seat connected. The present invention is a new type of airport pavement structure suitable for complex foundations such as mountainous areas and soft soils. Can maintain normal function.

Description

A box-type seismic isolation foundation airport pavement structure

(1) Technical field:

The invention relates to an airport pavement structure, in particular to a box-type seismic isolation foundation airport pavement structure, which belongs to the technical field of basic structures and materials in road traffic engineering.

(2) Background technology

With the rapid development of my country's air transport industry, some coastal cities have built airports on weak foundations, such as Zhuhai Airport. The soil layers in the field are staggered and highly variable. bit close to the surface. With the vigorous development of regional aircraft by the country, regional airlines have also begun to build their route network, mainly concentrated in the southwest, northwest, Xinjiang and other places with complex terrain, landform and geological background conditions, such as Kunming Xiaoshao Airport, where karst is developed, Caves and funnels are dotted all over. At present, the development direction of airport construction sites in my country and internationally is "uphill and downhill", and airport construction in these areas faces a series of special problems: (1) Special ground handling problems. Weak foundations generally cannot meet the high standard requirements for foundation deformation of airport runways, so large-area and deep foundation treatment is required for the foundation; (2) High filling problems for airport construction in mountainous areas. The flight areas of airports in mountainous areas in the west generally require high filling and deep excavation, and the amount of earth and stone works is huge. For example, the maximum filling height of Lincang Airport reaches 52m, and that of Jiuzhai Huanglong Airport in Sichuan even reaches 100 meters. The foundation and filling stability problems are prominent, and the new The tectonic activities are relatively frequent, the stability of the regional crust is poor, and the seismic safety of the site is low. (3) The problem of sea airport construction. The physical and mechanical indexes of the soil in the sea are poor, and due to the action of seawater, the structural force is complicated. Therefore, as one of the most important components of airport construction, the engineering quality of the roadway engineering has received more and more attention. Due to the complexity of the foundation, some technical problems that need to be solved have gradually been exposed in engineering practice, which has become a research topic. One of the hot issues.

For the construction of airport runways on complex foundations, controlling the settlement and uneven settlement of the foundation is the core issue of airport construction. At present, most of the built airports only use foundation treatment to control settlement. For example, Zhuhai Airport uses methods such as dynamic compaction, drainage consolidation, and compacted sand piles to treat the 30m deep foundation, and achieved good results. Some newly built airports in my country in recent years have put forward higher requirements for the post-construction settlement and differential settlement of the foundation. Generally, two 5cm are used as the standard: the post-construction settlement is less than 5cm, and the settlement difference of the radius of the 50m deflection basin is less than 5cm. That is, the differential settlement is less than 1‰, and for airports with good geological conditions in inland areas, these settlement control indicators can basically be met. However, for airports built on foundations with complex engineering geology, such as Shanghai Pudong International Airport (Phase I), Zhuhai Airport, Ningbo Airport, and Sichuan Panzhihua Airport, it is relatively difficult to meet these strict settlement control indicators during the operation period. Difficult, in order to meet this standard requires large-scale foundation treatment, and from engineering examples, the settlement after several years of operation of the airport mostly exceeds the design settlement. In the design of industrial and civil buildings, the box foundation is a common foundation for buildings. It has the advantages of large overall rigidity, strong ability to adjust uneven settlement of the foundation, good seismic performance and full use of internal space. It is widely used in high-rise buildings and soft soils. And other areas with complex engineering geology are also being used more and more in marine engineering, such as as the foundation of breakwaters, cofferdams and revetment structures.

Therefore, it can be seen that as long as the design is reasonable and the pavement structure is improved on the basis of foundation treatment, the foundation settlement and differential settlement can be better controlled, and the anti-seismic performance of the airport runway can be improved at the same time, making aircraft takeoff and landing safer.

(3) Contents of the invention

1. Purpose of the invention:

The purpose of the present invention is to provide a box-type seismic isolation foundation airport pavement structure, which has a strong ability to adjust the uneven settlement of the foundation, reduces the difficulty of foundation treatment, and the seismic isolation structure enables the airport pavement to remain normal under the action of earthquakes It is a new type of airport pavement structure suitable for complex foundations such as mountainous areas and soft soils.

2. Technical solution:

The present invention is a box-type earthquake-isolation foundation airport pavement structure, the pavement structure is divided into two levels: the surface layer and the base layer: the surface layer is a concrete pavement, which directly bears the load of the aircraft, and the position is on the top; the base layer is a box-type shock-isolation The foundation mainly plays the role of load-bearing (diffusion load), and its position is below it; the base layer, that is, the box-type seismic isolation foundation, is placed on the foundation, and the surface layer, that is, the concrete pavement, is placed on the box-type seismic-isolation foundation.

The concrete pavement can be cement concrete or asphalt concrete commonly used in airport pavements, and should have good temperature stability, impermeable, wear-resistant, anti-slip and smooth surface. In addition, due to the addition of a box foundation to the pavement structure, it is convenient to set up a drainage structure in the foundation roof and confined space (as shown in Figure 2), so the concrete pavement can also use high water-permeable concrete materials such as permeable concrete. The length of the concrete pavement is 800-3000 meters, the width is 30-80 meters, and the thickness is 200-600 millimeters; the specific size depends on the airport level and its location altitude, temperature and other factors.

The box-type seismic isolation foundation is composed of a roof, an outer wall, a transverse wall, a longitudinal wall, a bottom plate, and a seismic isolation support (as shown in FIG. 3 ). The position connection relationship between them is: the base plate is set on the foundation, the outer wall, transverse wall and longitudinal wall are divided into upper and lower parts, the lower half is poured with the base plate as a whole, and the upper half is poured with the roof as a whole , The two parts are connected by a seismic isolation support, and the outer wall should be closed after the isolation support is installed to prevent the surrounding foundation soil from flowing into the room. The length and width of the box-type seismic isolation foundation are respectively consistent with the length and width of the concrete pavement. The length is suitable for 800-3000 meters, and the width is suitable for 30-80 meters. The height is 1/10 to 1/15 of the width of the concrete pavement, and 3 to 6 meters is suitable. The specific size depends on factors such as the bearing capacity of the foundation, settlement control requirements, and the load on the airport.

The roof is made of reinforced concrete, connected to the concrete pavement at the top, and connected to the box-shaped foundation wall at the bottom. According to the different properties of the materials used on the pavement, the roof can be equipped with drainage ditches (as shown in Figure 2). The drainage ditches should be set up with 1 to 2 channels in each room. Rice is suitable. The length and width of the roof are respectively consistent with the length and width of the concrete pavement. The length is suitable for 800-3000 meters, the width is suitable for 30-80 meters, and the thickness is suitable for 300-800 mm;

The exterior wall is made of reinforced concrete, and its length and width are respectively consistent with the length and width of the concrete pavement. The length is 800-3000 meters and the width is 30-80 meters. 1/15, 3 to 6 meters is suitable, and the thickness is 300 to 600 mm. The specific size needs to be determined according to the bearing capacity of the foundation, settlement control requirements, and the load on the airport.

The transverse wall is made of reinforced concrete (as shown in Figure 4), the length is consistent with the width of the concrete pavement, and is suitable for 30-80 meters, and the height is 1/10-1/15 of the width of the concrete pavement, which is 3-6 meters Appropriate, the isolation support is divided into upper and lower parts, the thickness is 200-500 mm, and the distance between each horizontal wall is 8-12 meters. The specific size depends on the foundation bearing capacity, settlement control requirements, and the load on the airport. factors.

The longitudinal wall is made of reinforced concrete (as shown in Figure 5), the length is consistent with the length of the concrete pavement, and is suitable for 800-3000 meters, and the height is 1/10-1/15 of the width of the concrete pavement, which is 3-6 meters Appropriate, the isolation support is divided into upper and lower parts, the thickness of which is 200-500 mm is suitable, and the distance between each longitudinal wall is 4-8 meters. factors.

The base plate is made of reinforced concrete, with a length and width of 1 to 3 meters along the edge of the outer wall, and a thickness of 300 to 800 mm;

The seismic isolation support can choose lead core laminated rubber support, friction pendulum support, etc. This type of support has a wide range of horizontal stiffness and damping performance, a small support height, and a large load-bearing capacity, which can effectively reduce vibration. The torsion effect of the small structure, the shock isolation effect is not affected by temperature and the installation is simple. Dampers such as friction dampers and magneto-rheological dampers can also be selected. This type of seismic isolation component has the advantages of stable performance under repeated loads and variable damping force, but the installation method is usually more complicated and the cost is higher. The connectors of the isolation support usually include connecting steel plates, embedded steel plates, high-strength bolts, and embedded anchor rods or anchor bars. The pre-embedded anchor rod or anchor bar is connected with the pre-embedded steel plate and fixed in the wall, the connecting steel plate is connected with the inside of the isolation support with bolts, and the connecting steel plate and the pre-embedded steel plate are connected with high-strength bolts. Set up a seismic isolation support every 1 to 3 meters along the outer wall, transverse wall, and vertical wall (as shown in Figure 6). The outer wall should be closed after the installation of the seismic isolation bearing to prevent the surrounding foundation soil from flowing into the room (as shown in Figure 7). .

The box-type seismic isolation foundation airport pavement structure introduces the box-type seismic isolation foundation as the base layer into the ordinary airport pavement structure, which provides stable support for the concrete pavement layer. The box-type seismic isolation foundation can be considered as a rigid foundation with good integrity. When the foundation soil is uneven, it can play a good role in adjusting uneven settlement. The internal vertical and horizontal walls of the box-type seismic isolation foundation are cross-arranged to support each other. During an earthquake, the shaking earth pressure can be transmitted to the opposite side of the soil through the inner wall, thus playing a certain role in earthquake resistance. The introduction of seismic isolation bearings into the wall reduces the overall rigidity of the box foundation to a certain extent, but enables the airport pavement to maintain its normal function under the action of moderate and large earthquakes. The seismic isolation bearing has a variable horizontal stiffness, and it has sufficient horizontal stiffness under the action of the plane's horizontal load and small earthquakes. During moderate and large earthquakes, the horizontal stiffness of the seismic isolation bearing becomes smaller, making the natural vibration period of the isolation structure It becomes longer, which "blocks" part of the seismic energy and reduces the seismic energy input into the pavement layer. The seismic isolation support enters the plastic stage before the pavement layer, and the seismic energy is mainly consumed by its plastic deformation and damping. Therefore, the pavement layer can basically maintain elastic deformation without serious damage, maintaining the normal use function of the airport. The back road surface and wall repair work is simple, and when replacing the seismic isolation support, you only need to unscrew the bolts, and the seismic isolation support and connecting steel plates can be taken out. The replacement operation is also very simple.

3. Advantages and effects:

(1) Adjust the uneven settlement of the foundation to reduce the difficulty of complex foundation treatment. The overall performance of the box-type seismic isolation foundation is good, and the ability to adjust the uneven settlement of the foundation is strong, which reduces the control index of foundation settlement and differential settlement, thereby reducing the difficulty of foundation treatment, reducing the volume of base treatment and excavation and filling;

(2) High security. The box-type seismic isolation foundation itself has good seismic capacity, can adapt to poorly stable foundations and fillings in the construction of mountainous airports, and can significantly reduce earthquake damage caused by weak foundation liquefaction and other issues. The wall is equipped with shock-isolation bearings to release the temperature stress, making the pavement structure safer and more stable. It has a shock-isolation effect during a major earthquake and maintains the normal use of the airport runway;

(3) The underground space can be fully utilized to realize the multifunctionality of the runway. In winter, the runway is troubled by rain, snow and frost. The confined space can be used for temperature control, and a large area of temperature-controlled snowmelt can be used on the runway, so that the runway can be reused quickly and economic losses can be reduced. Drainage structures can also be set on the foundation roof and the confined space to quickly drain the rainwater on the surface of the pavement and improve the safety of aircraft take-off and landing. For busy airports, the underground space can be used to set up traffic service lanes to make the traffic in the flight area convenient.

(4) Description of drawings

Figure 1 Schematic diagram of the airport pavement structure of the box-type seismic isolation foundation

Figure 2 Schematic diagram of roof drainage ditch structure

Fig. 3 Simplified plan view of box-type seismic isolation foundation (a) top view; (b) front view; (c) left view.

Figure 4 Schematic diagram of the longitudinal section of the airport pavement structure of the box-type seismic isolation foundation

Figure 5 Schematic diagram of the cross-section of the airport pavement structure of the box-type seismic isolation foundation

Figure 6 Schematic diagram of the structure of the horizontal wall (longitudinal wall) seismic isolation support

Figure 7 Schematic diagram of the structure of the external wall isolation support

The symbols in the figure are explained as follows:

1 concrete pavement; 2 roof; 3 exterior wall; 4 longitudinal wall;

5 horizontal wall; 6 bottom plate; 7 seismic isolation bearing; 8 drainage ditch;

9 Connecting steel plates; 10 Embedded steel plates; 11 High-strength bolts; 12 Embedded anchor rods or anchor bars.

(5) Specific implementation methods

As shown in Fig. 1, a kind of box-type seismic isolation foundation airport pavement structure of the present invention, this pavement structure is divided into surface layer and base layer two levels: surface layer is concrete pavement 1; Base layer is box type seismic isolation foundation, It is composed of top plate 2, outer wall 3, longitudinal wall 4, transverse wall 5, bottom plate 6 and shock-isolation support 7. The box-type seismic isolation foundation is placed on the foundation, and the concrete pavement 1 is placed on the box-type seismic isolation foundation.

As shown in Figure 2, the concrete pavement 1 can be cement concrete or asphalt concrete commonly used in airport pavements, and should have good temperature stability, impermeable, wear-resistant, anti-slip and smooth surface. In addition, since the pavement structure is equipped with a box-shaped foundation, it is convenient to set up a drainage structure in the foundation roof 2 and the confined space, so the concrete pavement 1 can also use high water-permeable concrete materials such as permeable concrete. The concrete pavement 1 has a length of 1500 meters, a width of 40 meters and a thickness of 250 millimeters.

As shown in Figure 3 (a), (b) and (c), the box-type seismic isolation foundation consists of a roof 2, an outer wall 3, a longitudinal wall 4, a transverse wall 5, a bottom plate 6, and an isolation support 7. The bottom plate 6 is set on the foundation, the outer wall 3, the transverse wall 5 and the vertical wall 4 are divided into two parts, the upper part and the lower part. They are connected by seismic isolation support 7, wherein the outer wall 3 should be closed after the seismic isolation support 7 is installed to prevent the surrounding foundation soil from flowing into the room. The length and width of the box-type seismic isolation foundation are the same as the length and width of the concrete pavement 1, with a length of 1500 meters and a width of 40 meters. The height is 4 meters.

The roof 2 is formed by pouring reinforced concrete, the upper part is connected with the concrete pavement 1, and the lower part is connected with the box-shaped foundation wall. According to the different performances of the materials used on the pavement, the top plate can be provided with drainage ditches 8 (as shown in Figure 2), and each room of the drainage ditches 8 is provided with one road, 4 meters apart in the horizontal direction, and 10 meters apart in the vertical direction. The length and width of the roof 2 are respectively consistent with the length and width of the concrete pavement, the length is 1500 meters, the width is 40 meters, and the thickness is 400 millimeters;

The outer wall 3 is made of reinforced concrete, and its length and width are respectively consistent with the length and width of the concrete pavement 1. The length is 1500 meters, the width is 40 meters, the height is 4 meters, and the thickness is 300 millimeters.

As shown in Figure 4, the transverse wall 5 is made of reinforced concrete, the length is 40 meters, and the height is 4 meters, which is consistent with the width of the concrete pavement 1. It is divided into upper and lower parts by the isolation support, and the thickness is 200. mm, each horizontal wall is 10 meters apart.

As shown in Figure 5, the longitudinal wall 4 is made of reinforced concrete, the length is the same as that of the concrete pavement 1, which is 1500 meters, and the height is 4 meters. It is divided into upper and lower parts by the seismic isolation support 7, and the thickness is 200 mm, and each horizontal wall is 5 meters apart.

The bottom plate 6 is made of reinforced concrete, and its length and width are 2 meters outside along the edge of the outer wall respectively. The length is 1504 meters, the width is 44 meters, and the thickness is 400 millimeters.

The shock-isolation support 7 can be selected from a lead core laminated rubber support, a friction pendulum support, etc., and can also select dampers such as a friction damper and a magneto-rheological damper. The friction pendulum support is selected here; the connectors of the seismic isolation support 7 usually include connecting steel plates 9, embedded steel plates 10, high-strength bolts 11, and embedded anchor rods or anchor bars 12, etc. The pre-embedded anchor rod or anchor bar 12 is connected with the pre-embedded steel plate 10, and fixed in the wall, the connecting steel plate 9 is connected with the interior of the shock-isolation support 7 with bolts, and the connecting steel plate 9 and the pre-embedded steel plate 10 are connected with high-strength bolts 11 connected. Seismic isolation bearings 7 are provided every 2 meters along the outer walls 3, transverse walls 5, and longitudinal walls 4, as shown in Figure 6, wherein the outer walls should be closed after the seismic isolation bearings are installed to prevent the surrounding foundation soil from flowing into the room, as shown in Figure 6. Figure 7 shows.

Claims (9)

1. A box-type seismic isolation foundation airport pavement structure is characterized in that: the pavement structure is divided into two layers of surface layer and base layer: the surface layer is a concrete pavement, directly bears the aircraft load, and the position is on the top; the base layer is a box The base layer, namely the box-type seismic isolation foundation, is placed on the foundation, and the surface layer, that is, the concrete pavement, is placed on the box-type seismic-isolation foundation; The concrete pavement is cement concrete or asphalt concrete commonly used in airport pavement, which has good temperature stability, impermeable, wear-resistant, anti-slip and smooth surface; The box-type seismic isolation foundation is composed of a roof, an outer wall, a transverse wall, a longitudinal wall, a bottom plate, and a seismic isolation support. It is divided into upper and lower parts, the lower part is poured with the bottom plate as a whole, the upper part is poured with the roof as a whole, and the two parts are connected by seismic isolation bearings; The concrete pavement is connected with the box-type seismic isolation foundation wall; the outer wall is made of reinforced concrete, and the outer wall should be closed after the isolation support is installed to prevent the surrounding foundation soil from flowing into the room; the transverse wall is made of reinforced concrete The vertical wall is made of reinforced concrete, which is divided into upper and lower parts by the seismic isolation support, and the bottom plate is made of reinforced concrete; The shock bearing is one of lead core laminated rubber bearings, friction pendulum bearings, friction dampers, and magneto-rheological dampers. Buried anchor rods and anchor bars, pre-embedded anchor rods and anchor bars are connected to the pre-embedded steel plates and fixed in the wall, the connecting steel plates are connected to the inside of the shock-isolation support with bolts, and the connecting steel plates and the pre-embedded steel plates are connected with high-strength steel plates. bolted together. 2. A box-type seismic isolation foundation airport pavement structure according to claim 1, characterized in that: the concrete pavement has a length of 800-3000 meters, a width of 30-80 meters, and a thickness of 200-600 mm. 3. A box-type seismic isolation foundation airport pavement structure according to claim 1, characterized in that: the box-type seismic isolation foundation has a length of 800 to 3000 meters, a width of 30 to 80 meters, and a height of 3 to 6 meters. rice. 4. A box-type seismic isolation foundation airport pavement structure according to claim 1, characterized in that: the length of the roof is 800-3000 meters, the width is 30-80 meters, and the thickness is 300-800 mm; the roof is set There are 1 to 2 drains for each room, the horizontal drains are 4 to 8 meters apart in the horizontal direction, and the vertical drains are 8 to 12 meters apart in the vertical direction. 5. A box-type seismic isolation foundation airport pavement structure according to claim 1, characterized in that: the length of the outer wall is 800-3000 meters, the width is 30-80 meters, and the height is 3-6 meters. The thickness is 300-600mm. 6. A box-type seismic isolation foundation airport pavement structure according to claim 1, characterized in that: the length of the transverse wall is 30-80 meters, the height is 3-6 meters, and the thickness is 200-500 mm. The distance between the horizontal walls is 8-12 meters. 7. A box-type seismic isolation foundation airport pavement structure according to claim 1, characterized in that: the length of the longitudinal wall is 800 to 3000 meters, the height is 3 to 6 meters, and the thickness is 200 to 500 mm. The vertical walls are 4 to 8 meters apart. 8. A box-type seismic-isolation foundation airport pavement structure according to claim 1, characterized in that: the length and width of the bottom plate are respectively 1-3 meters along the edge of the outer wall, and the thickness is 300-800 mm. 9. A box-type seismic-isolation foundation airport pavement structure according to claim 1, characterized in that: the seismic-isolation bearings are provided every 1-3 meters along the outer wall, transverse wall, and vertical wall.