List of main technical standards for project construction. Index name technical standard specified value This project adopts value 1 road grade two-way four-lane expressway 2 design speed 80 km/h 80 km/h 3 subgrade width integral subgrade 24.5m, Separated subgrade 12.25m 4 stopping sight distance 1 10m 160 M5 general horizontal curve minimum radius 400m 700m 6 maximum longitudinal slope 5% 4% 7 minimum vertical curve radius (general value) convex 454 load standard highway-Class I 9 design flood frequency bridge/kloc- Other bridges and subgrade 1 1 00 starts from Qigan Village1kloc-0/group (Pengjiayuanzi) in Wuliang Township, Lichuan City, and ends at Tianjiayakou, Chaoyang Village, Moudao Town, Lichuan City. The recommended route is 42.056 kilometers long. There are 6 16m/1 large bridges, 496 1.6m /22 large bridges, 278m /4 medium and small bridges, 0//kloc-0 culverts and 991/kloc-tunnels. The total length of the bridge and tunnel is 28.224km, and the bridge-tunnel ratio is about 67. 1%. There are 3 interchanges, 4 separated interchanges, 28 passages and overpasses. There are 1 service area, 1 management and maintenance area, 1 communication monitoring sub-center, 2 ramp toll stations, 1 main line toll station (half width) and 1 provincial overload control station. Set the connecting line10.05438+0km /2. See table 1-2 for the main engineering quantities.
List of main works: construction mileage per unit quantity of the project km 42.056 subgrade earthwork 1000m 2865.6 asphalt concrete pavement 1000m 798.3 drainage protection works 1000m 209.2 extra-large bridge m/ block 61bridge m/. 2 1 medium bridge m/ block 2778 short tunnel m/ seat 1798.5/6 total length of bridge and tunnel/specific gravity m/% 28224/ 67. 1% interchange 3 separated interchange 4 lane overpass 27 service area 1 management monitoring sub-center/kloc- The engineering geology of the connecting line km 10.06 (1) is complex, and adverse geological phenomena are widely distributed.
The project area is a folded mountainous area in southwest Hubei, which is generally a low mountainous area eroded by structural corrosion, a mountainous area eroded by structural corrosion and a landform area eroded by structural corrosion. According to formation lithology, the route is divided into hard rock section and soft rock section.
Hard rock section: The starting point is Qiyue Mountain (starting point ~ ~K26+400), which is mainly composed of Triassic Badong Formation and Jialingjiang Formation. The rock outcrop is good, and the lithology is mainly carbonate rock, with limestone, dolomite, marl and sandstone mixed with mud shale. The rock is hard, the surface layer is completely weathered to moderately weathered, and the lower part has good integrity. The main rock minerals are calcite, dolomite and argillaceous. The unfavorable geological phenomenon in this section is karst development, which has great influence on subgrade, bridge foundation and tunnel, so countermeasures should be taken.
Soft rock section: from Mopanshan Tunnel to the end point (K26+400~ ~ end point), the lithology is mainly Mesozoic Jurassic Suining Formation, Shangshamiao Formation, Xiashamiao Formation, Xintiangou Formation, Ziliujing Formation and Zhenzhuchong Formation. The lithology is mainly clastic rocks, including sandstone, silty mudstone, mudstone and shale. The rocks are very fragile and highly weathered. The surface layer is completely weathered to moderately weathered rock, with different weathering degrees, developed joints and cracks, and broken rock mass. The main rock mineral components are mainly chronological, feldspar and clay minerals. The unfavorable geological phenomena in this section are rock piles, dangerous rock masses and potentially unstable slopes, and countermeasures should be taken.
(2) The height difference of the route is large, the continuous downhill is long, and the traffic safety problem is outstanding.
Due to the limitation of topographic conditions, the route from Nanping, Lichuan to Chang Gan, Wanzhou has a large topographic gap. The route overcomes the height difference of about 800m, the continuous downhill length is about 36km, and the average longitudinal slope is about 2.2%. From the entrance of Qiyueshan Tunnel in Hubei Province to the end of the project, the continuous downhill length is 23.5km, the height difference is 472m, and the average longitudinal slope is 2.0%. Moreover, this section mostly ends with bridges and tunnels, accounting for 93% of the total weight, and the continuous long longitudinal slope has a particularly prominent impact on traffic safety. Comprehensive measures should be taken in the design to ensure the safety of long downhill driving.
(3) The bridge-tunnel ratio is remarkable, the construction site is narrow and the construction access road is in poor condition.
Bridges and tunnels account for a relatively high proportion in this project. The first half (starting point to Qiyue Mountain) is about 20.2km, and the proportion of bridge and tunnel is 35%. The bridge-tunnel ratio in the second half (Qiyue Mountain to the terminal) is about 23.5km, and the bridge-tunnel ratio in the whole line is 67%. There are Cidonggou Bridge with a span of 150m, Dazhuang Extra-long Tunnel with a length of over 6.5km and Qiyueshan Extra-long Tunnel with extremely complicated geological conditions. This project is located in the middle and low mountainous area, with high mountains and deep valleys, steep terrain and narrow construction site, especially from Qiyue Mountain to the wharf. Lack of construction access road, poor conditions for building access road.
(4) It is difficult to abandon slag in tunnel.
Most of the tunnels in the whole line are concentrated in the section from Qiyueshan to the terminal, and the amount of abandoned slag in the tunnel is large, and the subgrade section is less, so it is impossible to digest a large amount of abandoned slag. Moreover, the topographic and geological conditions make it difficult to select the site of the dump, and the amount of protection works for the dump is large. Route direction: The recommended route plan (K line) starts from Pengjiayuan, Qigan Village, Wuliang Township, Lichuan City, intersects with T-shaped Shanghai-Chongqing Expressway, crosses Yiwan Railway, and sets up the junction of Lichuan West Hub and Shanghai-Chongqing Expressway. The starting station number is K0+000. The route spreads to the northwest, crossing provincial highway 326 on the east side of Maoerdong lime field, setting up Liangwu interchange near the dam mouth, and setting up Lichuan connecting line to connect the planned Lichuan ring road and provincial highway 326 to the east. Set up a tunnel through Lion Mountain, through Group 5 of Lion Mountain Village, cross Qingjiang River 2km downstream of the south exit of Shuilian Cave, and set up Qingjiang Bridge. Take groups 8, 7 and 6 in Panlong Village, groups 9, 3 and 16 in Shangchangcao, Li Shuping and Dayanpo, cross Shentang, group 4 in Shuangshui Village, cross pettitoes dam and Baiyancao, and set up Nanping service area in Mujiatang, cross Kengpo, Yejiawan, Yantangwan, Xintianlong and so on. The line continues northward, 200 meters west of Cao Fang, Zhangjiachang and Nanping Substation. Enter Qiyue Mountain between Qin Family Courtyard and Zhujiayuan Courtyard, and set up Qiyue Mountain Tunnel and Mopanshan Tunnel. Cross the Garden Bay magnetic tunnel and set up a magnetic tunnel bridge. The route goes north into the tunnel, and the Dazhuang extra-long tunnel with a length of about 6.5km is set, and the tunnel exit is at Mazar Beach. The route extends northward along the west side of the valley, passing through Baihu Mountain, Luziping, Yingmen Temple, Baiguoba and Ganzishu, and across the valley (Tianjiayakou) to Chongqing. Hubei and Chongqing are bounded by Tianjiayakou, corresponding to the pile number K43+350 (near the exit of Tianjiayakou Tunnel). The exit of Tianjiayakou Tunnel is tentatively designated as the end of this project, and the end pile number is K43+400. The total length of the recommended route is 42.056km (note: there are two broken links in the K line).
Main control points: Shanghai-Chongqing Expressway, Yiwan Railway, Shuilian Cave, Qingjiang River, Qiyue Mountain, Cidonggou, Mazatan, Luziping and Tianjiayakou.
Full-line control works: LiXixi Hub Interchange, Wuliang Interchange, Qingjiang Bridge, Nanping Interchange, Qiyueshan Tunnel, Cidonggou Bridge and Dazhuang Tunnel.
Main rivers: Qingjiang River, Plum Water and Longju River.
Main highways: Shanghai-Chongqing Expressway, G3 18 National Highway and S326 Provincial Highway.
Main railway: Yiwan Railway. The key and difficult projects of this project mainly include Qingjiang Bridge, Cidonggou Bridge, Qiyueshan Tunnel and Dazhuang Tunnel.
1, Qingjiang Bridge
The bridge site is located in Lichuan City. The starting point of the bridge is connected with the exit of Aoercao Tunnel, and the end point is connected with the entrance of Chayuan Tunnel, crossing the Qingjiang River at the junction of Shishi Village and Lizi Village in Wuliang Township. The bridge site area belongs to the Zhongshan area with low degree of structural erosion and dissolution. The highest elevation is between1.270-1.300m, and the relative height difference is about 200m. The mountain extends linearly in a circular shape, and the mountain is steep, with an average slope of about 35, and the slopes on both sides of the valley reach more than 50. The riverbed between mountains is narrow, the valley is about 100m wide, some bedrock is exposed, and the abutments at both ends are located on the slope. The exposed strata in the bridge site area are mainly Triassic Jialingjiang Formation (T 1j) and local Quaternary eluvial layer (Q4el+dl).
The main bridge of Qingjiang Bridge is a continuous rigid frame scheme with 65+ 120+65m prestressed concrete cantilever box girder, with a main span of 120m and a side span of 65m. The main pier is a box-shaped hollow pier, and the pier top is consolidated with the box girder. 1×30m and 3×30m prestressed concrete T-beams are used for the approach bridges at the front and rear banks.
2. Cidonggou Bridge
The bridge site is located in Lichuan City. The starting point of the bridge is connected with the exit of Mopanshan Tunnel, and the end point is connected with the entrance of Guihuaping Tunnel. Pass through the magnetic cave ditch in Li Shuping, Wanli Village, Moudao Town. The bridge site area belongs to the Zhongshan terrain with low degree of structural erosion, with a peak elevation of about 1 220 m and a relative height difference of about 200m m. The mountain extends in a sharp line with a steep slope, with an average slope of about 35 and a local slope greater than 45. The riverbed in the mountains is narrow and about 50 meters wide. Vegetation is well developed, local bedrock is directly exposed, and most of the surface layer is covered with debris. There are houses, farmland and cultivated land nearby. The exposed strata in the bridge site area are mainly Triassic Xujiahe Formation (T3xj) sandstone, Jurassic Zhenzhuchong Formation (J 1z) fine-grained clastic sandstone and Quaternary eluvial material (Q4al+pl).
Cidonggou Bridge has no navigation requirements. In order to adapt to the terrain conditions and meet the requirements of crossing, the main bridge of Cidonggou Bridge is a continuous rigid frame with 85+ 150+85m prestressed concrete cantilever box girder, and the main pier is a box-shaped hollow pier. Pier top and box girder are consolidated, and the height of main pier is 123~ 130m. The upper structure of the approach bridge adopts 40m prestressed concrete continuous T-beam.
3. Qiyueshan Tunnel
Qiyueshan Tunnel is a two-way four-lane separated tunnel located in Qiyueshan, Lichuan City, Hubei Province. The tunnel is about 3382 meters long (right width), and the entrance and exit of the tunnel adopt stepped holes. The underlying bedrock is Permian limestone and siliceous limestone, sandwiched with coal seam, shale and Triassic limestone, and locally sandwiched with thin shale. The tunnel passes through Qiyueshan anticline. Qiyueshan anticline has asymmetric wings and is mainly composed of limestone mixed with shale and coal seam. The exposed stratum at the core of anticline is medium-thick layered limestone of Changxing Formation, and its two wings are in contact with faults at the core of anticline, which is a karst pole development area. There are two faults in the tunnel body of the proposed tunnel site, and karst development is the main feature in the fault zone, and there may be large karst caves, which have a great influence on the tunnel construction.
4. Dazhuang Tunnel
Dazhuang Tunnel is a two-way four-lane separated tunnel, located in Shangba Village, Moudao Town, Lichuan City, Hubei Province. The length of the tunnel is 6570m (right), and the entrance and exit of the tunnel adopts end wall portal. The bedrock is purplish red mudstone (J2s) of Middle Jurassic Shaximiao Formation, and sandstone and timely sandstone (J2S) of Middle Jurassic Shaximiao Formation. The tunnel site is located in the southeast wing of Matouchang syncline, which is mainly monoclinic stratum with relatively slow dip angle. No fault crossing the stratum was found in the tunnel area. The main unfavorable geological bodies in the tunnel area are dangerous rock mass and collapse accumulation body, among which the dangerous rock mass and collapse accumulation body above the tunnel entrance and exit have great influence on the tunnel. According to the work feasibility report, combined with the distribution of towns along the line, road network planning, traffic flow distribution and social and economic development, and after fully considering the road grade, traffic volume distribution, highway toll and topographical and geological conditions, this project * * * sets up three interchanges: Lixian Hub Interchange, Wuliang Hub Interchange and Nanping Hub Interchange.
1, Lichuan West Hub Interchange
The starting point of the project is flagpole village 1 1 group (Pengjiayuan) in Wuliang Township and T-junction of G50 Shanghai-Chongqing Expressway, and a traffic flow conversion hub is set up to communicate Lichuan East, Enshi and Zhongxian. Chongqing Enshi-Wanzhou is the main direction, the ramp design speed is 60 km/h, and the subgrade is designed according to the separated main line, and the subgrade width is12.25m; ; The planning from Dianjiang in Chongqing to Wanzhou in Chongqing is the secondary direction. The design speed of ramp is 40~50Km/h, and the width of subgrade is 8.5m and 10.5m according to the traffic volume and length. ..
2, cool fog intercommunication
Wuliang Interchange is located in Qigan Village, Wuliang Township, Lichuan City. It is planned to adopt the single-horn interchange scheme, and set the Lichuan connecting line to connect S326 and Lichuan Ring Road, and connect the west area of Lichuan City and Wuliang District. The design standard of the connecting line is a first-class highway, with a design speed of 60km/h, a subgrade width of 20m and a length of about 3. 1km.
3. Nanping overpass
Nanping Interchange is located in Ganyan Village, Nanping Township, Lichuan City, connecting G3 18, providing services for vehicles in Nanping Township, Baiyang Town and Moudao Town. In order to improve the travel in Moudao Town and avoid crossing the high-altitude section of Qiyue Mountain, the connecting line from Nanping Interchange to Moudao Town is set, that is, the national highway 3 18 Qiyue Mountain diversion section. The diverted section starts from Walnut Tree in Ganyantang, Nanping Town and ends at Yanziping Reservoir in Moudao Town. The length of the reconstructed section is 6.93km, and it is planned to be built according to the standard of secondary highway, with a design speed of 60 km/h.