Qiandao Lake Bridge

Qiandaohu bridge is 1258 meters long, east-west, with a deck width of 18 meters. The main bridge is 928 meters long, and the two-way sidewalks are 1.5 meters wide. Heightening the sidewalks and reserving optical cable holes in the sidewalks leave a good hand for the digital transformation of the reservoir area. It is like a magnificent rainbow across the lake, which is the crystallization of the wisdom and sweat of bridge builders.

Standing on the South Rail in the middle of the bridge, looking southeast, the lake is clear, and the lake is full of smoke and blue waves. Its secluded blue waves wash our impetuous mind all the time, away from the hustle and bustle of the city. Here, our mind naturally returns to peace. The body and mind are relaxed at the moment. At this time, the sun has crossed the east mountain top and looked at us gently over the lake. The golden sun sprinkles on the lake, which is like putting gorgeous silk clothes on the lake. The morning wind blows, and the waves are sparkling and ripple layer upon layer. There are islands in the distance, with mountains and rivers, such as bright pearls inlaid on jadeite. Far sighted, distant mountains like Dai, like a heavy, not decorated splash ink painting, it is refreshing.

Qiandao Lake Bridge

Qiandaohu bridge, located on Qiandaohu Lake, is a passage across the lake in Hangzhou City, Zhejiang Province, China. It is a key project in the construction of highway network of Chunan County's transportation planning, which "forms a ring inside and dredges the mouth outside".

The construction of Qiandaohu bridge started on September 28, 2002;

The closure project of the main bridge was completed on August 16, 2005, and the whole bridge was connected;

It was put into operation on September 20, 2005.

Qiandaohu bridge starts from Yangguang road in the west, crosses Qiandaohu waterway in the East and ends at Jixian road in the East. The total length of the line is 1258 meters, and the main bridge is 928 meters long. The bridge deck is a two-way four car first-class highway with a design speed of 40 km / h. The total investment of the project is 138 million yuan.

Construction process

On September 5, 2001, Zhejiang Provincial Department of Transportation approved the feasibility study report of Qiandaohu bridge project in Chun'an County by the people's Government of Chun'an County, and agreed to build Qiandaohu bridge.

On April 12, 2002, Zhejiang Provincial Department of Transportation approved the preliminary design of Qiandaohu bridge project in Chun'an County, Zhejiang Province by Chun'an County Government, and approved the project design scheme; on September 28, the construction of Qiandaohu bridge was started, and the foundation laying ceremony was held.

On February 18, 2003, the first pile foundation of Qiandaohu bridge was drilled; on April 20, the bridge was drilled. On October 7, the construction of the first bearing platform of Qiandaohu bridge was completed.

On February 16, 2004, the construction of the first V-shaped Pier of Qiandaohu bridge was completed; on November 28, the construction of the lower part of Qiandaohu bridge was completed.

On August 16, 2005, the closure project of the main bridge of Qiandaohu bridge was completed, and the whole bridge was connected;

On September 15, the Qiandao Lake Bridge project was completed;

On September 18, Qiandaohu bridge passed the acceptance of Hangzhou traffic engineering quality and safety supervision station;

On September 20, Qiandao Lake Bridge was opened to traffic.

Bridge location

Qiandao Lake Bridge is located in the northeast of Qiandao Lake central area, 3km north of Chun'an County, Hangzhou City, Zhejiang Province, China. It starts from Yangguang road in the west, crosses Qiandao Lake waterway in the East and ends at Jixian road in the East. The route of the bridge is chun'an-kaihua expressway.

Architectural design

building structure

Overall layout

Qiandaohu bridge is composed of main bridge, approach bridge, V-shaped pier and interchange ramp, and the main bridge section is arranged from southeast to northwest.

 

Design concept

Qiandaohu bridge adopts the design scheme of V-shaped pier continuous rigid frame bridge; the multi span V-shaped pier continuous rigid frame bridge has the advantages of novel and light structure, beautiful and symmetrical appearance, such as the fusion of the wings of birds and the surrounding landscape, which is the organic combination of strength and beauty, adding beauty to people's enjoyment.

 

Design features

The main bridge of Qiandaohu bridge adopts the design scheme of prestressed concrete continuous rigid frame with multi hole long connected V-Shaped Piers; the main beam adopts single box single chamber inclined web section, and the box girder adopts longitudinal, transverse and vertical prestressed system; the longitudinal prestressed steel strand of box girder adopts three kinds of steel strand, and the transverse prestressed steel strand of box girder roof adopts one kind of steel strand. The transition from the top of inclined leg of V-shaped pier to the bottom of closure section is based on circular curve. The main pier adopts high pile cap bored pile foundation, each pier is set with four concrete-filled steel tubular rock socketed piles, underwater C35 concrete is used, V-shaped pier slant leg is plate reinforced concrete structure, slant leg axis and pier center line are consolidated below. The pier base is an ordinary reinforced concrete structure.

 

Design parameters

Qiandaohu bridge is 1258.1 meters long and 18 meters wide, of which the main bridge is 928 meters long and (70 + 7 × 105 + 70 + 40) meters long, and the approach bridge is 330 meters long and (5 × 60) meters long. The box girder on the top of V-shaped pier is 4.2 meters high and 29 meters long, and the closure section and side span straight section are 2.7 meters high; the top plate of main girder box girder is 18.0 meters wide, the two wing cantilever is 4.15 meters long, the top plate of the whole bridge is 0.25 meters thick (at the center line of box girder), the web plate is 0.5 meters thick, and the bottom plate is 0.5 meters thick from the inclined leg to 0.25 meters thick at the closure section according to the circular curve; there are 19 transverse partitions in the box girder, all 1.0 meters thick. The intersection angle between the axis of V-shaped pier diagonal leg and the pier center line is 45 degrees, the length of diagonal leg is 13.8 to 16.5m, the transverse width is 7.5m, the thickness of diagonal leg root is 2.0m, and the thickness of the consolidation part with box girder is 1.03 to 1.21m. The pier base is 5.328m along the bridge, 7.8m wide and 4.0m high across the bridge; the steel pipe wall thickness of No.1, No.2, No.7 and No.8 piers is 24mm, and the steel pipe wall thickness of No.3 to No.6 piers is 22mm.

 

Operation

Fare system

As of October 2019, no toll system will be implemented for Qiandaohu bridge.

 

Construction achievements

Technical problems

construction technique

The main construction technologies of Qiandaohu bridge are as follows:

1. Super long multi span V-shaped Pier Rigid Frame;

2. The application of concrete filled steel tubular pile;

3. Deep water pile planting technology;

4. Composite floating bored pile construction platform;

5. V-shaped pier construction on deep water flexible foundation;

6. Construction monitoring of long connected multi span V-shaped pier rigid frame beam.

 

technological innovation

The main technical innovations of Qiandaohu bridge are as follows:

1. The use of long-span multi-span prestressed concrete continuous rigid frame bridge with V-shaped piers is not only the distinct engineering characteristics of Qiandaohu bridge, but also one of the technical innovations of the bridge. In order to realize the main design intention of the bridge, combined with the natural and engineering conditions of the bridge site, the large-scale selection of concrete-filled steel tubular piles in the bridge foundation design, and the supporting development of deep-water pile planting technology, make the use of concrete-filled steel tubular pile foundation form a complete set of Engineering Technology from design to construction; the successful use of this technology enriches and widens the design and construction of bridge foundation, Especially for solving the engineering problem of how to economically recover and make full use of steel casing through the combination of permanent and temporary in deep water high pile cap bored pile foundation, it has innovative practical significance and great practical reference value.

2. The development and application of the combined floating bored pile construction platform is another major technical innovation of Qiandaohu bridge; the floating platform relies on the buoyancy of water to support the platform structure and the weight of the construction equipment on it, which is affected by the change of water level and the flow velocity Even in the reservoir area, the fixed platform can not meet the requirements of long-term stable positioning of the steel casing directly through the anchorage. The lower end of the steel casing of the bored pile must be rigidly embedded in the riverbed, but if the top of the steel casing is directly connected with the platform, the floating body will have a large swing In the past, the floating platform used in bridge construction is mostly used to strengthen the anchorage and frequently adjust the tightness of the anchor rope to ensure the position of the top of the pile casing; this method has large workload, high requirements and certain risks, and it is possible for the construction with fewer piles, but it is not suitable as a mature technology In view of the above problems, Qiandaohu bridge creatively proposed to separate the positioning of steel casing from the floating platform, Through the special positioning device at the top of the casing, the plane position of the lifting wire rope of the drill bit of the percussive reverse circulation drilling rig is always fixed in the center of the top of the casing, which not only avoids the influence of the floating body on the casing during the conventional shaking, but also overcomes the influence of the drilling machine along with the floating body on the hole forming quality. The improved platform technology and process are reliable, Because there is a proper gap between the floating body and the casing, it is not necessary to adjust the anchor rope frequently under normal circumstances, so that the workload is relatively greatly reduced, and the quality of bored pile is not affected. Therefore, this innovation has a high promotion value.

 

Chinese PinYin : Qian Dao Hu Da Qiao