Cofferdam construction plan, what are the construction methods of cofferdam?

Earth-rock cofferdams, wood sheet pile cofferdams, wooden cage cofferdams, steel sheet pile cofferdams, lock pipe column cofferdams, concrete cofferdams, double-walled steel cofferdams, etc.

Definition of cofferdam construction technology: refers to the temporary enclosure structure built for the construction of permanent water conservancy facilities in the construction of water conservancy projects. Its function is to prevent water and soil from entering the construction site of the building, so as to drain the water in the cofferdam, excavate the foundation pit, and build the building. Rotten.

Cofferdam construction technology cofferdam is generally mainly used in hydraulic construction, except as part of a formal building, cofferdam is generally dismantled after use. Pile sinking for bridge construction.

Pile sinking for bridge construction.

Bridge construction pile sinking, which is equivalent to a section of columns hammered into the sea by a pile driver, the material of these columns will vary according to the water flow environment, generally steel, prestressed reinforced concrete and other corrosion-resistant materials.

The same rough Lixiang with the ship to pull the pile to the designated position, and then use the offshore pile driver to drive into the seabed section by section, and so the pile foundation needs to be done to do the cushion cap, the deep-water cushion cap will use the bottom box cofferdam, and the shallow water cushion cap is the steel sheet pile cofferdam water barrier. This was done by installing the upper piers, which were mostly prefabricated in advance and transported by ships.

Summary. Cofferdam construction process: 1

Construction preparation: including mechanical equipment preparation and technical preparation. 2.

Construction sequence: technical disclosure, measurement and lofting, construction of drainage facilities, construction of cofferdam, foundation pit excavation, foundation pit foundation treatment, foundation pit inspection.

Soil cofferdam: first remove the debris at the bottom of the weir, select the soil type according to the actual situation (it is advisable to use cohesive soil or sand clay), fill the weir head along the slope from the exposed water surface, and tamp it in layers after filling out the water surface.

Soil sack cofferdam: use straw sack sack fire geotextile bag to pack most of the bag of soil, sew the bag mouth, and stack it is up and down, left and right.

Sheet pile cofferdam: Sheet pile is suitable for river beds with sand or cohesive soil within a water depth of 3m. During construction, the positioning shape is first laid and the guide frame is installed, the hanging pile is in place, and the pile shoe can be driven after installing the pile shoe on the top of the pile.

Steel sheet pile cofferdam: suitable for pier foundation cofferdam with a water depth of 10-30m. Construction technology:

1.Choose reasonable construction machinery and equipment according to the actual situation. 2.

Inspect sheet piles and other mechanical equipment. 3.Install the cage.

4.Inserting and closing steel sheet piles. 5.

Pumping and plugging leaks. 6.Sheet piles are removed.

The construction process and content of the foundation pit cofferdam.

Cofferdam construction process: 1Preparation for construction:

Including mechanical equipment preparation and technical preparation. 2.Construction Sequence:

Technical disclosure, measurement and lofting, construction of drainage facilities, construction of cofferdam, excavation of foundation pit, treatment of foundation pit, inspection of foundation pit. Soil cofferdam: first remove the debris at the bottom of the weir annihilation, select the soil type according to the actual situation (it is advisable to use cohesive soil or sand clay), fill the weir head along the slope from the exposed water surface, and tamp it in layers after filling out the water surface.

Soil sack cofferdam: use straw sack sack fire geotextile bag to pack most of the bag of soil, sew the bag mouth, and stack it is up and down, left and right. Sheet pile cofferdam:

Wooden sheet piles are suitable for river beds with a water depth of less than 3m, sand inner soil or cohesive soil. During construction, the positioning shape is first laid and the guide frame is installed, the hanging pile is in place, and the pile shoe can be piled after the pile boot is installed on the top of the pile: it is suitable for the foundation cofferdam of the reed bridge pier with a water depth of 10-30m.

Construction technology: 1Choose reasonable construction machinery and equipment according to the actual situation.

2.Inspect sheet piles and other mechanical equipment. 3.

Install the cage. 4.Insert and close the steel sheet piles with the slip.

5.Pumping and plugging leaks. 6.

Sheet piles are removed.

Hope mine can help you.

Have a great day.

According to the layout of the ground bridge, Zhuzhen Bridge, Huajiabin Bridge, Zhuanglishan Bridge and a box culvert (nameless small bridge) are fully synchronized according to the traffic relief plan and the general schedule, and the cofferdam construction is carried out.

Cofferdam refers to the temporary enclosure structure built in the construction of water conservancy projects for the construction of permanent water conservancy facilities.

Its function is to prevent water and soil from entering the construction position of the building, so as to drain the water in the cofferdam, excavate the foundation pit, and build the building.

Generally, it is mainly used in hydraulic construction, except as part of a formal building, and the cofferdam is generally dismantled after use. The height of the cofferdam is higher than the maximum water level that may occur during the construction period.

Cofferdam, with soil pile to build a trapezoidal section of the earthen embankment, the slope of the water surface should not be steeper than 1:2 (vertical and horizontal ratio, the same below), the side slope of the foundation pit should not be steeper, usually filled with sandy clay.

The earth cofferdam is only suitable for shallow water, slow flow rate and impervious soil layer at the bottom of the cofferdam. In order to prevent the slope of the frontal surface from being scoured, it is often used to fill the soil with stones, turf or straw bags. Rockfill cofferdam can also be used in rock-producing areas, but the outer slope is covered with soil layer to prevent seepage and water leakage.

According to the Code for Design of Diversion in the Construction of Water Conservancy Projects (SL623-2013) and the Code for the Organization Design of Water Conservancy Engineering Construction (SL303-2004), the crest elevation of the downstream cofferdam is determined according to the design flood standard during the construction period. The specific calculation method can be found in these two specifications.