What is a vibro foundation? What is the specific construction method and process of vibro foundation

<>1. Basic overview of foundation vibroflotation method:

Vibroflotation method, also known as vibrating water punching method, is to lift the vibroflot with a crane, start the submersible motor to drive the eccentric block, so that the vibrator produces high-frequency vibration, start the water pump at the same time, spray high-pressure water flow through the nozzle, under the joint action of vibrating and punching, sink the vibrator to a predetermined depth in the soil, after cleaning the hole, fill the gravel from the ground to the hole section by section, so that it is compacted under the action of vibration, and the vibrator can be lifted after reaching the required compactness, and so on until the ground. It is a fast, economical and effective reinforcement method to form a large-diameter dense pile body in the foundation and form a composite foundation with the original foundation to improve the bearing capacity of the foundation and reduce the settlement.

Second, the working principle of foundation vibroflotation method:

The upper part of the vibroflot is a submersible motor, and the lower part is a vibrating body. When the motor rotates, the hollow shaft of the vibrating body is driven to rotate by the elastic and ballasted coupling, and the shaft is equipped with an eccentric block to generate horizontal vibration force. A water injection pipe is installed in the hollow shaft, and the water pressure can reach megapapeb.

The vibroflot is sunk to the desired depth by vibration and water injection from the bottom of the tube, and then vibrates while boosting the punch while filling the gravel until the filler and the surrounding soil are compacted (the vibroflotation process is shown in the figure). In addition to the vibroflot, the vibroflot method still needs walking lifting devices, pumping water transmission systems, control consoles and other equipment.

In the 30s of the 20th century, Germany first used this method to vibrate the sandy soil foundation. In recent years, it has been used in cohesive soils. The method of filling the vibrating hole of saturated clay with crushed stone and forming a stone pillar through vibrating density (also known as the stone pillar method) mainly plays a role in displacement.

The resulting foundation should be calculated as a composite foundation.

Vibro foundation is a commonly used foundation treatment method to improve the mechanical properties and load-bearing capacity of the foundation by applying vibration or shock forces to the foundation. The control of the strength of the vibro foundation mainly depends on the following data:

1.Geological Survey Data:

Geological survey data provide insight into the structure of stratigraphic spikes, soil properties, and groundwater levels. This data can help to determine the appropriate parameters and schemes for vibration or shock forces during the construction of vibro foundations.

2.Soil mechanics parameters:

Soil mechanics parameters are important indicators to evaluate the strength and deformation characteristics of foundations, including soil shear strength, compressive modulus, Poisson's ratio, etc. These parameters are usually obtained through laboratory tests and field tests to provide the basis for the design and control of vibroflotation foundation construction.

3.Vibroflotation test data:

During the construction of vibroflotation foundations, vibroflotation tests are carried out to monitor the response of the foundation to macrofluids and improvements. By monitoring the application of vibroimpulse, vibration frequency, vibration time, and guessing the response of the foundation, it is possible to evaluate the improvement of foundation strength and the construction effect, and then adjust the vibration foil parameters to achieve the expected foundation strength control.

4.Real-time monitoring data:

During the construction of vibroflotation foundations, real-time monitoring can be carried out, including the measurement of surface settlement, vibration velocity, pore water pressure and other parameters. These data can be used to evaluate the deformation and stability of the foundation, and then control the effect of vibroflotation construction and the control of foundation strength.

In summary, the control of foundation strength in vibroflot foundation construction mainly depends on geological survey data, soil mechanical parameters, vibroflotation test data and real-time monitoring data. The analysis and comprehensive application of these data can guide the design and construction of vibro foundation to achieve the desired foundation reinforcement effect.

Summary. Characteristics of vibro foundation Vibro foundation is the use of vibrator water punching holes, filled with sand and gravel aggregate, by the horizontal and vertical vibration of the vibroflot, vibrating the filler, forming a gravel pile and the original foundation to form a composite foundation to improve the bearing capacity of the foundation. It is to lift the vibroflot with a crane, start the submersible motor to drive the eccentric block, so that the vibroflot produces high-frequency vibration, and at the same time start the water pump to spray high-pressure water flow through the nozzle.

Characteristics of vibro foundation Vibro foundation is the use of vibrator water punching holes, filled with sand and gravel aggregate, by the horizontal and vertical vibration of the vibroflot, vibrating the wheel dense filling, forming a gravel pile and the original foundation to form a composite foundation to improve the bearing capacity of the foundation. It is to lift the vibroflot with a crane, start the submersible motor to drive the eccentric block without signal, so that the vibroflot produces high-frequency vibration, and at the same time start the water pump to spray high-pressure water flow through the nozzle.

Under the combined action of vibration and high-pressure water flow, the vibroflot sinks to a predetermined depth in the soil, and then goes through the hole cleaning process, and after the thick mud in the hole is brought out by circulating water, the filler is added to the hole section by section from the ground.

1.The vibroflotation method is suitable for treating sand, silt, silty clay, plain fill and miscellaneous fill. For saturated cohesive soil and saturated loess foundation with undrained shear strength of not less than 20kpa, its practicability should be determined by field test before construction.

Vibroflotation encryption without filler is suitable for treating medium and coarse sand foundations with a clay content of no more than 10%.

2.For large-scale, important and complex site stratigraphy projects, the treatment effect is determined through field tests before formal construction.

Actually, I really want to say that the basis is that the conditions you give are too small and you don't want to. For the sake of me copying so many copies, hope!

1.Project Overview.

The foundation of a plant is buried to a depth of 4m, located on the silt layer, the bearing capacity characteristic value of the natural foundation is 80kpa, the bearing capacity characteristic value required to be achieved after reinforcement is 250kpa, and the allowable settlement is controlled to be 80 140mm. Due to the soft soil of the foundation, it cannot meet the design requirements, and the vibroflotation method is used to reinforce.

Table 7-4 Quality inspection standards for vibroflotation foundations.

2.Engineering geological conditions.

The distribution of soil layers from top to bottom is: fill, average thickness; clayey silt, average thickness; silty soil, average thickness; fine sand, average thickness; The following is a denser silty clay. The water table is generally below the natural surface.

3.Solution:

The vibroflotation method is used to reinforce, the reinforcement depth is 9m, the spacing of the vibropunching holes is triangular arrangement, and two rows of piles are added to the periphery of the foundation. The pile filler per meter is.

The filler is crushed stone, and the maximum particle size is 40mm.

Dump truck filler. The vibroflot is suspended with a rigid guide frame and a pipelayer system. The vibroflot is ZCQ-30 type, and 3 cranes are working at the same time. The construction adopts a parallel propulsion sequence.

4.Reinforcement effect.

The characteristic value of bearing capacity can be increased by more than 5 times to meet the requirements. After 10 years of use, the maximum settlement was measured and did not exceed the allowable value of 140 mm.

5.Techno-economic effects.

At that time, the local filler per cubic meter was converted to about 40 yuan. The total cost is 600,000 yuan less than the original design of reinforced concrete piles, accounting for 30% of the total cost. Save 690t of steel and 200m3 of wood

1950t of cement, the construction period was shortened by nearly 1 year.

Vibro foundation is a kind of deep and dense foundation in foundation treatment technology. The vibroflotation method, also known as the vibrating water punching method, is to lift the vibroflot with a crane, start the submersible motor to drive the eccentric block, and make the vibrator produce high-frequency vibration; At the same time, start the water pump, spray high-pressure water flow through the nozzle, under the joint action of vibrating and punching, sink the vibrator to a predetermined depth in the soil, after clearing the hole, fill the hole from the ground to the hole section by section, so that it is compacted under the action of vibration, and the vibrator can be promoted after reaching the required compactness, so repeated filler and vibrating density, until the ground, a large diameter dense pile body is formed in the foundation and the original foundation constitutes a composite foundation, thereby improving the bearing capacity of the foundation, reducing settlement and uneven settlement.