Free Fall Ball Penetrometer Booster for Seabed Depth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining soil strength parameters in offshore structures, such as cone penetration tests and free fall ball penetrometers, face challenges including high overburden stress, limited penetration depth, and inaccurate data due to complex forces and rotation during penetration, which complicates the interpretation of soil characteristics.
Innovation Solution
A free fall ball penetrometer with a booster is developed, featuring a connecting rod and a cylindrical booster with ellipsoidal tip and rear fins to enhance directional stability and penetration depth, equipped with a load cell and accelerometer for accurate data collection and analysis, allowing for deeper and more stable penetration without additional loading devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a free fall ball penetrometer is used without a booster, then the operation procedure remains simple, but the penetration depth is limited and measurement accuracy decreases
Solution Approach 1:
The penetrometer system is divided into two functional segments: the ball penetrometer for measurement and the booster for depth extension. The booster consists of a cylindrical body with ellipsoidal tip and rear fins, connected to the ball penetrometer via a connecting rod. This segmentation allows the booster to provide additional penetration depth while keeping the measurement components separate and functional.
Solution Approach 2:
A connecting rod serves as an intermediary element between the booster and the ball penetrometer. This intermediate component transmits the penetration force from the booster to the ball penetrometer while maintaining structural integrity and allowing relative movement during the penetration process.
2Measurement precision
If a free fall ball penetrometer is used without directional stability control, then the device structure remains simple, but the ball rotates during penetration affecting measurement accuracy
Solution Approach 1:
The booster is designed with a cylindrical body featuring an ellipsoidal tip and streamlined rear, creating a curved aerodynamic profile that promotes stable vertical orientation during free fall and penetration. This curved geometry naturally aligns the penetrometer vertically, preventing rotation and improving measurement accuracy without complex active control systems.
Solution Approach 2:
The rear fins attached to the booster create an asymmetric structure that provides directional stability during free fall. The fins generate aerodynamic forces that correct any deviations from vertical orientation, ensuring the ball penetrometer maintains a stable vertical position during penetration into the seabed.
3Measurement precision
If conventional penetration methods are used, then the equipment setup is straightforward, but the measured data requires complex calibration and correction steps
Solution Approach 1:
The patent replaces complex mechanical calibration systems with direct electronic measurement using a load cell and accelerometer. These sensors directly measure the penetration resistance and motion parameters, eliminating the need for manual calibration steps and complex correction factors required by conventional methods.
Solution Approach 2:
The penetrometer system performs self-calibration through its embedded sensors that automatically record and transmit measurement data. The load cell and accelerometer provide real-time data on penetration force and motion, allowing the system to self-correct for variations in penetration conditions without external calibration interventions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The free fall ball penetrometer with a booster achieves improved measurement accuracy and deeper penetration into the seabed, enabling more reliable determination of soil undrained shear strength and strain-rate parameters by accounting for end bearing resistance, drag force, and buoyancy, while maintaining simple operation procedures.
Implementation Method 1
a free fall ball penetrometer with a booster... The ball penetrometer is dynamically penetrated into the seabed with the aid of the booster
Implementation Method 2
after free fall in the water column without any loading device
Implementation Method 3
A load cell is added to the present invention, the measured accuracy is further improved based on the data both from the load cell and accelerometer
Implementation Method 4
based on the acceleration data measured during the penetration of the ball within the soil
Implementation Method 5
The booster comprises a cylindrical shaft 3b with ellipsoidal tip and streamlined rear to reduce the resistance of booster during its free fall in water and dynamic penetration in the soil. Four rear fins 3d connected to the booster rear can improve the directional stability of the booster 3 during its free fall process in water
Implementation Method 6
The forces acting on the free fall ball penetrometer is complex. The soil drag force, together with the soil strain-rate effect, should be taken into consideration
Data Source
AI summary
A free fall ball penetrometer with a booster is dynamically penetrated into the seabed through its kinetic and potential energies. The main measuring instrument is a ball penetrometer, which is subject to end bearing resistance, drag force, and soil buoyant force during the dynamic penetration process within the soil. Based on the measured data from the accelerometer and load cell, the soil strength parameters including the undrained shear strength and strain-rate parameter can be back-analyzed. The added booster can: (1) effectively increase the penetration depth of the ball penetrometer and hence enlarge the range of measured penetration depths; and (2) improve the directional stability and avoid the rotation of the ball penetrometer during the falling process. The force data measured from the load cell, together with the acceleration data from the accelerometer, can further improve the measured accuracy.