Article

Characterisation of Claw–floor Contact Pressures for Standing Cattle and the Dependency on Concrete Roughness

Magnel Laboratory for Concrete Research, Department of Structural Engineering, Ghent University, Technologiepark Zwijnaarde 904, B-9052 Ghent, Belgium; e-mail of corresponding author:
Biosystems Engineering (Impact Factor: 1.36). 01/2003; DOI: 10.1016/S1537-5110(03)00064-3

ABSTRACT Inadequate properties of concrete floors in livestock buildings seem to be an important cause of cattle lesions. High local pressures on claw tissues may contribute to damage of the claw. Monitoring of foot-to-ground pressure distributions may provide insight in the relation between high local pressures and foot lesions.In the current research, the pressure distribution of the foot-to-ground contact area was recorded using thin film tactile sensors. During the experiments, the sensor was located between previously prepared bovine claws and concrete samples with different surface roughness. The measurement procedure permitted a gradual increase in the vertical load on the claws at a test bench, while at the same time the contact area and the pressure distribution could be registered. Five different levels of surface roughness were obtained by finishing fresh concrete samples with a metal float, a wooden float or a brush, and by washing the concrete surface to two different degrees.The results showed a clear increase in contact area with increasing pressure. The abaxial wall and bulb of the claws had the major load-bearing function. The metal-floated concrete resulted in the largest contact area and the lowest pressures, while the washed concrete resulted in much smaller contact areas and higher pressures. Other finishing methods gave intermediate results.The maximum pressure under a load of 4 kN was about twice as high on a wooden-floated or lightly washed surface (around 40 MPa), compared to a metal-floated surface (around 20 MPa). On the severely washed out surface, the maximum pressure was even four to five times higher. This may indicate a higher risk on claw lesions due to local overload.

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