Vibration Characteristics of Concrete Pump Trucks with Multiple Postures and Multiple Conditions Based on the Secondary Development of HyperWorks

Abstract

Due to the excitation generated by the periodically alternate pumping of dual-hydraulic cylinders, vibration of concrete pump trucks (CPT) occurs. Excessive boom vibration will seriously affect the service life and operation safety of CPT. At the same time, the long boom structure of a CPT makes it very sensitive to the posture and pumping conditions, which directly affect the vibration characteristics of CPT in different postures and different working conditions. This paper establishes a finite element model of a type of CPT. Through force analysis of concrete in the straight pipe and elbow pipe during the pumping and reversing stages, an excitation model of the conveying pipe is established. Based on the secondary development of HyperWorks, a finite element model of CPT with multiple postures is built, and the dynamic response under multiple conditions is analyzed. Finally, the accuracy of the finite element model of CPT and the excitation model of the conveying pipe is verified by experiment.

About effect of dynamic loading caused by concrete pump on bending moments, anchor forces and deformations in single level anchored retaining wall

“…Truck-mounted concrete pumps represent a special type of concrete pumps (a combination between concrete pump and standard truck chassis), which are very often used during construction process of ordinary residential buildings, industrial facilities and infrastructure projects (bridges, roadways, etc.). Most of the scientific researches in the area are focused only on the dynamic loadings, which are transferred from the pulsating concrete mixture in the flexible tube to the folding boom for concrete laying, as for example: [2], [3] and [4].…”

“…On the basis of obtained vibration frequency and deformations in the folding boom of concrete pump model JJ315/45-K in [4], is possible to be calculated the approximate value of acceleration in the center of gravity of the folding boom Sa [m/s^2] (it is assumed, that center of gravity of boom is located near to the middle length of boom), by using the equation: It is a fact, that all above mentioned scientific researches are focused only on the dynamic loadings, which are transferred from the pulsating concrete mixture in the flexible tube to the folding boom for concrete laying, as well as monitoring and control (active control and passive control) of the dynamic vibrational behavior of folding boom. Nowhere is analyzed the case, when the concrete pump support structure is located near to fortification wall of construction excavation, by which the vibrational loadings from concrete pump ground supports (outriggers) are transferred to the fortification wall of construction excavation.…”

“…, and as a result of that are calculated the approximate values for accelerations and deformations in the vibrating boom of the concrete pump, which are shown in table 1 below: Approximate values for maximal vertical deformations (axis Z) in the top of folding boom of concrete pump model JJ315/45-K[4] and calculated maximal vibration accelerations in the center of gravity of boom, in case of pumped concrete pressure 10MPa and rotational speed of driving internal-combustion diesel engine about 1500rev/min.…”