Screw Conveyor Used to Pour Concrete for Bridge in New Orleans
General Description
Complete Engineering and Construction (CEC) is an Engineering and Construction Contractor headquartered in Lafayette, Louisiana. CEC provides and performs a variety of highway construction services, specializing in new construction, rehabilitation, design-build projects and engineering support.
CEC was awarded the contract to repair a section of the Luling Bridge, outside of New Orleans, LA within a very tight time schedule. CEC needed a solution to slowly move wet concrete from the mixer trucks to the road surface. CEC has an ongoing relationship utilizing Motion Industries for their power transmission and material handling requirements. Motion Industries turned to KWS for the engineered screw conveyor solution.
KWS designed a screw conveyor that would slowly feed wet concrete in a controlled manner. The screw conveyor needed to ship on-time and operate flawlessly due to the critical bridge repair schedule.
Design Parameters
- Product Type: Wet Concrete
- Material Density: 150 Lbs. per Cubic Foot
- Conveyor Capacity: 135,000 Lbs. per Hour
- Moisture Content: 30%
- Duty: 24 Hours per Day, 7 Days per Week
KWS Advantages
Engineers from KWS worked directly with CEC Consulting Engineer, Malcolm Huval, P.E. on multiple calls to design the most robust and feasible solution. KWS reviewed the application requirements and performed design calculations. A ribbon type screw conveyor was selected due to the material characteristics of wet concrete. KWS designed and built a portable integral leg ribbon screw conveyor to distribute the wet concrete across the road surface evenly within a very small envelope and limited height. Engineers from CEC and KWS worked together to generate numerous iterations before settling on a final design. The use of Autodesk Inventor 3D made the process very simple. Special discharge slots were cut in the bottom of the screw conveyor troughs to evenly distribute the wet concrete.
Special Features
The KWS screw conveyor was mounted in a structural frame that was part of the concrete pouring, leveling and finishing system. The structural frame had to support the fully loaded screw conveyor and not interfere with the freshly poured concrete. KWS utilized structural C-channel with cross bracing as part of the screw conveyor trough to increase rigidity. Abrasion resistant (AR) material was used for the screw flights due to the abrasive nature of the concrete. The conveyor inlet was fed by concrete mixer trucks and discharged through a series of rectangular slots cut into the bottom of the trough with multiple irregular width patterns for even material distribution.
The screw conveyor was designed to be modular in order to accommodate two different lane widths. The maximum lane width was 20-feet. The screw conveyor could pour and level the full 20-foot width of the lane. Once poured, the screw conveyor could be modified by removing one screw and trough section to pour a 14-foot lane. Due to the lack of electricity on-site, the screw conveyor was powered hydraulically. KWS utilized a Dodge Hydroil motor and TAII shaft-mounted gear reducer.
Testimonial
"KWS did a great job! The project was completed ahead of schedule and KWS was a great help all the way through the process. I give you guys a 95 out of 100! Thanks!!"
Malcolm Huval, P.E., Project Manager – Complete Engineering and Construction (CEC)
"KWS shipped on-time to meet the Customer’s expectations. Everything went really well! I love selling KWS screw conveyors!!"
Adam Killgore, Outside Sales – Motion Industries