Delivery Systems - Spring 2010 / by Watershed Materials

The challenge for spring 2010 is all about delivery systems.  We abandoned shovels for conveyors several years ago, but somehow every job seems to warrant a different configuration of belts, trolleys, and rails.

In March we were in Glendale, California.  The owner and general contractor gave us a monumental challenge:  800 linear feet of stratified earth wall to be completed in eighteen days.  The wall was to be comprised of 19 individual strata, four different colors, each lift a different thickness and a different color.  We had to design and build two new delivery conveyors to fit the staging areas we were assigned; one an elevating conveyor that would lift material from the mix rig to a height of 15’ and the other a pivoting/tracking conveyor that would travel along the top of the forms and distribute material for the varying lift depths.  The first photo in this post shows the set up.  As is always the case with prototype equipment, there were hitches at the start.  The first few days were really long ones in order to meet our required quota.  We redesigned and rebuilt the elevating conveyor, adding a powered head pulley, and we modified both the track and the trolley.  The first week it took us nine hours to meet the daily production schedule.  By the second week we were down to seven hours; the third week we were down to six, and the final four days we were placing eight yards an hour, finishing before lunch.
In May we mobilized to a single family residential project in the Los Altos hills above San Francisco Bay.  Here we had to fill a curving form, 120 feet long, two feet thick and in some cases twenty feet deep.  Each of the three set-ups required a different conveyor configuration.  One photo in the post shows our gas powered three-way conveyor.  The other photo shows how we chained four conveyors together to get across the basement excavation and into the 12-foot tall forms.