Big Bad Curves?, Pumping Fiber-Reinforced Wet-Mix Shotcrete

Making good pumpable concrete or wet­ mix shotcrete is not always easy, especially
when fibers are present Adding fibers to ordinary wet-mix shotcrete sometimes re­
results in nonpalpable or difficult-to-pump concrete. Simply adding superplasticizer 10 fiber-reinforced shotcrete does not always result in a workable mixture.

Evolution of Fiber Reinforced Shotcrete

The concept of reinforcing shotcrete with discrete, disominous steel fibers was developed by the Battelle Research Corporation in the USA in the early 1970s.

Shotcrete Rehabilitation of a Vancouver, BC Historic

A heritage high-rise building in Vancouver, Canada required rehabilitation due to corro­sion of the steel frame and cracking in the masonry infill. Brick masonry was segmentally removed from the face of this 15-story-high building to expose the steel beam and column framjng system. Steel corrosion products were removed by needle scaling and sandblasting. New steel plate was welded to the beams and columns where required to strengthen the structure to its original design. Rebar was installed in the previously brick-filled cover to the steel frame and a high quality, low permeability silica fume shotcrete was applied to encase the rebar and fill the void. The south side of the building was

Seismic Reinforcing of Masonry Walls With Shotcrete

Photos and newsclips show­ing hundreds of collapsed homes bury­ing entire families have become all too commonplace. As residents of North America we are thankful that this sort of calamity doesn’t happen here. The earth­quakes we’re used to seeing (mainly in California) cause inconvenience and in some cases property damage, injury and even some deaths, but nothing as cata­strophic as in Turkey this year and Azerbaydzhan a few years back.

Shotcrete Expands Gambling in Colorado

The old mining towns of Central City and Black Hawk, Colorado have enjoyed legalized limjted stakes gambling for the past eight years. Not coincidentally, property values are at their highest levels ever. Commercial developers wanting to get in on the action continue to search for possible sites for casinos and resorts. The high price of “traditional” real-estate has led to an unusual solution. The developers have started to cut away at the steep slopes that surround the towns and put casinos and resorts where mountains once stood. But cutting away moun­tains leads to conditions of instability, for which corrective measures must be taken.

Bond Strength of Shotcrete Repair

A good concrete or shotcrete repair must possess three prime char­acteristics: 1) the repair material must be durable in an aggressive environment, 2) the repair must be well bonded to the substrate and 3) the repair must be as crack free as possible to efficiently protect any embedded steel reinforcement from corroding.