by Platipus Inc | Nov 17, 2022
MSD Shiva Court – Wildwood, St. Louis, MO
Project Overview
Construction of a block retaining wall was required for protection of stream bank during storm events. While soils were determined to be competent and able to stand at near vertical cuts, the risk of toe cutting and subsequent instability and mass wasting during increased flow from storm events forced MSD to require temporary shoring to eliminate those risks.
Options for shoring included, but was limited to: sheet pile, soldier pile with sheeting, braced sheeting, soil nailing, and tiered multi-plane shoring. Sheet piling, soldier piles or any sort of bracing required removal after the wall had been constructed.
Solution
Upon temporary wall evaluation and weighing options, Platipus S6 ARGS assembly (1-ton rated) was selected to be installed on a 4’ horizontal by 4’ vertical spaced grid pattern. Anchors were installed perpendicular to slope face, driven to 12’ depth, and tensioned to the design working load of 1,100 lbs. using a Platipus SJ3 hydraulic load jack. The excavation and shoring was directed by the designing engineer to be constructed from the top down, in 4’ vertical lifts. The facing on the cut included a nonwoven filter fabric, a geogrid layer, a W4.0 x W4.0 Welded Wire Fabric, with point loading spread using 4” x 4” x 24” long timber restraints. The terminating end of the wire steel tendon included a 5” diameter 14 gauge stainless steel load plate and stainless steel conical wedge grip.
The contractor enjoyed significant cost savings over conventional shoring options.
by Platipus Inc | Nov 17, 2022
Bridgewater WWTP – Bridgewater, NJ
Project Overview
A proposed pump station for the SRVSA Stormwater Treatment Facility located in Bridgewater, NJ would require footers and foundations to be constructed 45’ below grade. Borings revealed the soil profile consisted of 8’ of fill/alluvial material and 8.5’ residual clay overlaying shale bedrock. Engineers also had to consider live loads (1,594 psf) associated with a nearby crane. For the soil reinforced elevations, the engineer determined that a tensile capacity of at least 6,000 lbs./ft (of wall/slope) was required to satisfy a factor of safety of 1.3 for temporary support.
Solution
The engineer determined that Platipus S8 ARGS (2 Ton Capacity) anchors placed on a 5’ horizontal by 3’ vertical grid pattern would safely support the required excavation, at least to the elevation where bedrock was expected to be encountered. As with any shoring of excavation application, top-down construction was required. Beginning with the initial 4’ cut, the first row of anchors were installed 23’ deep using a mini-excavator with an attached light weight breaker/hammer. Each S8 anchor was tensioned to the design working load of 2,000 lbs using a Platipus SK1 hydraulic jack and electric pump prior to excavation of subsequent lifts. Once bedrock was encountered, the contractor transitioned to an appropriate rock bolt/anchor (provided by Williams Form Engineering) that was specified by the engineer. Platipus engineering assistance and onsite support throughout the project made the S8 ARGS system the preferred method of shoring of excavation (of soils) for the contractor.
by Platipus Inc | Nov 17, 2022
I-278 Bridge Rehabilitation – Staten Island, NY
Project Overview
This design-build project included shoring of walls under existing I-278 bridges so that new structures (traffic lanes and new MSE walls) could be added. The engineer determined that B4 and B6 anchors on a 5’ horizontal by 3’ vertical grid pattern would be needed to stabilize and temporarily support existing traffic lanes while the new MSE structures were to be constructed in front of the supported cuts. It was determined that the anchors were to be driven to 9’ in one section and 13’ in another section, while each anchor would be pulled to the design (working) load of 4.0 KIPS (4,000 lbs.).
Solution
This portion of the project was fast tracked, Platipus design assistance began in November of 2018 with approvals and ordering of readily available B4 and B6 anchor assemblies in December with construction and installation taking place in the 2 subsequent months. The GC was pleased with Platipus design, pre-construction and onsite assistance, construction of the temporary structures was completed the following month.
