Deep foundations for an eternal arch

The holes were dug into the street for the foundations, and concrete poured in a large block. On top of this, a steel form has been put in place to hold the rebars and the poured cement that will form the column holding up the arch.

Looking into the hole, the size of the concrete block is apparent. It sits on bedrock. Notice the four holes in the block.

A boring machine drills through the four holes in the cement block, into the bedrock. The new holes go 28' down through the bedrock. Anchors will be installed to hold the block to the bedrock.

The anchors through the foundation into the bedrock will make the foundation earthquake (tremblor) proof, so the arch should really be eternal.

foundations

The forms for the foundations of the Chinatown Royal Arch are being put in place on Somerset Street, just a few doors east of Cambridge. The current sidewalk will be widened, taking over a bit of one traffic lane on each side of the street.

The foundation hole was dug down to bedrock. The 130+ ton weight of the structure will be carried by foundations down to the bedrock. The visible part of the pillars are have already been made, and are in the yard behind the Yangtze Restaurant.

The same as for most construction projects, the preparation work seems to take forever; the actual assembly of the arch will be quick.

arch foundations

Construction workers have dug the holes for the foundations of the arch. The foundation will come up through what is now the curb side lane of the street. When finished, this area will be a wider sidewalk zone.

While the hole does not appear very deep, it goes down to bedrock, providing a sound foundation for an arch to last forever.