{"id":1613,"date":"2012-05-31T17:00:24","date_gmt":"2012-05-31T17:00:24","guid":{"rendered":"http:\/\/theflatironblog.com\/?p=345"},"modified":"2016-07-14T23:03:21","modified_gmt":"2016-07-14T23:03:21","slug":"e-e-cruz-uses-top-down-construction-on-columbia-university-campus-expansion","status":"publish","type":"post","link":"https:\/\/www.flatironcorp.com\/news\/e-e-cruz-uses-top-down-construction-on-columbia-university-campus-expansion\/","title":{"rendered":"E.E. Cruz Uses Top-Down Construction on Columbia University Campus Expansion"},"content":{"rendered":"

Since January 2011, E.E. Cruz<\/a> has been\u00a0building foundations for the Jerome L. Greene Science Center<\/a>,\u00a0the first part of Columbia University<\/a>\u2019s ambitious Manhattanville\u00a0project<\/a>, a new 17-acre campus expansion in the West Harlem\u00a0neighborhood of New York City.<\/p>\n

E.E. Cruz will build more than 150,000 square feet of watertight\u00a0perimeter diaphragm wall, or slurry wall, install 96 load bearing\u00a0elements, and excavate and construct the foundations and\u00a0sub-basement. The site covers two city blocks and is one of the\u00a0biggest digs in New York. Project manager Mark Alexander says\u00a0this actually makes the work easier.<\/p>\n\"photo<\/a>\n

\u201cMy crew came from the World Trade Center site, so this is a lot\u00a0of space for us. There we had 100 different contractors working\u00a0in the same small area. We joke that we don\u2019t know how to work\u00a0with all this extra space.\u201d<\/p>\n

The $121 million project is a joint venture between managing\u00a0partner and Flatiron subsidiary E.E. Cruz and Nicholson\u00a0Construction Company<\/a>.<\/p>\n

\u201cWe\u2019ve been working together for 12 years. We\u2019re like brothers,\u201d\u00a0says Nicholson project superintendent Del RasMjou of his joint\u00a0venture partner and counterpart Mark. \u201cIt\u2019s a perfect partnership.\u201d<\/p>\n

As of late May, nearly half of the 96 load-bearing elements had\u00a0been installed. Rigs are on-site drilling six-to seven-foot diameter\u00a0shafts up to 240 feet into the ground below. Once a shaft is\u00a0complete, a rebar cage is installed and filled with concrete. Steel\u00a0beams, each weighing up to 35 tons, are mounted into column\u00a0plungers and elevator beams, then carefully positioned over the\u00a0shafts with large cranes. Accuracy is vital, because the beams\u00a0must be positioned within three-eighths of an inch in every\u00a0direction.<\/p>\n

\u201cThe plunger and elevator beam are so critical because they allow\u00a0us to line up the core beam exactly, so when you set the beam in
\nthe concrete, it\u2019s perfect,\u201d says Mark.<\/p>\n

It takes approximately a day to drill each shaft, and if everything\u00a0goes according to plan, concrete is placed and the beam is set\u00a0the following day. But it can take longer if the team encounters\u00a0something unexpected in the drilling path.<\/p>\n

\u201c\u00a0We’ve\u00a0had tough drilling conditions and stability issues with the\u00a0holes, and we have encountered boulders and nested cobblers\u00a0that have slowed the drilling process,\u201d adds Mark.<\/p>\n

\"photo<\/a>One unique aspect of this project is the\u00a0top-down construction\u00a0sequence. Once the foundation is poured, work will begin on the\u00a0six-story high-rise superstructure while E.E. Cruz simultaneously\u00a0excavates 100,000 cubic yards of soil 60 feet below grade and\u00a0constructs two sub-basement floors.<\/p>\n

\u201cAs we dig down, the slab will be poured and we will continue to\u00a0mine underneath it,\u201d says Pat Roach, general superintendent on\u00a0the project and a 14-year veteran of E.E. Cruz.<\/p>\n

Owner Columbia University went with top-down construction\u00a0because of access constraints.\u00a0\u201cIn conventional excavation you\u2019d use braces or tie backs for the\u00a0walls. But you\u2019d need 300-foot tiebacks in some places, which\u00a0we can\u2019t do here due to property line constraints,\u201d says Mark. \u00a0\u201cPlus, they\u2019ll build vertically while we excavate below, so it\u2019s also a\u00a0schedule saver.\u201d<\/p>\n

Construction in New York City presents a host of challenges for\u00a0E.E. Cruz. The site is next to an active, above-ground subway line,
\nwhich complicated crane operations.<\/p>\n

\u201cWe have to work parallel to the panels because the crane cannot\u00a0be in a position to potentially damage the adjacent rail line,\u201d\u00a0advises Pat Roach.\u00a0\u201cCranes are highly scrutinized, especially when you\u2019re working with\u00a0a long boom crane on a site like this,\u201d says Mark.<\/p>\n

Below ground, there are more hidden challenges for the team.\u00a0Manhattanville was once a \u00a0bustling industrial and manufacturing\u00a0area, and more recently was occupied by warehouses and gas\u00a0stations. Before slurry walls are constructed, teams excavate 18\u00a0feet from the surface to remove debris left over from previous\u00a0structures, as well as contaminated soil from a previous gas\u00a0station.<\/p>\n

\u201cThere are old buildings, basement floors, basement walls\u2014we\u00a0take out tons of stuff,\u201d says Del.\u00a0The new development, of which this is just one building, will take\u00a025 years to complete and add 6.8 million square feet of new\u00a0space for teaching, academic research, parking, facilities support\u00a0and commercial space.<\/p>\n

In mid-March, the E.E. Cruz and Nicholson joint venture team was\u00a0awarded a $44 million contract for phase two of the project, which\u00a0involves constructing another 206,000 square feet of diaphragm wall.<\/p>\n","protected":false},"excerpt":{"rendered":"

Since January 2011, E.E. Cruz has been\u00a0building foundations for the Jerome L. Greene Science Center,\u00a0the first part of Columbia University\u2019s ambitious Manhattanville\u00a0project, a new 17-acre campus expansion…<\/p>\n","protected":false},"author":3,"featured_media":360,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"ngg_post_thumbnail":0,"footnotes":""},"categories":[40],"tags":[127,150,181,183,264,277,282,419,472],"class_list":["post-1613","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-project-news","tag-columbia-university","tag-e-e-cruz","tag-flatiron-construction","tag-flatiron-corporation","tag-manhattanville-project","tag-new-york-city","tag-nicholson-construction-company","tag-top-down-construction-sequence","tag-underground"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/posts\/1613"}],"collection":[{"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/comments?post=1613"}],"version-history":[{"count":0,"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/posts\/1613\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/media\/360"}],"wp:attachment":[{"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/media?parent=1613"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/categories?post=1613"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.flatironcorp.com\/wp-json\/wp\/v2\/tags?post=1613"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}