FTG ENG | eBooks

Positioning mistakes and omissions Mistakes in the location of foundation steps and pilasters, anchor bolts poured incorrectly, and missing steel embeds for structure and stair attachments are all too common in concrete work. If you're using a tape measure to position anchor bolts, for example, it can be particularly hard to achieve precision. If any mistakes happen and aren't caught when the concrete is still wet, you could face costly back charges, rework, and reputational damage. Precast concrete issues When precasting concrete walls and panels, you need to be sure door and window block-outs, embeds, rebar, and picking eyes are placed correctly during setup. If materials have been prefabricated based on inaccurate measurements or calculations, the negative impacts can escalate. You could end up paying for additional crew time and equipment like expensive cranes, not to mention refabrication, to make things right. Ideally, there are few if any errors, and those mistakes that do occur are caught early on, resulting in only a request for information (RFI) and/or a change order. But depending on how serious the error is, it could still take a lot of time and effort to correct. If structural components are already in place, the situation only worsens as every delay erodes the project schedule and budget, as well as your profit margin. In the worst cases, errors aren't identified or properly prioritized during construction, compromising the finished structure and creating a potentially catastrophic safety hazard. Inaccurate Layout: A Shaky Foundation for Structural Work Since as much as 25% of a contractor's costs come from the layout process, getting layout right the first time can set the tone for the entire project. Layout professionals have a big job to do and many responsibilities to account for. They must: ý Anticipate and mitigate errors before and during layout ý Continuously check their work ý Understand how layout will be used by various trades and contractors, especially at the beginning phases when concrete and steel figure in prominently ý Visualize how layout translates to a finished structure ý Communicate and collaborate effectively with construction teams But it's not unusual for problems and mistakes to occur at the layout phase. And when they do, a series of structural errors can follow: ý Building components can't be installed correctly or must be ripped out if errors are discovered later ý When components can't be installed as expected, an RFI or change order is needed, which takes additional time as you wait to receive input from several other people ý On top of that, actually correcting the error or miscalculation takes even more time ý All of that extra time leads to delayed schedules and budget overruns ý Any prefab work that needs to be installed is also impacted Layout work is a critical part of the project, and it's already challenging enough. If your current layout processes aren't as efficient, thorough, or accurate as they could be, you may be unknowingly building upon a shaky foundation and putting yourself at greater risk. Some contractors are selected specifically because they can accurately and efficiently set anchor bolts for heavy machinery and steel columns. 4

• Cover