Are you prepared to start the project and engage the architect and engineers? Do you have all the relevant information they’ll need to hit the ground running? Does your design team know and understand the project goals, objectives and process that will take your napkin sketch and turn it into a reality?
Here are a few items that you should have ready to go before you contract your design team of architects and engineers:
We’ve dealt with a lot of projects that didn’t have an RFP, let alone a clear and concise RFP document to pass along to prospective bidders. We’ll typically get a call and be asked to provide a proposal, but know nothing of the project. Sure, we can gladly provide you a proposal – once we know what to propose on. Having a clear and concise RFP document to forward to bidders will allow you to get an “apples to apples” comparison, rather than a disarray of misinformation.
Does your RFP contain:
- Detailed project description
- Concise project goals and objectives
- Any required engineering and design standards your company has for the project (EGGs, DEPs, REPs, etc)
- Proposed schedules, milestones, and timelines
- Insurance requirements (for the architect and engineers)
- Contract type and description
- Terms and conditions
- Clear instructions to bidders on how to respond to the proposal
- Criteria to be used in the evaluation and selection
- Procedures for RFP questions and answers
This is often overlooked and is critical for the architect and engineers to start their design work. The geotechnical report provides many critical pieces of information and without that information, the design team is at a standstill.
Foundation system recommendations:
The geotechnical engineer should provide a few different foundation system recommendations. From that recommendation, it’s up to the owner to select a foundation to proceed with. There’s a misconception that the architect or structural engineer selects the foundation system – this is incorrect. The design team can assist the owner with developing a pro’s and con’s list and estimate costs associated with each option, but ultimately, it’s the owner decision to select the foundation system.
Ensure the report is recent and accurate for the specific site:
It may be convenient and cost effective to reach for an old soils report and say it “should be good,” but knowing your soil conditions for your specific site is essential to avoid lengthy and costly redesign efforts and project delays. Soil conditions can differ greatly from one lot to the next and without the soils investigation, you’re gambling with assumptions that may or may not work and could cost you more money and time in the long run.
Depending on project and scope, a Geotech report could take 4-8 weeks to finalize. The timeline could be longer if borings/ drillings are required. So it’s best to plan ahead and have this information ready to go when the project kicks off.
For the design team to proceed with the project, we typically request the owner provide the following items (via the Geotech report):
- Boring Logs with USGS elevations for each boring (within 1 ft). Boring depths must encompass entire deep foundation depth recommended for design
- Map of boring locations
- Identification of ground water in borings with USGS elevations
- Seismic Classification in accordance with the governing building code
- Soil creep design information associated with sloping terrain
- Discussion of expansive or settling soils
- Discussion of liquefaction potential
- Discussion of known unusual subsurface conditions (i.e., abandoned mine shafts, etc.)
- Discussion of potential difficulties with building and utility excavations due to soil materials (i.e., sand, bedrock at surface, etc.)
- Sulfate levels in soils (corrosive soils can affect the design criteria for foundations).
- Frost depth
Geotechnical Info & Structural Engineering:
Structural engineers will require the following information before any foundation design can begin:
- Owner selected foundation system (spread footings, drilled piers, post-tensioned slab on ground, mat, etc)
- Estimated movement expected for the recommend foundation types
- Allowable bearing pressures for building and any site retaining walls
- Span spread for foundations due to settling soils
- Minimum footing sizes
- Coefficient of friction for sliding of spread footings – specify if coefficient is service level or ultimate
- Active lateral earth pressure
- Passive lateral earth pressure
- At rest lateral earth pressure. Include pressure distribution for full depth of excavation if structure retains more than one story below grade
- Discussion of probability of ground water encountered during drilled pier construction.
- Horizontal modulus of sub-grade reaction for all strata
- Vertical modulus of sub-grade reaction for all strata
- Minimum dead load requirements for footings and or drilled piers
- Slab-on-grade design and construction, and anticipated slab movement
- Structural slab on ground recommendations if applicable
- Grading and over-excavation recommendations
- State whether 1/3 stress increases are allowed for wind and or seismic loading
- Vapor barrier recommendations
- Vertical and Laterally-loaded pile design information
Similar to geotechnical information, a site survey and grading plan is critical for the architect and engineers to proceed with the design. Granted, most plant locations are reasonably flat, but this critical information is needed to identify what’s below the surface surface – underground utilities, abandon utilities, etc. These items may affect the new design and impact construction activities if they’re discovered too late in the game.
- Shall be tied to plant grid
- Shall show site topography at 1’ max contours
- Show any subsurface utilities, piping, sewers, power lines, gas lines, fiber, duct banks, etc.
- Show overhead utilities at site and along access to the site within the plant
- Show access roads within 100’
- Show adjacent/existing buildings
- Show overall Plant key plan w/ blast contours
When applicable, the blast design criteria is necessary for any design effort. Most facilities already have a facility siting study or blast risk analysis completed, but this information should be current and valid. Similar to the geotechnical report, there’s probably different blast scenarios and criteria identified in the risk analysis, but it’s up to the owner to convey to the design team which criteria is applicable for the project. The architect and engineers don’t interpret the risk analysis, so we require the owners to provide the following information before any design work begins:
- Building Response Level per ASCE . Past publications used different terms like Building Damage Level (BDL), or Building protection level, but the most current ASCE nomenclature is Building Response Level.
- Peak side-on pressure PSO = ____ psi
- Equivalent triangular impulse IW = ___ psi-msec
- Direction of blast wave: ___
Optional but useful Criteria:
- Equivalent impulse duration tD = ___ msec
- Front wall reflected pressure PR = ___ psi
- Front wall effective duration tE = ___ msec
- Roof / side wall peak pressure PA = ___ psi
- Roof / side wall rise time tR = ___ msec
- Roof / side wall total positive duration t0 = ___ msec
- Rear wall peak pressure PA = ___ psi
- Rear wall rise time tR = ___ msec
- Rear wall total positive duration t0 = ___ msec