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ACTT Workshop: Montana
January 26-28, 2004, Missoula, Montana
Chapter 3 (continued): Workshop Meeting Details
3.2 Workshop Process and Recommendations
3.2.5 Geotechnical and Materials
To facilitate accelerated construction of this project, the Geotechnical and Materials skill set divided recommendations into three broad categories: accelerated construction - materials and methods; accelerated acceptance - tests and inspection; and pit sites.
Methods and Materials
- Use for ground improvement for embankment foundation. It will make the ground harder and eliminate settlement.
- Can utilize quick installation method.
- It can also be utilized to provide foundations for shallow footings in lieu of piles.
In discussing jet grouting, the Geotechnical and Materials group noted that it is quick, but expensive, if wicks don't work. However, in using jet grouting for shallow foundations (such as bridge structures) there is a cost savings in time (get in and get out) that counterbalances the additional upfront expense. On some grades there may also be an issue of dynamic compaction or densification when using jet grouting. Alternatives may be geofoam or rubber chips. Each has their detractors. Jet grouting may be a hard sell to the MDT Bridge Division while geofoam is expensive and rubber chips are heavy and flammable.
Welded Wire Walls/Precast Concrete Panels for Wall Facings
- Welded Wire Walls offer several benefits for this project. They can be built in less time and any type of architectural facing can be added at any time (i.e., they go in as a two-phase wall with facing being completed after settlement). Precast panels or other facing aesthetic can be utilized with a generic spec that is easily bid. It was noted that there is corrosion potential with some backfills, but this was not thought to be an issue with the soils being used on US 93.
Alternatives to Bridge/Animal Crossings Construction
- Bridges and Animal Crossings can be constructed at night only or over a few accelerated construction days to minimize traffic disruptions. Pipe jacking and top down construction methods can facilitate this accelerated construction.
- Bridge spans could be shortened to reduce embankment/wall height/footprint requirements. For example, on the Jocko River Bridge the adjacent beam heights could be reduced with a resulting savings on approach costs (in line with Washington standard). The main span could be kept as designed but the approach grade could be lowered 0.6 m (2 ft, pushing 1:1 slope) with the possibility of going to a five span in lieu of current three span.
- Eliminate piles at wildlife overpass by utilizing MSE walls and spread footings. This may face some resistance at MDT as they haven't built a lot of spread footing bridges in Montana. There is the institutional impression that every spread footing bridge has sunk.
Controlled Staging of Geotech Work
- Schedules and sequencing requirements should be specified up front.
- Methods should be utilized to facilitate work under/in traffic. This could be accomplished by routing two lanes at a time with initial work on the opposite side of the roadway or by temporarily shifting lanes to the shoulder/ditch area.
- Cut slopes to avoid excessive excavations and ROW takes (use slightly steeper cut slopes or small toe cuts).
- Bi-axial geogrids can be used to reduce the thickness of special borrow and pavement sections. Bi-axial geogrids are currently being used in other places with research showing good results.
- Utilize geofoam in areas where lightweight fill is needed/acceptable.
- Soft-cement stabilization should also be examined as a viable method for this project.
Tests and Inspection
- Subgrade special borrow will be pre-approved A-1-a. It saves time because it is R-value tested during preconstruction (meaning testing does not have be completed during construction).
- Utilize maturity testing for concrete curing and/or measurement of strength gain (set a thermo coupler or embedded chip). This provides onsite determination when to strip forms and complete backfill, resulting in time savings.
- It is recommended that a corridor-wide team approach be utilized for this project with MDT and consultant staff working together (MDT is concerned with staffing and wants to avoid new FTE). Such a team should provide several measures of consistency resulting in efficiencies of time. The design consultant as well as a CSKT liaison could be invited to preconstruction, prebid, etc. meetings. Going back to the design consultant if errors or problems emerge would also be beneficial.
- One option is to have state (MDT) coordinated QA only. This option should be exercised only if MDT mandates contractor/consultant provided QC.
- This project should encourage proactive identification of problems allowing them to be addressed early in the process.
- It is recommended that MDT coordinate centerline staking and engineering checks with the option to include earthwork staking. All surveying should be tied to GPS.
- Involving design consultants proactively is critical, particularly in preconstruction and "status" meetings.
- Have pre-approved mandatory borrow sites. There are plenty of sources/sites that are ready to be utilized (approximately 20 identified). Royalty values should be addressed prior to bid. The pit plan can be coordinated with borrow method spec. However, the possibility of specifying no mixing of sources/blends needs to be determined.
- Incorporate stakeholder criteria in pre-approved reclamation processes and plans to insure reclamation of sources. It should be noted that CSKT pits are already under mandate to not conflict with surrounding areas (eleven of the identified borrow sites are on CSKT lands).
- Have prepared criteria to assess proposed contractor pits. Such pits offer a potential project savings and should be evaluated in conformity with stakeholder criteria. Furthermore, preapproved processes and reclamation details will save time.
3.2.6 Innovative Contracting
The Innovative Contracting skill set organized their discussion into four areas or techniques that can be utilized in exploring state-of-the art contracting practices: delivery methods, procurement methods, contracting methods, and other tools.
- Use design-build for the SEIS portion. Utilizing design-build for the SEIS section of this project may result in faster project delivery and enhanced environmental streamlining as well as allowing for best-value procurement. However, this contracting method is limited by legislation and the multiple entities, stakeholders and resource agencies involved in this project may make approval particularly difficult.
- Examine job order contracting for such items as erosion control, stream restoration, etc. (defined further in final recommendations).
- A+B (defined further in final recommendations).
- Best Value A+B+Q (cost plus time plus qualifications). Contract awarding is based on price and non-price factors as well as qualification evaluations. It identifies up front specific areas of concern (key personnel, past performance, safety plans, quality management plans, etc.). This procurement method also has legislative hurdles - Montana state law currently requires low bid.
- Lane Rental (defined further in final recommendations).
- Incentive/Disincentive provisions include bonuses or deductions for certain contract milestones or features. They can be particularly beneficial in areas of cultural sensitivity or where there exists a desire to minimize environmental impacts (i.e., clearing and grubbing areas). Barriers to implementation include the need to adequately educate the contractor to reach contract goals; valuing impacts; and measuring the quality of work and relating it to incentives/disincentives.
- Warranties are the guarantee of the integrity of a product and of the maker's responsibility for the repair or the replacement of deficiencies. They offer the possibility for longer-life elements, and ultimate end product or performance related specification. They also hold the contractor accountable and initially decrease the number of MDT project personnel (shift responsibility from MDT to contractor). However, the number of personnel needed after contract completion increases (to ensure long-term contractor compliance). The administration and definition of warranties can also become barriers to warranty implementation. New contract provisions will be required and the possibility exists that bid costs will increase as contractors look at possible future deductions.
- Escalation Agreements help define the decision making process. They reduce the time needed to make decisions, change orders, resolve conflicts and modify schedules. They offer quicker problem resolution and facilitate clear communication lines.
- Drop Dead Dates (no excuses completion dates).
- No Excuse Bonuses (incentives only, L/Ds still apply).
- Performance Related Specifications defines the measurement for acceptance of a completed item (i.e., the end result). This offers significant opportunity in bridgework and work zone control. It allows for greater contractor innovation and more efficient use of resource allocation. However, some contractor education may be needed, and MDT would have to rethink their method specs. For this project, the design process has already proceeded too far.
- Value Engineering (VE) Clauses (based on time).
- Contractor Constructability Reviews (defined further in final recommendations).
- Construction Manager. This individual would be a consultant contracted to provide administration of all projects in the corridor (one manager to manage the entire corridor).
- Consultant Quality Assurance.
Following interaction with the other skill sets; Innovative Contracting identified four final recommendations to accelerate construction of this project. These final recommendations, as well as a synopsis of the associated benefits and implementation issues, are listed below.
Recommendation: Use job order contracting for selective pieces of work that do not have definable quantities (similar to term contracts). Pieces of work to consider include erosion control measures, landscaping, seeding, environmental features, etc.
- Promotes just-in-time procurement of these elements.
- Allows the prime contractor to focus on areas of expertise.
- Can more easily cancel contract for non-performance.
- This is a new delivery method.
- Coordination with prime contractor is critical (coordination requirements should be defined up front).
Recommendation: Consider using A+B (cost plus time) bidding method on all projects. Assign a monetary value to contract time.
- Decreased construction time resulting in reduced impact and increased safety to the traveling public.
- Encourages contractor innovation.
- Decreases contract administration costs.
- Must re-evaluate the definition of "B" portion. Have multiple "B" milestones to compensate for short construction season/winter shutdown.
- Evaluate the use of seasonal road user costs (RUCs).
Recommendation: Use lane rental (incentives/disincentives for lane usage and width restrictions) when two-lane, two-way traffic is not practical.
- Minimize congestion.
- Minimize lane closures.
- Incentive can be tied to time of day and high volume seasons.
- Promote innovation in sequencing.
- New contracting method. There is a lack of experience in Montana when calculating rates.
- Relationship to A+B specification needs to be defined.
- May increase contract administration costs.
Recommendation: Use contractor constructability reviews on all sub-projects. Contractor constructability reviews are a process that involves experienced construction personnel with extensive construction knowledge early in the design stages of a project to ensure that the project is buildable while also being cost effective, bidable and maintainable.
- Introduces construction knowledge into design (i.e., takes a proactive approach to problems).
- Encourages exchange of ideas on new contracting methods, environmental issues, borrow sites and features unique to this project.
- Promotes reasonable schedules for "B" portion of contract.
- Allows refinement of traffic control plans and sequencing prior to initiation.
- Coordination with contractors.
- Legal issues. Contractors involved in reviews may have an advantage over other bidders.
Nearly all phases and aspects of roadway construction have an impact on the environment in some way. Hence, any discussion of environmental recommendations can be put in context of its impact on other skill sets. Construction, traffic/work zone safety, geotechnical and materials, innovative contracting and structures were all identified as having topics or areas that would need to be coordinated with the Environmental skill set. These interim topics follow:
- Sequence of operations - specifically, bull trout and stream restoration.
- Fall lettings were identified for bull trout and stream restoration, as well as removal of the old Jocko River structure (this will need a special provision).
- Dust control plans for (predetermined) haul roads should be initiated.
- Detours and alignment shifts that might have an impact on sensitive areas need to be addressed.
Traffic/Work Zone Safety
- Identify alternate routes and have a contingency plan in place for issues such as air quality, maintenance coordination, etc.
Geotechnical and Materials
- Institute a surcharge for settlement areas.
- Use job order contracting (2 year increment contracts) for erosion control, seeding, and landscaping
- While utilization of A+B+Q contracting, where Q would include quality environmental stewardship, is ideal, it cannot be done under current legislation. However, an incentive for environmental stewardship could be worked into an A+B contract (i.e., A+B plus best value bidding or A+B plus prequalification through specifications).
- Encourage innovation! Use three people (construction, environmental, and innovative contract specialists) to develop special provisions, or review existing drafts, for incentives on environmental stewardship, level of quality for wetland and stream restoration as well as landscaping features. Emphasis should be placed on incentives versus disincentives and could include mitigation sites and additional miscellaneous work.
- Consider changing from constructability reviews to PS&E.
- Short list or prequalify contractors for stream restoration, wetlands, and landscaping tasks. (Takes state legislation to prequalify contractors.)
- Structure heights, beam depths, wildlife crossing, temporary facilities, etc. should be designed and permitted prior to bid letting. Some construction activities adjacent to structures will likely be necessary.
- Let one or more structures as separate contracts from roadway contracts.
As discussions continued, several additional interim recommendations came to light. One particular need was for onsite resource decision makers or an environmental coordination and compliance team. These resource representative(s) would have authority to make decisions for changes that may come up during construction. While the concern exists that they may not have full authority to make changes to mitigation plans or permits (Tribal, 404, NPDES, etc.) the possibility of having "ranges" of flexibly for changes exists. Regardless, having a resource representative on site would improve implementation of mitigation commitments.
A log of existing conditions should also be developed. A basic photo log or other recording method for cultural and other important tribal sites would be adequate.
The Environmental skill set organized its final recommendations into six basic areas: general construction concerns; traffic/work zone safety; right-of-way/utilities/railroad; public relations/ITS; innovative contracting; and structures. These areas, and the subsequent recommendations for accelerated construction, follow:
General Construction Concerns
- Staging Areas (wetland mitigation sites) should be preapproved. A team approach can be utilized to identify upland or other areas that can be used. It would be preferable to use hard surfaces to reduce mud tracking. Old borrow sites can be used for contractor borrow, staging or plant operations. These same old sites can then be reclaimed and used for restoration credit.
- Separate contracts should be issued for stream restoration, wetlands and landscaping (wetland, urban and rural revegetation/landscaping).
- A specification and pay item for cleaning equipment to address Whirling Disease must be developed.
- Project Oversight Team - determine a project oversight team and resolution process. This team will be charged with working out specifications for rewards and resolving conflicts through a fast-track resolution process. They would hold weekly coordination meetings gathering feedback from the contractor, MDT and CSKT. It is recommended that the team contain the following individuals:
- Environmental Project Manager (EPM)
- CSKT EPM
- Wetland and Stream Restoration Specialist
- Traffic Control Specialist
- CSKT Cultural and Resource Representative (MOA - May need funding assistance of tribal staff)
- Revegetation Specialist (MDT funded)
- Any resolution process that is developed needs to be agreed upon by all three governments (MDT, FHWA, CSKT).
Traffic/Work Zone Safety
- Barriers to wildlife. Long lengths of traffic barriers are not desirable. Currently, we are unsure how many lengths of concrete barrier or silt fence will be used.
- Utility relocations will conflict with some "Do Not Disturb" areas. A resolution to this conflict must still be coordinated. One option is to have MDT fence "Do Not Disturb" areas.
- The Environmental skill set endorses the use of a US-93 Corridor Management Team. The team could include: utility reps, MDT utilities, CSKT and an Environmental representative.
- What is time critical now? The vegetative agreement has been approved and vegetation must be harvested now so that it may be utilized this year (2004).
- Public Relations needs to be proactive in answering the question "Why the project is the way it is?" i.e., what will the public be seeing in the upcoming days, weeks, or months and why will they be seeing it. Focus should be on the positive aspects of the project, highlighting the importance and benefits of critter crossings, mitigating wetlands, limiting access, reducing delays and accelerating construction.
- Qualified contractors must be identified to handle environmentally sensitive projects such as stream restoration, wetlands mitigation (on site and adjacent), and revegetation/landscaping (seeding and erosion control). It is recommended that these contracts be let separately or as job orders. Special provisions for prequalification of contractors should be written, and environmental quality stewardship incentives need to be instituted.
- The formation of a Preconstruction Development Team could proactively identify and write Environmental/Innovative and Construction special provisions.
- Permit temporary facilities prior to bid letting. As the project permitting process is still taking place, there is time to do this.
- When working in wetland areas, pile-driving precautions should be taken to prevent (seal) potential draining of prairie potholes.
Initial brainstorming by the Structures skill set resulted in 49 separate ideas for accelerating construction within the project corridor (see Appendix C for a complete list). As discussions progressed, these 49 ideas were narrowed down to 10 basic areas or topics. These topics included questions (that would need to be posed to other skill sets, MDT personnel, etc.), findings, and initial recommendations.
- Let multiple bridges in one contract, e.g., let Jocko River Bridge, MRL Railroad Bridge and the Evaro Hill Wildlife Overpass in one contract.
- Jack and bore wildlife crossings and culverts.
- Prefabricate as many components as possible including decks, caps, and aesthetic treatments.
- Standardized details should be used where possible.
- Schedule letting so that construction occurs in the winter to avoid traffic and allow the contractor a long lead-time to get prefabrication done.
- Modify specifications to encourage innovative ideas from the contract. Consider tying road user costs (RUC) to value engineering (VE).
- Design/build the SEIS section.
- Concrete specification recommendations.
- Wildlife overpasses should be redone.
- The 6-m (20 ft) deep drilled shaft rock sockets need to be reviewed.
Following continued consideration and intermingling with other skill sets, the Structures skill set organized its final recommendations into five areas: materials, contracts/specifications, construction, design, and bridge recommendations. These areas, and the subsequent recommendations for accelerated construction, follow:
- Use self-consolidating concrete as well as high early strength concrete.
- Use Maturity meter for concrete monitoring.
- Allow fast curing on CIP members, e.g., steam or heat curing for decks.
- Utilize high performance concrete (HPC) on bridge decks. This may necessitate contractor training.
- Allow longer concrete haul times and develop an end result concrete specification.
- Require contractor QC/QA.
- Provide lead-time in the contract schedule to allow contractor to prefabricate as many of the structural components as possible. Consequently, all structural components that can be prefabricated off-site should be, to allow for shorter construction time at the actual project site including caps, decks, and aesthetic treatments.
- Let multiple bridges in one bridge contract so that structures can be constructed as efficiently as possible, e.g., let Jocko River Bridge, MRL Railroad Bridge and the Evaro Hill Wildlife Overpass in one contract.
- Encourage innovative ideas from contractor(s).
- Consider tying RUC to VE specification.
- Consider completing the SEIS portion of this corridor as a design/build project.
- Jack and bore culverts and wildlife crossings into place so that disturbance to the traveling public is minimized.
- Winter or off-season construction of structures should be allowed or required to avoid disturbances to seasonal traffic.
- Utilize constructability review.
- Prefabricate bridge components.
- Where possible, structures should use standardized components such as drilled shaft diameters resulting in a quicker (and smoother) construction time.
Specific Bridge Recommendations
- Jock River Bridge
- Review foundation design and scour analysis (shafts) as 7-m (23-ft) rock sockets appear excessive.
- Utilize the full shaft diameter to the bottom of the cap.
- Eliminate the phase construction of the structure and instead phase-construct the approaches - possibly with reinforced temporary slopes to minimize traffic disturbance.
- Use a full-depth prefabricated deck on prefabricated caps.
- MRL Railroad Bridge
- Review wing wall design (walls for this structure should be squared up with a drilled shaft under them).
- Ensure full shaft diameter to the bottom of the cap.
- Consider providing the contractor the option of using a full depth, precast deck.
- Evaro Hill Wildlife Overpass
- This structure should be redesigned to be more like the other structures in the corridor and let in the combined bridge contract.
- MSE abutments and end walls as well as and prestressed beams should be utilized.
- Spread footing on MSE walls and single span beam should also be considered.
- If the structure will not be redesigned, the existing foundation design should be reexamined, particularly pile footing.
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