380 likes | 399 Views
Explore history, construction, and challenges of the Ruidoso Dam seepage project. Learn about site investigations, design options, and progress at the 2015 NMWDOC Spring Workshop.
E N D
Grindstone Seepage Mitigation ProjectVillage of Ruidoso Ed Toms 2105 NMWDOC Spring Workshop May 12, 2015
Overview • History • Site Investigations • Construction Contracting • Design • Closing and Questions 2015 NMWDOC Spring Workshop
History • 139-foot high gravity Roller Compacted Concrete Dam • 1,300-foot long section • Built in 1986 • Water supply to the Village of Ruidoso 2015 NMWDOC Spring Workshop
History - Plan View 2015 NMWDOC Spring Workshop
History - Sections 2015 NMWDOC Spring Workshop
History - Facing Elements 2015 NMWDOC Spring Workshop
History - Issues • High seepage issues since first filling in 1988 • Repairs in 1989, 1996, 2002, and 2009 • Seasonal trends • Winter higher seepage rates • Interviews with Original construction personnel - • Poorly zones of partially cemented aggregates • Transverse thermal cracks 2015 NMWDOC Spring Workshop
History - Issues • High seepage issues since first filling in 1988 • Repairs in 1989, 1996, 2002, and 2009 • Seasonal trends • Winter higher seepage rates • Interviews with Original construction personnel - • Poorly zones of partially cemented aggregates • Transverse thermal cracks 2015 NMWDOC Spring Workshop
Site Investigations • Reservoir at El. 6874. El 6860, where lower seal would be installed, was below water. • Cored 3 vertical rustication joints – Joints 44, 46, & 50. • Excavated a test pit at Joint 49 – confirmed foundation contact likely as indicated on record drawings. • Concrete facing was cracked through at all joint locations cored. • Segregated, poorly consolidated RCC encountered at concrete/RCC interface is a potential seepage pathway behind liner. • Sealant in many of the vertical joints was randomly separated from the sides of the joint. 2015 NMWDOC Spring Workshop
Investigations – Vertical Joints 2015 NMWDOC Spring Workshop
Investigations – Vertical Joints 2015 NMWDOC Spring Workshop
Investigations – Vertical Joints 2015 NMWDOC Spring Workshop
Investigations – Vertical Joints 2015 NMWDOC Spring Workshop
Construction Contracting Method • Design/Bid/Build • Construction Manager at Risk (C-MAR) • Construction Manager/General Construction (CM/GC) • Design/Build • Project schedule defined delivery method – CM/GC • CARPI Liner and Contractor • Worked closely with AECOM during the design • Priced the project based on unit measures • Issued a Guaranteed Maximum Price (GMP) • $3.5 million 2015 NMWDOC Spring Workshop
Partial Lining Option • Advantages • Lower impact on VOR water operations • Less expensive • Disadvantages • Lower probability to improve stability and mitigate seepage • Sealing facing at 6860 against all pathways may be difficult and costly • Remobilization costs if sealing does not mitigate seepage effectively or if stability is in question 2015 NMWDOC Spring Workshop
Complete Lining Option • Advantages • Higher probability to improve stability and mitigate seepage • Double seal and grouted cutoff costs not needed and put towards liner • No remobilization costs • Disadvantages • Higher impact on VOR water operations • More expensive, 27,500 SF more compared to lining to dam bottom above 6860 • Requires additional excavation and dewatering 27-foot dead pool below intake invert 2015 NMWDOC Spring Workshop
Design Elements 2015 NMWDOC Spring Workshop
Design Elements 2015 NMWDOC Spring Workshop
Design Elements 2015 NMWDOC Spring Workshop
Design Elements 2015 NMWDOC Spring Workshop
Design Elements 2015 NMWDOC Spring Workshop
Foundation Excavation 2015 NMWDOC Spring Workshop
Dry Pack Mortar 2015 NMWDOC Spring Workshop
Liner and Internal Profile Material 2015 NMWDOC Spring Workshop
Anchor System 2015 NMWDOC Spring Workshop
Curtain Holes Urethane Grout Injection 2015 NMWDOC Spring Workshop
Construction Coring of Face Element 2015 NMWDOC Spring Workshop
Chemical Grout 2015 NMWDOC Spring Workshop
Vertical Joint Low-Modulus Epoxy 2015 NMWDOC Spring Workshop
Progress – Water Installation 2015 NMWDOC Spring Workshop
Installed Tension Profile 2015 NMWDOC Spring Workshop
Final Installation Example 2015 NMWDOC Spring Workshop
Questions? Ed Toms ed.toms@aecom.com 2015 NMWDOC Spring Workshop