Behaviour of piles driven in chalk

Driving resistance is difficult to predict in chalk strata, with both pile free-fall self-weight ‘runs’ and refusals being reported. Axial capacity is also highly uncertain after driving. This paper reviews recent research that has explored these topics. Programmes of onshore tests and novel, high-value offshore, experiments involving static, dynamic and cyclic loading are described. The key findings form the basis of the Chalk ICP-18 approach for estimating the driving resistance and axial capacity of piles driven in low-to medium-density chalk. The new approach is presented and the highly significant impact of set-up after driving is emphasised. It is shown that Chalk ICP-18 overcomes the main limitations of the industry’s current design guidelines by addressing the underlying physical mechanisms. While further tests are required to enlarge the available test database, the new approach is able to provide better predictions for tests available from suitably characterised sites. A new Joint Industry Project is outlined that extends the research to cover further axial, lateral, static and cyclic loading cases

Statewide Implementation of the Surface Performance Graded (SPG) Specification for Chip Seal Binders in Service: Implementation Report

Project 5-6616-01Over the past almost 20 years, a Surface Performance-Graded (SPG) specification for chip seal binders was developed and validated using laboratory measurements and visual field performance of 141 highway sections. This SPG specification was established in an effort to extend the service life of chip seals and save approximately $9 million per year by providing a binder grading system and associated selection guidelines that: (1) accounts for differences in climate and (2) uses existing equipment and performance-based properties that preclude bleeding and aggregate loss in the critical first year of service after construction. This report documents a multi-year implementation effort that includes: (1) further validation and (2) industry interaction including outreach, state round robin testing programs, laboratory characterization efforts with private laboratories, and associated work with a national task force. The SPG specification now available as a special provision to Texas Department of Transportation (TxDOT) Item 300 (SP 300-011) will replace the TxDOT Chip Seal Binder Material Selection Table with the tiered system and conventional chip seal binder specifications for materials in service provided in TxDOT Item 300

Geotechnical Baseline Report Wastewater Line Relocation at Waterloo Park Waller Creek Tunnel Inlet Facility

This report contains design and construction specifications for the Waller Creek Tunnel and shaft, ground conditions, geologic setting, and illustrations for the vicinity map, plan of borings and generalized subsurface profile.Waller Creek Working Grou