Construction procedures and lrfd design methods, 2010. The mix design, means and method of concrete placement are. Drilled shaft concrete mix design contractor must submit a concrete design mix along with materials, including water reducer, to central materials lab at least 40 days prior to construction, for approval. Sep 16, 2016 placing temporary drilled shaft casing on sr52majestic. Shaft is a computer program used to evaluate the axial capacity and the shortterm, loadsettlement curves of drilled shafts or bored piles in various types of soils. An investigation of load and resistance factor design of. Criteria for the design of axially loaded drilled shafts.
Drilled shaft design software geotechvols geotechnical op 9 jan 10. However, geotechnical design models for axial and lateral. Design and construction of drilled piers, american concrete institute 336. The example is only for the design of the shaft foundation. As part of a fhwa test program for evaluating drilled shafts for bridge foundations. Drilled shaft foundation design spreadsheet currently selected. The cantilever supports a sign panel attached to the horizontal support.
All of the information, data and computer software. Dimaggio of the strategic highway research program shrp2 at the. There are several good reasons to use permanent casing for drilled shafts. Placing temporary drilled shaft casing on sr52majestic. Optionally, the user may enter nonlinear momentcurvature relationships to be used in place of the internallygenerated values. It is imperative that all stakeholders in the process have a good understanding of the basic requirements and characteristics of drilled shaft concrete. Drilled shaft foundations shaft end bearing shaft skin friction constructability downdrag on shaft quality of rock socket. The rock socket should have a diameter 6 inches less than the shaft diameter and may be. Practices for design of bored piles drilled shafts. Im specifically looking for something that includes the structural design of them, not just the py analysis of it, we currently use lpile by ensoft for that. Smallerdiameter piers have been used in noncollapsing soils. Because of torque requirement the diameter and length of cfa piles are generally less than drilled. Sep 16, 2016 placement of temporary drilled shaft placement via vibratory hammer for traffic signal base.
This type of casing is often used when a drilled shaft must be installed through the water and the protruding portion of the permanent casing is used as a form. The drilled shaft methodology is based upon federal highway administration reports. As a general rule, if temporary casing size is not specified, most contractors will use a casing with an o. In general, the majority of axial capacity methods used by shaft are based on the latest fhwa manual. Bridge and pier design philosophy is such that the structure is detailed to force the ductile fusehinge to develop in the pile whereas for buildings, the hinge occurs in the beam. It is important to keep slurries and drilling fluids out of the rock socket.
Jun 29, 2016 it is imperative that all stakeholders in the process have a good understanding of the basic requirements and characteristics of drilled shaft concrete. Design and construction of drilled piers reported by aci committee 336 aci 336. This chapter describes the placement of concrete for drilled shafts, and the design and testing of concrete mixes with emphasis on the unique requirements of drilled shaft concrete. The side shear is related to the shear strength of the soil and in sands can be thought of as the lesser of the friction f r. With the first commercial release release dating back to 1986, lpile has continuously been developed and improved to meet user needs and incorporate stateoftheart literature and procedures. Drilled shaft with both permanent and temporary casing. The demo version is actually the full program but will not allow users to save or run new data models. Kam ng jessica garder sri sritharan jeramy ashlock. The required depth of the concrete pier is calculated by the sum of the movement active zone depth and the pier anchor zone depth see figure 21. Cfa foundation auger cast piles use of casing or slurry to temporarily support the hole is avoided. Service limit state design of drilled shaft foundations includes the evaluation of settlement due. May 15, 2018 this type of casing is often used when a drilled shaft must be installed through the water and the protruding portion of the permanent casing is used as a form. Any drilled shaft for a major river or lake bridge or any drilled shaft longer than 80 ft. Drilled shafts 4 mullins design capacity of drilled shafts the capacity of drilled shafts is developed from a combination of side shear and end bearing.
Drilled shafts caissons or drilled piers are typically high axial and lateral load deep foundation systems. Drilled shafts are either considered to be wet or dry. Cased drilled shafts are required when ground conditions are so unstable that drilled holes cannot safely be stabilized with drilling slurry or where loss of ground must be controlled. Drilled shaft bridge foundation design parameters and procedures for bearing in sgc soils 6. This manual is the reference text used for the national highway institute nhi course numbered 2014 on drilled shafts. Accordingly, this report addresses the applicability of drilled shaft foundations in the railroad industry along with general cost factors, and describes modern. Drilled piers socketed in hard rock are designed based on side resistance only or tip resistance only. Drilled shaft foundations should be designed at the service limit state to meet the tolerable movements for the structure.
Construction practices and defects in drilled shafts. Permanent casing thickness design and plan reporting. If temporary casing has been used to seal a dry shaft excavation, there is often an accumulation of fluid on the outside of the casing. Drilled shafts design and construction slide 34 of 51 1. Design requirements drilled shaft design is performed by obs using the soils design sections s4 package. Where a drilled shaft for a pier is widened at the bottom of the boring. When designing a drilled shaft using temporary casing, contractors. Does anybody have any good recommendations for relatively cheap design software for drilled shafts. I have never seen this done but wanted to see if this is also typical. It includes different analysis methods for sand, clay, silt, and limestone.
The intent of this paper, therefore, is to provide a brief survey of modern drilled shaft technology along with practical guidelines for drilled shaft design and construction inspection. Maintenance of traffic mot odot selective coordination spreadsheet. Subsurface exploration is a necessity for the analysis and design of a drilled shaft landslide stabilization solution. Based on these industry codes, standards, and specifications, reinforcement required for structural reasons in a drilled shaft, whether placed against a casing or with exposed soil, should be positioned using side form spacers.
Currently, kdot allows the use of slurries or drilling compounds above the rock socket only. The contract plans contain the actual shaft design and any and all requirements not covered in the. As the design depends on the construction method, it becomes part of the design process. A cylindrical shaft is excavated, reinforcing steel is placed in the excavation and concrete is placed to form the shaft. Drilled shaft bridge foundation design parameters and. Drilled shaft with both permanent and temporary casing drilled shaft with both permanent and temporary casing. Shaft 123 is a macrodriven excel spreadsheet which utilizes vba programming for calculating ungrouted and grouted drilled shaft capacities. In the most common design condition, a drilled shaft is designed to carry load by side friction in a rock socket. The design methods for drilled shafts presented in this chapter are largely based on empirical. Permanent casing is also used in situations where concrete must be placed in a deep, largediameter, highcapacity drilled shaft in sound rock. The drilled hole for the shaft is kept open with slurry, temporary casing or permanent casing. Strength limit states for drilled shafts lateral geotechnical resistance of soil and rock stratum, for single shafts and shaft groups geotechnical axial resistance compression and uplift, for single shafts and shaft groups structural resistance of shafts, including checks for axial, lateral, and flexural resistances. Recommendations for installation of instrumentation, in the form of inclinometer casing and monitoring wells, are also provided.
Download geotechnical engineering software shaft 2017 developed by ensoft. Placement of temporary drilled shaft placement via vibratory hammer for traffic signal base. Specific task training program drilled shaft foundation construction. Drilled pier bored pile software soilstructure software.
This allows for the passage of a drilling tool of the proper diameter during final excavation of the borehole. Construction procedures and lrfd design methods fhwanhi10016. The manuals authors are three of the countrys top experts in drilled shaft design and construction. The minimum clearance between reinforcing bars shall be 17. The casing can help advance the hole, and supports the sides of the hole. Lpile provides several design recommendations for rebar arrangements in drilled shafts.
Do not define the top of the drilled shaft in the normal manner a set distance below finished grade. Drilling and workover software, drilling software free downloads, completions, preventative maintenance. Example 10 demonstrates a design procedure for a drilled shaft foundation for a cantilever sign structure. In effect, each drilled shaft is a unique construction project, complicaleli by the fact that the drilling and concreting occur mostly out of sight of the drilledshaft contractor and the inspector. Design and construction of drilled piers section 4.
Fb deep is a static axial capacity program used for drilled shafts and driven piles. Temporary casing to the full length of the shaft excavation may be used when the risk of excavation collapse is significant. Up until now, you needed one program for axial capacity, another for lateral load analysis and yet a third program for reinforcement design. Drilling and workover software, drilling software free downloads, completions,preventative maintenance. Performing organization name and address arizona state university 10. Example 10 sign structure foundation design example statement. Cdex, pegasus vertexs casing design software, implements an industryaccepted physics model to perform accurate and practical casing designs for complicated drilling circumstances. Lpile solves the differential equation for a beamcolumn using a finite difference approach.
Drilled shafts installed in lakes or rivers require use of a casing placed from above the water surface to a minimum embedment into the river or lake bottom. Chapter 9 placement and design of concrete for drilled. Drilling the hole in one continuous process is faster than drilling a shaft excavation. Shaft study of drilled shafts under axial loading software. Design a concrete mixture proportioned according to the american concrete institute. Following is a description of a procedure for designing the depth of a drilled concrete pier when the input data from section 1. The use and construction of drilled shaft foundations. N that develops between the shaft concrete and the surrounding soil or the. Drilled shafts design and construction slide 3 of 51 concrete mix design considerations massdot lrfd design manual 2009 section 3. When constructing drilled shafts, casing and liners are vital to the overall. Reinforcement in drilled shaft deep foundations pieresearch. For large and deep drilled shaft excavations, full length temporary casing is most effectively installed using hydraulic oscillator or rotator equipment, in advance of the excavation figure 2. Design capacity of drilled shafts the capacity of drilled shafts is developed from a combination of side shear and end bearing.
There are also some public seats available occasionally at dot hosted. Lpile analysis of piles and drilled shafts under lateral. One of the most important reasons to use casing to keep the hole open is so the bottom can be inspected and thoroughly cleaned. Jul 07, 2010 some nhi courses, including the drilled shaft course, can be hosted by nongovernment groups. The user may define up to 10 pile sections with nonlinear bending properties. The concrete was guided at the top of the excavation and allowed to fall freely without striking the sides of the excavation. The use and construction of drilled shaft foundations prepared by. Drilled shaft design has progressed to the point where shafts can be founded in rocks, shales, clays, sands and gravel, and. The design of the concrete called for a strength of 5,000 psi at 28 days.
Drilled shaft foundations are also referred to caissons, drilled piers, or bored piles, and consist of circular shafts of varying diameter, drilled to a design depth, reinforced with a steel rebar cage, and filled with concrete. The materials are used by the lab to verify the contractors proposed mix design. Drilled shaft temporary casing installation youtube. When permanent casing is or maybe required, this will be the elevation that the casing may not extend below. Casing can be temporary or permanent steel pipe which provides a 100% stable excavation for the full length of the drilled shaft. Given the necessity of a solid foundation for a drilled shaft, concrete. Placement and design of concrete in drilled shaft construction. Load transfer and capacity of drilled shafts with fulldepth casing rolf katzenbach, professor of civil engineering, institute and laboratory of geotechnics. Burst, collapse, tension, compression, bending, buckling and temperature effects are all incorporated into cdex to analyze the casing strings capabilities. This allows a designer to see the effects from say cutting off part of the reinforcing steel at the lower sections of a drilled shaft. Side resistance will not be calculated for material above. Distributed with this memorandum is the publication entitled drilled shafts. Fpasc160 design procedure for drilled concrete piers in expansive soil 17 nov 2017 issued for fpa website publishing foundation performance association structural committee page 1 of 61.
After the concrete had set for approximately two weeks, the drilled shaft was cored, and cores examined visually. The designer shall consider the intended method of construction temporary or permanent casing, slurry drilling, etc. Drilled shaft design software foundation engineering. Software by bridge software institute fbdeep is a static axial capacity program used for drilled shafts and driven piles. This manual embraces both construction and design of drilled shafts, and. Shaft design and detailing recommendations pile detailing. In spite of the fact that the dss performance depends to. A drilled shaft is a deep foundation that is constructed by placing fluid concrete in a drilled hole, typically. Lpile is a specialpurpose and internationally recognized computer program based on rational procedures for analyzing a pile under lateral loading using the py method. There are also some public seats available occasionally at dot hosted courses. But the geotechnical engineer of record is saying that the more prudent option would be to advance the permanent casing down to the bottom of the drilled shaft and then extract it back to elev. Drilling software download free trial downloads try before you buy. When a drilled shaft is constructed with a permanent casing, the skin friction along the.