Design methods aci building code the aci building code aci318 does not contain any provisions specifically for deep pile caps. Dec 06, 2019 pile caps can be designed using the truss analogy or using the bending theories. Pile spacing, edge distance, and pile cap thickness. The main components of the foundation are the pile cap and the piles. The first reinforced concrete design manual formerly titled aci design handbook was developed in accordance with the design provisions of 1963 aci 318 building code by aci committee 340, design. Determine maximum pile stress from lpile output associated with the maximum bending moment. Pile cap design software pile cap design software dengebre structural op 12 mar 15 20. Pile foundations are the part of a structure used to carry and transfer the load of the structure to the bearing ground located at some depth below ground surface. Depending upon type of soil, pile material and load transmitting characteristic piles are classified accordingly. Design the pile cap shown in the following figure with 12 in.
Reinforced pile cap design, in accordance with bs8110. Generally, pile cap transfers the load form the structures to a pile group, then the load further transfers to firm soil. Excel spreadsheet pile cap design bs8110 example jobs. Lpile is a specialpurpose and internationally recognized computer program based on rational procedures for analyzing a pile under lateral loading using the py method. Compression steel calculation and shear on 3pile cap corrected. Appendix b columnto pile cap connections appendix c pile to pile cap connections this design guide has been developed to provide the practicing engineer with a detailed overview of pile cap design, detailing, and analysis methodologies that represent the current state of practice in the industry. A fourpile group supports a 500 mm square column which carries a factored load of 2800 kn. Piles are long and slender members which transfer the load to deeper soil or. The course gives a brief background of the types of piling utilize in deep foundations. Instructional materials complementing fema p751, design examples pilepier foundations view of cap with column above and piles below foundation design 29 passive resistance see figure 4. Sep 07, 2011 perimeter at punching shear plane in a pile cap shear stress in concrete in pile cap design concrete shear stress in concrete shear stress in concrete for shear due to bending about xaxis shear stress in concrete for shear due to bending about yaxis modified design shear stress to take into account axial compression design shear stress in.
These piles are often over 15 m long at distances of 1 to 4 m. In this example, the limiting factor for helical pile design is the compression and shear load requirements. H pressure distribution and divide the layer into two equal layers. Foundation design 92 reinforcement of shallow foundation 92 depth of shallow foundation 95 depth for pile cap 98 slab on grade 101 chapter 3. Raft is the same structure to a pile cap and it is a concrete foundation floor supported with soft soil that is accountable for subsidence. Pile under pile cap should be layout symmetrically in both directions. Apr 24, 2015 the structural design of a pile cap is, in principle, not af fected by the type of pile to be used, because it is primarily dependent on the magnitude of the pile reaction. Design examples there are five readytouse example files to familiarize you with this software including examples of tension, compression, tieback, soil screw, and end bearing and friction applications.
The pile cap design procedures in this trm have been prepared in accordance with. Equations derived considering the strut and tie model are available to calculate the area of. Pile foundations more economic to be used when solid bearing stratum i. Final foundation design the last phase completes the geotechnical report and allows the final structural design to begin. The factors that determine the depth of the pile cap include. Pile cap design spreadsheet jobs, employment freelancer. The preliminary geotechnical assumptions are checked and recommendations are modified, if necessary. The column is reinforced with longitudinal bars of 12 no. Pile group carries a vertical load of 5000 kn including the weight of the pile cap.
Check the pile structural adequacy for each row of piles. The purpose of this program is to allow gdot microstation users to create and revise pile bent input files. If possible, these piles are driven into the soil at the positions of walls and columns of a building. A pile cap is defined as a concrete block cast on the head of a group of piles, to transmit the load from the structure to the group of piles. This chapter covers the pile bent application for bridge design. Oct 04, 2014 design of pile cap procedures and examples image the term pile cap may be used to describe a reinforced concrete slab constructed on top of a group of foundation piles to evenly displace or spread the load they are to carry. This program is for microstation v8 and newer data. Figure 1 shows the formation of typical potential plastichinges.
Our programs provide a valuable tool to engineering firms that can be easily incorporated into operations because they are quickly learned. In the following chapter we learn about, classifications, functions and pros and cons of piles. The compression load requires a pile group whose individual pile capacities equal or exceed the 835 ton per column. Settle number of pile placement of pile cap and plane dimension pile cap elementary depth verify forces. The design anchorage length l bd is taken from the basic required anchorage length l b,rqd multiplied by up to five coefficients. The pile cap achieves greater rigidity from the increased depth, which enables it to evenly spread the load to all piles in the group. The piles are 450 mm in diameter and spaced at 50 mm centres. The 2012 edition of the reinforced concrete design manual sp1711 was developed in accordance with the design provisions of aci 31811, and is consistent with the format of sp1709. Pilecap design example using truss analogy design of. Bridge pile bent georgia department of transportation. The program computes deflection, bending moment, shear force and soil response. Appendix b columntopile cap connections appendix c piletopile cap connections this design guide has been developed to provide the practicing engineer with a detailed overview of pile cap design, detailing, and analysis methodologies that represent the current state of practice in the industry. Nothing presented here shall supersede sound engineering design and judgment. Substructure design chapter 7 wsdot bridge design manual m 2350.
Shrinkage and swelling of the ground particularly in clay soils. By using the pile cap design software for structural engineer firms that we created, you can avoid all those problems before the structure is even built. Pile cap design analysis software programs for structural. Twall design examples the following three design examples illustrate the application of the twall design procedure outlined in section 3. Potential inelastic damage has occurred at the interface between pile heads and pile cap as evidenced in recent earthquakes. Thus, designs are based on the procedure for slender footings that can be divided into three separate steps. Generally, pile caps are constructed to connect one pile, two piles, three piles, four piles or a group of files. In general it is designed like a footing on soil but with the difference that instead of uniform reaction from the soil, the reactions in this case are concentrated either point loads or distributed. These examples are provided to help users understand the stepbystep procedure. A pile design example reflecting the procedures in the guideline is included in the appendix.
The design of a foundation shall be consistent with the expectation that structure collapse is prevented and that life safety is protected. It should be noted seismic performance of piletopile cap connections. Design of a pile cap the institution of structural engineers. External pressures on a pile are likely to be greatest near the ground surface. How to calculate anchorage and lap lengths to eurocode 2 introduction. Summary of bill of quantities civil works bar bending schedule. The national annex documents to be published separately from the eurocodes. Pile cap design software structural engineering general. Aug 18, 2015 design of pile cap as per is 2911 part i sec 3 2010, the pile cap may be designed by assuming that the load from column is dispersed at 45 from the top of the cap up to the mid depth of the pile cap from the base of the column or pedestal. The axial loads on the column are due to dead and live loads and.
The load of the building is transmitted by the cast concrete pile cap into the piles. Design example of pile cap for concentric loading civil. The column or wall on pile cap should be centered at the geometric center of the pile cap in order to transferred load evenly to each pile. After exporting spcolumn input files, the pile and column designinvestigation can. Throughout this guideline, the term lrfd, when followed by a section or table number, is used as a reference to. Solution stress distribution begins at the bottom of the pile group in stiff clay media. I am looking for a good pilecap design program and was wondering if anyone had any recommendations. Pile caps can be designed using the truss analogy or using the bending theories. The trial pile length for the calculation is 63 feet below the bottom of pile cap excavation which extends 3 feet below grade.
Pile cap design calculation civil engineering community. Mostly, up to the four numbers of piles are connected by a pile cap to support the concentrated load from the superstructure, truss theory is used to design the pile caps. Dimensions of the pile caps are decided based on the loads and connecting arrangement of the superstructure and the pile foundation. Download to your hard drive simply by clicking on each one. Matlab file, matlab function, truss analysis, plane truss, visualization, view all files of finite elements method. Sachpazis date 100820 chkd by date appd by date rc pile cap design bs8110.
The ultimate pile capacity70 kip pile and service load capacity42 kip pile as conformed by testing. The pile cap has normalweight concrete with a compressive strength of 4000 psi and grade 60 reinforcement. In general, piles should be spacing at 3 times of pile diameter in order to transfer load effectively to. Examples to aci, aisc and asce interactive calculation templates to us codes u. Pile design and construction practice, fifth edition. Grade of concrete m 30 grade of steel fe 500 size of column 680 x 300 mm axial force 1560 kn moment mx 339 knm moment mz 0. Once calculation the bending moment the pile cap depth can be. Pile supported foundation pile cap analysis and design.
A pile cap have to support a 18x18 column which is subjected to live load170 kips and dead load160 kips under service loading. Piles are long and slender members which transfer the. Foreword the reinforced concrete design manual sp1711 is intended to provide guidance and assistance to professionals engaged in the design of castinplace reinforced concrete structures. Flexible pavement design, calculator, sn, aashto design, structural number. This course covers the design of pile supported foundations.
Steel design 102 wshapes in strong axis bending, braced at some points 102. Pile cap design spreadsheets to eurocode 2 en 19921. Thermal cracking of concrete pile caps editora dunas placement in layers of small height, precooling and postcooling of concrete comptia network n10 005 pdf download filetype pdf. It should be noted seismic performance of pile to pile cap connections.
This course is a good introductory course for engineers new to the design and analysis of pile cap design and is a good refresher for experienced engineers. The design moment and reaction for monolithic support should generally be taken as the greater of the elastic and redistributed values critical design moment usually at face of support. An example project is used for program data throughout the document. Instructional materials complementing fema p751, design examples pile pier foundations view of cap with column above and piles below foundation design 29 passive resistance see figure 4. The purpose of this design example is to demonstrate that when more strict construction control is applied, fewer uncertainties are involved, since the pile resistance can be field. In general, piles should be spacing at 3 times of pile diameter in order to transfer. Lrfd rectangular bent cap design example the texas. The pile cap should normally be rigid so as to distribute the forces equally on the piles of a group. Download pile cap designing excel excelsheet for pile cap. Use the estimated group deflection under the lateral load per pile to determine the maximum bending moment for an individual pile in each row. For a foundation, such as a pile cap or pad base, this can affect the depth of concrete that has to be provided.
How to calculate anchorage and lap lengths to eurocode 2. The lateral load requirement necessitates enlarging the shaft of the. The strutandtie model approach evolves as one of the most useful design methods for shear critical structures and for other disturbed regionsin concrete structures the model provides a rational approachby representing a complex structural member with an appropriate simplified truss models there is no single, unique stm for most design. I would prefer a program that uses a fem solution to determine the pile cap forces, pile reactions, design the reinforcement, etc. Design guide for pile caps crsi resource materials. Compare maximum pile stress with pile yield stress.
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