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From page 58... ... NCHRP Project 12-102 58 C H A P T E R 5 ABC Design Specification Development 5.1 Approach This project is essentially a large-scale synthesis of past work. No formal laboratory research was completed under this project. Read the entire page →
From page 59... ... NCHRP Project 12-102 59 c. Implementation: A high factor of 30 was applied to this measure. Read the entire page →
From page 60... ... NCHRP Project 12-102 60 5.2 Specification Section and Article Development The team was charged with developing guide specifications in AASHTO format. This is not a standalone design specification, but a supplement to the AASHTO LRFD Bridge Design Specifications. Read the entire page →
From page 61... ... NCHRP Project 12-102 61 5.3.2 Article 1.4 - Design Responsibilities for Prefabricated Elements A review of project histories across the country had revealed some confusion regarding design responsibilities for projects with prefabricated elements. The confusion arises from other industries. Read the entire page →
From page 62... ... NCHRP Project 12-102 62 No research was discovered regarding loads in element during fabrication, shipping and erection. The Precast/Prestressed Concrete Institute Design Handbook MNL-120 (2010) Read the entire page →
From page 63... ... NCHRP Project 12-102 63 addressed by the proposed specifications contain connections, and provisions for their design. Those provisions are based on laboratory testing and computational modeling. Read the entire page →
From page 64... ... NCHRP Project 12-102 64 An example of this was used on the 93Fast14 Project in Massachusetts. The closure pours were specified to have 4000 psi concrete based on typical concrete used in bridge decks in Massachusetts. Read the entire page →
From page 65... ... NCHRP Project 12-102 65 Figure 5.5.3.2-1 Technology Readiness Evaluation for Article 3.6.2.1 Read the entire page →
From page 66... ... NCHRP Project 12-102 66 5.5.3.3 Article 3.6.2.2 Hooked Reinforcing Bars The current AASHTO LRFD Bridge Design Specifications for Hooked bars do not specifically mention lap splices of hooked bars. The tension lap splice specification refers to tension development length ld, but not hook development ldh. Read the entire page →
From page 67... ... NCHRP Project 12-102 67 hooked bar is a combination of concrete bond on the bar combined with crushing of the concrete under the hook. The transverse bars serve two purposes. Read the entire page →
From page 68... ... NCHRP Project 12-102 68 Figure 5.5.3.3-1 Technology Readiness Evaluation for Article 3.6.2.2 Read the entire page →
From page 69... ... NCHRP Project 12-102 69 5.5.3.4 Article 3.6.2.3 Headed and Mechanically Anchored Deformed Reinforcing Bars NCHRP Project 10-71 (French, et al, 2011) studied the use of headed reinforcing bars in closure joints. Read the entire page →
From page 70... ... NCHRP Project 12-102 70 Source of data: (French, et al, 2011) Read the entire page →
From page 71... ... NCHRP Project 12-102 71 The concrete strengths used for these comparisons are the approximate concrete strengths used in the research. The concrete strength for NCHRP 10-71 (French, et al, 2011) Read the entire page →
From page 72... ... NCHRP Project 12-102 72 Figure 5.5.3.4-2 Technology Readiness Evaluation for Article 3.6.2.3 Read the entire page →
From page 73... ... NCHRP Project 12-102 73 5.5.3.5 Article 3.6.2.4 Reinforced UHPC Connections There have been a significant number of recent research projects that investigated the use of reinforced UHPC for connections of prefabricated elements. In the opinion of the project team, the FHWA Tech Note entitled Design and Construction of Field-Cast UHPC Connections (Graybeal, 2010) Read the entire page →
From page 74... ... NCHRP Project 12-102 74 conditions were tested as well as different transverse bar arrangements. Fatigue testing was also completed. Read the entire page →
From page 75... ... NCHRP Project 12-102 75 Figure 5.5.3.5-1 Technology Readiness Evaluation for Article 3.6.2.4 Read the entire page →
From page 76... ... NCHRP Project 12-102 76 5.5.3.6 Article 3.6.4.1 General In this section, connections between elements are made by connecting tension bars with mechanical reinforcing bar connectors. Those connectors allow tension to be transferred from one bar to another. Read the entire page →
From page 77... ... NCHRP Project 12-102 77 Figure 5.5.3.6-1 Technology Readiness Evaluation for Article 3.6.4.1 Read the entire page →
From page 78... ... NCHRP Project 12-102 78 5.5.3.7 Article 3.6.4.2 Type 1 Mechanical Connectors The definition of Type 1 connector presented in this article corresponds to a "full mechanical connection" as included in AASHTO LRFD. In the proposed guide specifications, Type 1 mechanical connectors are not allowed in plastic hinge regions for all SDCs or seismic zones. Read the entire page →
From page 79... ... NCHRP Project 12-102 79 Figure 5.5.3.7-1 Technology Readiness Evaluation for Article 3.6.4.2 Read the entire page →
From page 80... ... NCHRP Project 12-102 80 5.5.3.8 Article 3.6.4.3 Type 2 Mechanical Connectors The proposed Article 3.6.4.3 is a compromise between the ACI and AASHTO approaches, because it allows the use of mechanical splices at and near column-footing or column-pier cap interface but, for high seismic zones, it makes provision for the reduced displacement ductility capacity that has been observed in the laboratory with the use of mechanical connectors in plastic hinge zones. For the AASHTO LRFD force-base design in high seismic risk, the reduced ductility is handled in Article 3.6.4.4.1 through the specification of a reduced modification factor. Read the entire page →
From page 81... ... NCHRP Project 12-102 81 Figure 5.5.3.8-1 Technology Readiness Evaluation for Article 3.6.4.3 Read the entire page →
From page 82... ... NCHRP Project 12-102 82 5.5.3.9 Article 3.6.4.4 Type 2 Mechanical Connectors in Plastic Hinge Regions for SDCs C and D (Seismic Zones 3 and 4) There are many types of mechanical connectors commercially available, however, column-to-footing assemblies tested in the laboratory under cyclic loading mostly used headed rebar coupler (HC) Read the entire page →
From page 83... ... NCHRP Project 12-102 83 Figure 5.5.3.9-1 Technology Readiness Evaluation for Article 3.6.4.4 Read the entire page →
From page 84... ... NCHRP Project 12-102 84 5.5.3.10 Article 3.6.4.4.1 Forced-Based Design of Column Connections with Mechanical Connectors for Seismic Zones 3 and 4 Although mechanical connectors can be efficient for developing the ultimate tensile strength of spliced reinforcement, precast connections with these devices have been found to exhibit reduced ductility and energy dissipation capacity as compared to CIP connections with the same reinforcement and no mechanical connectors. This occurs because mechanical connectors are very stiff and thus compromise the column curvature capacity in the splice zone in addition to leading to rebar strain concentrations adjacent to the end of the coupler. Read the entire page →
From page 85... ... NCHRP Project 12-102 85 Δ௬ = ቀ୼೐ோ ቁΩ (5.5.3.10-2) where: Δ௠= peak displacement demand of the nonlinear system Δ௬= yielding displacement of the nonlinear system Δ௘= displacement demand of the linear elastic system R = response modification factor Ω =overstrength factor (= 1.3 in AASHTO LRFD Bridge Design Specifications (2014) Read the entire page →
From page 86... ... NCHRP Project 12-102 86 measured displacement ductility has been measured to be 88% of that for CIP (Haber et al. Read the entire page →
From page 87... ... NCHRP Project 12-102 87 The following is a technology readiness form for this article: Figure 5.5.3.10-2 Technology Readiness Evaluation for Article 3.6.4.4.1 Read the entire page →
From page 88... ... NCHRP Project 12-102 88 5.5.3.11 Article 3.6.4.4.2 Displacement-Based Design of Column Connections with Mechanical Connectors for SDCs C and D Provisions in this section are primarily based on the work by Tazarv and Saiidi (2014, 2015, and 2016) , in which it is recognized that the seismic performance of columns with mechanical connectors in the plastic hinge region is inferior to that of conventional CIP. Read the entire page →
From page 89... ... NCHRP Project 12-102 89 Source: Saiidi and Tazarav, 2016 Figure 5.5.3.11-1 Stress-strain Model for Mechanical Bar Splices Tazarav and Saiidi (2015) verified and calibrated this mechanically spliced column fiber model using available experimental results of column-footing assemblies. Read the entire page →
From page 90... ... NCHRP Project 12-102 90 where: ܮ௣௦௣= ܮ௣ = Figure 5.5.3.11-2 Actual and Idealized Curvature Diagram for Column with Mechanical Connector in Plastic Hinge Region. Figure 5.5.3.11-3 shows the reduced plastic hinge length factor (ܮ௣௦௣/ܮ௣) Read the entire page →
From page 91... ... NCHRP Project 12-102 91 Top: HC, Bottom: GC. Figure 5.5.3.11-3 Reduced Plastic Hinge Length to Account for Mechanical Splice in Plastic Hinge Region: 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 0.0 0.2 0.4 0.6 0.8 1.0 1.2 L ps p /L p Hsp/Lp HC (Lsp/Lp=0.15) Read the entire page →
From page 92... ... NCHRP Project 12-102 92 Table 5.5.3.11-2 shows comparisons of the measured displacement ductility capacity for three columnto-footing assemblies tested in the laboratory with the displacement ductility capacity calculated by Tazarav and Saiidi (2016) Read the entire page →
From page 93... ... NCHRP Project 12-102 93 Figure 5.5.3.11-4 Technology Readiness Evaluation for Article 3.6.4.4.2 Read the entire page →
From page 94... ... NCHRP Project 12-102 94 5.5.3.12 Article 3.6.4.5 Debonding of Column Longitudinal Reinforcement for Mechanical Couplers in the Plastic Hinge Region The provisions in this article are intended to provide an improvement in the seismic behavior when bar connectors are placed at the interface of a precast column with a capacity-protected element. Debonding of column reinforcement into pier cap or footing has been associated with delay of rebar fracture and reduced spalling of adjacent capacity-protected elements (Belleri and Riva, 2012, Mashal et al., 2014, Pang et al., 2008) Read the entire page →
From page 95... ... NCHRP Project 12-102 95 Limiting the tensile strain in the steel to ߝ௠௔௫ = 0.04 for a drift ratio of three percent (φ= 0.03 rad) , the debonding length is calculated to be: ܮௗ௘௕ = ଴.଴ଷ(ௗି௖) Read the entire page →
From page 96... ... NCHRP Project 12-102 96 Figure 5.5.3.12-2 Technology Readiness Evaluation for Article 3.6.4.5 Read the entire page →
From page 97... ... NCHRP Project 12-102 97 5.5.3.13 Column Connections with Mechanical Connectors Not Included in the Proposed ABC Guide Specifications Because of Low Technology Readiness Score This section presents examples of connections that were evaluated in this project but that were not included in the proposed guide specifications because of the low technology readiness score. Over the last decade, experimental and numerical research has been conducted at the University of Nevada Reno with the purpose of developing column connections with mechanical couplers that could reasonably emulate the behavior of reference cast-in-place assemblies. Read the entire page →
From page 98... ... NCHRP Project 12-102 98 Source: Haber et al. 2013 Figure 5.5.3.13-2 Comparison of HC Emulative Column-Footing Assembly Relative to Reference CIP Column Connection with Grouted Sleeve Coupler with Debonded Pedestal (GCDP) Read the entire page →
From page 99... ... NCHRP Project 12-102 99 Source: Tazarv and Saiidi 2014 Figure 5.5.3.13-4 Comparison of GCP Emulative Column-Footing Assembly Relative to Reference CIP Haber et al (2013) developed an analytical plastic hinge model, which was calibrated with test results, and conducted a parametric study to determine the effect of splice length and splice location on the seismic response of column-footing assemblies. Read the entire page →
From page 100... ... NCHRP Project 12-102 100 Figure 5.5.3.13-5 Technology Readiness Evaluation for Column Connections with Mechanical Connectors Read the entire page →
From page 101... ... NCHRP Project 12-102 101 5.5.3.14 Article 3.6.5 Grouted Duct Connections A grouted duct connection shares some characteristics with a grouted sleeve mechanical coupler but differs in its intended function. In both cases a bar is secured by grout into a surrounding metal sleeve. Read the entire page →
From page 102... ... NCHRP Project 12-102 102 Figure 5.5.3.14-2 Technology Readiness Evaluation for Article 3.6.5 Read the entire page →
From page 103... ... NCHRP Project 12-102 103 5.5.3.15 Article 3.6.5.1 Minimum Development Length of Reinforcing Steel Results from pullout tests have demonstrated that corrugated steel ducts serve to arrest splitting cracks and increase local confinement and shear transfer from the bar to surrounding concrete. This effectively translates into higher concrete-steel bond strength and a reduction in the anchorage length required to develop the tensile strength of the reinforcement inside the ducts. Read the entire page →
From page 104... ... NCHRP Project 12-102 104 0 5 10 15 20 25 30 35 40 4 5 6 7 8 9 10 11 12 13 14 15 l ac /d bl f'cg (ksi) Read the entire page →
From page 105... ... NCHRP Project 12-102 105 Figure 5.5.3.15-3 Technology Readiness Evaluation for Article 3.6.5.1 Read the entire page →
From page 106... ... NCHRP Project 12-102 106 5.5.3.16 Article 3.6.5.2 Splicing of Longitudinal Reinforcement The requirements proposed in this section already exist in AASHTO LRFD Bridge Design Specifications (2014) as "Splices of Bar Reinforcement". Read the entire page →
From page 107... ... NCHRP Project 12-102 107 Figure 5.5.3.16-1 Technology Readiness Evaluation for Article 3.6.5.2 Read the entire page →
From page 108... ... NCHRP Project 12-102 108 5.5.3.17 Article 3.6.5.3 Debonding of Column Longitudinal Reinforcement This article is intended to provide the designer with an optional detail for improved seismic behavior of the column-to-pier cap or column-to-footing connection with grouted ducts. Laboratory tests have on column-to-cap and column-to-footing connections have shown that debonding may prevent premature bar fracture, reduce spalling of capacity-protected elements, and delay cyclic strength degradation (Mashal et al. Read the entire page →
From page 109... ... NCHRP Project 12-102 109 Figure 5.5.3.17-1 Technology Readiness Evaluation for Article 3.6.5.3 Read the entire page →
From page 110... ... NCHRP Project 12-102 110 5.5.3.18 Article 3.6.5.4 Bedding Layer Multiple precast connections reported in the literature incorporated the use of a bedding layer to facilitate construction of the test specimens (Belleri and Riva 2012; Mashal et al., 2014; Restrepo et al., 2011) Read the entire page →
From page 111... ... NCHRP Project 12-102 111 Because bedding layers have commonly used in the assembly of precast elements in the field and in experimental research, a high technology readiness score is assigned to this article. The following is a technology readiness form for this article: Figure 5.5.3.18-1 Technology Readiness Evaluation for Article 3.6.5.4 Read the entire page →
From page 112... ... NCHRP Project 12-102 112 5.5.3.19 Article 3.6.5.5 Development of Deformed Steel Bars in Corrugated Steel Ducts Using UHPC Provisions in Article 3.6.5.5 are based on design specifications and supporting research by Tazarv and Saiidi (2013) Read the entire page →
From page 113... ... NCHRP Project 12-102 113 5.5.3.20 Article 3.6.6 Pocket Connections Provisions in subsections of Article 3.6.6 are largely based on design specifications and supporting research included in NCHRP Report No. 681 (Restrepo et al., 2011) Read the entire page →
From page 114... ... NCHRP Project 12-102 114 As required with any of the connections listed in the proposed ABC Guide Specifications, the designer is responsible to identify the load path and provide proper detailing for force transfer from adjacent elements in accordance to AASHTO design provisions. For a pocket connections under an extreme condition in which the joint is cracked, for example, the load transfer mechanism may be as represented in Figure 5.5.3.20-2a with a simplified strut-and-tie model. Read the entire page →
From page 115... ... NCHRP Project 12-102 115 Figure 5.5.3.20-3 Technology Readiness Evaluation for Article 3.6.6.1 Read the entire page →
From page 116... ... NCHRP Project 12-102 116 5.5.3.21 Article 3.6.6.2 Formed Pocket and Fill The seismic performance of pocket connections for column-to-pier cap assemblies has only been assessed in laboratory tests involving the use lock-seam corrugated steel pipes to form the pockets (Restrepo et al., 2011; Mehrsoroush and Saiidi, 2014 & 2016, Wipf et al., 2009) Read the entire page →
From page 117... ... NCHRP Project 12-102 117 Figure 5.5.3.21-1 Technology Readiness Evaluation for Article 3.6.6.2 Read the entire page →
From page 118... ... NCHRP Project 12-102 118 5.5.3.22 Article 3.6.6.3 Minimum Development Length of Reinforcing Steel for SDCs C and D (Seismic Zones 3 and 4) The development equation in NCHRP Report No. Read the entire page →
From page 119... ... NCHRP Project 12-102 119 Equation (1) was not intended for seismic applications and so it produces a shorter development length compared to the other two expressions. Read the entire page →
From page 120... ... NCHRP Project 12-102 120 Figure 5.5.3.22-2 Technology Readiness Evaluation for Article 3.6.6.3 Read the entire page →
From page 121... ... NCHRP Project 12-102 121 5.5.3.23 Article 3.6.6.4 Corrugated Steel Pipe Thickness Requirements in this article are based on the recommendations given in NCHRP Report No. 681 (Restrepo et al., 2011) Read the entire page →
From page 122... ... NCHRP Project 12-102 122 ݐ௣௜௣௘ = thickness of corrugated steel pipe (in.) ߙ = angle between horizontal axis of receiving member and pipe helical corrugation or lock seam (deg) Read the entire page →
From page 123... ... NCHRP Project 12-102 123 Figure 5.5.3.23-2 Technology Readiness Evaluation for Article 3.6.6.4 Read the entire page →
From page 124... ... NCHRP Project 12-102 124 5.5.3.24 Article 3.6.6.5 Bedding Layer Multiple precast connections reported in the literature incorporated the use of a bedding layer to facilitate construction of the test specimens (Belleri and Riva 2012; Mashal et al., 2014; Restrepo et al., 2011) Read the entire page →
From page 125... ... NCHRP Project 12-102 125 Figure 5.5.3.24-1 Technology Readiness Evaluation for Article 3.6.6.5 Read the entire page →
From page 126... ... NCHRP Project 12-102 126 5.5.3.25 Article 3.6.6 Abutment-to-Pile Pocket Connections The provisions in this article are based on experimental research with scaled precast integral abutments conducted by Wipf et al., (2009) Read the entire page →
From page 127... ... NCHRP Project 12-102 127 Figure 5.5.3.25-1 Technology Readiness Evaluation for Article 3.6.6.6 Read the entire page →
From page 128... ... NCHRP Project 12-102 128 -10 -5 0 5 10 -400 -300 -200 -100 0 100 200 300 400 Drift [%] Read the entire page →
From page 129... ... NCHRP Project 12-102 129 Figure 5.5.3.26-2 Technology Readiness Evaluation for Article 3.6.7.1 Read the entire page →
From page 130... ... NCHRP Project 12-102 130 5.5.3.27 Article 3.6.7.2 Precast Concrete Column in Spread Footing or Pile Cap Socket Connection The seismic performance of socket connections for concrete column-to-spread footings have been extensively studied over the last two decades through laboratory testing and finite element modeling (Osanai et al., 1996, Motaref et al., 2011, Haraldsson et al., 2013a and 2013b, Belleri and Riva 2012, Mashal et al., 2014) Read the entire page →
From page 131... ... NCHRP Project 12-102 131 Embedded ColumnCIP Footing cDc Dc Figure 5.5.3.27-1 Precast Column with CIP Footing Figure 5.5.3.27-2 Vertical Equilibrium of Embedded Portion of PC Column in CIP Footing- Cohesion Only • If the column embedment is less than 1.5Dc, then an intentionally roughened surface is required according to the proposed guide specification. For a circular column that is embedded Dc into the footing (minimum allowed) Read the entire page →
From page 132... ... NCHRP Project 12-102 132 P CC T T For concrete placed against clean concrete but not intentionally roughened, AASHTO LRFD Bridge Design Specification (2014) allows to use c = 0.075 ksi (less than ܭଵ ௖݂ᇱ = 0.2 ௖݂ᇱ and ܭଶ = 0.8 ݇ݏ݅) Read the entire page →
From page 133... ... NCHRP Project 12-102 133 But equilibrium of the footing section at the interface with the column requires that ܥ = ܣ௦ ௬݂ so the shear friction capacity provided by the footing bottom reinforcement ܣ௦ becomes: ܲ = 2ߤ(ܣ௦ ௬݂) Read the entire page →
From page 134... ... NCHRP Project 12-102 134 Figure 5.5.3.27-4 Technology Readiness Evaluation for Article 3.6.7.2 Read the entire page →
From page 135... ... NCHRP Project 12-102 135 5.5.3.28 Article 3.6.7.3 Precast Concrete Column in Oversized Cast-in-Place Concrete Shaft Socket Connection This connection is an extension of the "wet socket" concept alluded in Article 3.6.7.2 but applicable to deep foundations. Provisions in this article are mostly taken from the design specifications included in report FHWA-HIF-13-037A (Marsh et al., 2013b) Read the entire page →
From page 136... ... NCHRP Project 12-102 136 Figure 5.5.3.28-1 Confinement Reinforcement for Column Embedded in Oversized Shaft Different values of the efficiency factor, k, are specified for the lower and upper half of the embedded portion of the splice zone. The amount of spiral in the upper half (k = 1) Read the entire page →
From page 137... ... NCHRP Project 12-102 137 Equaling the right sides of Equations (5.5.3.28-1) Read the entire page →
From page 138... ... NCHRP Project 12-102 138 In which ௦ܰ௛ = number of shaft longitudinal bars; ܦ௘௫௧ =diameter of shaft transverse spiral or hoops; ߝ௬௧௥ =yield strain of transverse reinforcement; ܦ௦ =diameter of steel casing; ߝ௬,௖ =yield strain of casing steel. The publication of Eq. Read the entire page →
From page 139... ... NCHRP Project 12-102 139 Figure 5.5.3.28-2 Technology Readiness Evaluation for Article 3.6.7.3 Read the entire page →
From page 140... ... NCHRP Project 12-102 140 5.5.3.29 Article 3.6.7.4 Precast Concrete Column in Precast Pier Cap Socket Connection The seismic performance of socket connections in precast elements has been assessed through multiple monotonic cyclic load testing of scaled assemblies. In order to form the socket of column-to-pier cap connections, Mehrsoroush and Saiidi (2014) Read the entire page →
From page 141... ... NCHRP Project 12-102 141 The following is a technology readiness form for this article. Laboratory testing at the assembly level together with field implementation and developed design recommendations and provisions result in a high score for technology readiness. Read the entire page →
From page 142... ... NCHRP Project 12-102 142 Annular Plate (welded) CIP FOOTING ݈௘ 8t 8t Tube Thickness (t) Read the entire page →
From page 143... ... NCHRP Project 12-102 143 Source: Stephens et al., (2013) Figure 5.5.3.30-2 Column Base Moment versus Drift Response of CFST-Footing Socket Connections with Different Embedment Depths The required embedment depth, ݈௘, of the CFST depends on whether yielding or plastic moment strength of the CFST is to be developed. Read the entire page →
From page 144... ... NCHRP Project 12-102 144 Plastic Neutral Axis Fy Fy 0.95f'c Concrete Stress Steel Stress Equilibrium Acc Asc Ast Cc =0.95f'cAcc Cs =FyAsc Ts =FyAst Py ݒ௡ = 0.19ට ௖݂௙ᇱ (in ksi units) as illustrated in Figure 5.5.3.30-3. Read the entire page →
From page 145... ... NCHRP Project 12-102 145 45o Figure 5.5.3.30-4 Simplified Pullout Model for CSFT Figure 5.5.3.30-5 Reinforcement Detail at CFST-to-Footing Connection Detailing requirements for load transfer across the joint of the CFST socket connection (Figure 5.5.3.30-5) are not explicitly provided by Stephens et al. Read the entire page →
From page 146... ... NCHRP Project 12-102 146 study it was concluded that a properly detailed pier cap with a width as narrow as 2.0 times the tube diameter is sufficient to develop the plastic moment capacity of the CFST. • Vertical ties must be placed in the region of the connection within a distance 1.5݈௘ from the outside of the CFST at spacing ݏ satisfying: ݏ ≤ ௟೐ଶ.ହ (5.5.3.30-5) Read the entire page →
From page 147... ... NCHRP Project 12-102 147 5.5.3.31 Article 3.6.8 Full-Depth Precast Concrete Deck Panel Connections Section 4.2.1 of this report describes in detail the various research projects that have been undertaken regarding full-depth precast concrete deck panels. The research to date on precast concrete deck panels is more significant than any other type of prefabricated element. Read the entire page →
From page 148... ... NCHRP Project 12-102 148 Figure 5.5.3.31-1 Technology Readiness Evaluation for Article 3.6.8 Read the entire page →
From page 149... ... NCHRP Project 12-102 149 5.5.3.32 Article 3.6.9 Link Slabs Section 4.2.1 of this report describes in detail the various research projects that have been undertaken regarding link slabs. The basis of the provisions for the Guide Specification is the PCI Journal article entitled "Behavior and Design of Link Slab for Jointless Bridge Decks (Caner, et al., 1998) Read the entire page →
From page 150... ... NCHRP Project 12-102 150 Figure 5.5.3.32-1 Technology Readiness Evaluation for Article 3.6.9 Read the entire page →
From page 151... ... NCHRP Project 12-102 151 5.5.3.33 Article 3.6.10 Steel Connections At this time, there are no special methods for connecting steel elements. Connections are made with either bolting or welding. Read the entire page →
From page 152... ... NCHRP Project 12-102 152 5.5.3.35 Article 3.6.12 Two-Stage Integral Pier Cap Figure 5.5.3.35-1 illustrates the two-stage integral pier cap system. This article refers to the design of a force transfer mechanism between the dropped cap beam and the upper superstructure diaphragm. Read the entire page →
From page 153... ... NCHRP Project 12-102 153 Figure 5.5.3.35-2 Technology Readiness Evaluation for Article 3.6.12 Read the entire page →
From page 154... ... NCHRP Project 12-102 154 5.5.3.36 Article 3.6.12.1 Joint Proportioning for Two-Stage Integral Pier Cap for SCDs C and D or Seismic Zones 3 and 4 The requirements in this article are nearly identical to the "Joint Design for SDCS C and D" provisions outlined in AASHTO Guide Specifications for LRFD Seismic Bridge Design (1) with the exception that the provisions are extended to force-based design in Seismic Zones 3 and 4. Read the entire page →
From page 155... ... NCHRP Project 12-102 155 Figure 5.5.3.36-2 Critical Area for the Calculation of fv for Seismic Excitation in the Longitudinal Direction of the Bridge Figure 5.5.3.36-3 Critical Area for the Calculation of vjv for Seismic Excitation in the Longitudinal Direction of the Bridge Read the entire page →
From page 156... ... NCHRP Project 12-102 156 Figure 5.5.3.36-4 Critical Area for the Calculation of fh for Seismic Excitation in the Transverse Direction of the Bridge Figure 5.5.3.36-5 Critical Area for the Calculation of fv for Seismic Excitation in the Transverse Direction of the Bridge Ds2 Ds1 Dc Bcap Read the entire page →
From page 157... ... NCHRP Project 12-102 157 Figure 5.5.3.36-6 Critical Area for the Calculation of vjv for Seismic Excitation in the Transverse Direction of the Bridge The following is a technology readiness form for this article. A high score is assigned because the system is widely used and because only modifications to existing AASHTO joint average stress equations are being proposed for consistency with the load paths in each direction of analysis. Read the entire page →
From page 158... ... NCHRP Project 12-102 158 Figure 5.5.3.36-7 Technology Readiness Evaluation for Article 3.6.12.1 Read the entire page →
From page 159... ... NCHRP Project 12-102 159 5.5.3.37 Article 3.6.12.2 Minimum Joint Shear Reinforcing for SDCs C and D or Seismic Zones 3 and 4 The requirements in this article are nearly identical to the "Minimum Joint Shear Reinforcing" provisions outlined in AASHTO Guide Specifications for LRFD Seismic Bridge Design (1) with the exception that for joints in which the calculated principal tension exceeds the cracking limit of 0.11ඥ ௖݂ᇱ the designer should select the maximum transverse reinforcement ratio (in the horizontal plane) Read the entire page →
From page 160... ... NCHRP Project 12-102 160 Figure 5.5.3.37-1 Technology Readiness Evaluation for Article 3.6.12.2 Read the entire page →
From page 161... ... NCHRP Project 12-102 161 5.5.3.38 Article 3.6.12.3 Superstructure Capacity Design for Two-Stage Integral Pier Caps for Longitudinal Direction for SDCs C and D The requirements in this article are nearly identical to the "Superstructure Capacity Design for Integral Bent Caps for Longitudinal Direction for SDCs C and D" provisions outlined in AASHTO Guide Specifications for LRFD Seismic Bridge Design (1) with the exception that the effective width of the superstructure resisting longitudinal seismic moments is revised, as shown in Figure 5.5.3.38-1, for open soffit girder-deck superstructures with integral dropped cap beam. Read the entire page →
From page 162... ... NCHRP Project 12-102 162 Figure 5.5.3.38-2 Technology Readiness Evaluation for Article 3.6.12.3 Read the entire page →
From page 163... ... NCHRP Project 12-102 163 5.6 Section 4 – Detailing Requirements This section includes recommendations for general detailing requirements for ABC designs using prefabricated elements. There are several sources for the provisions in this section: 1. Read the entire page →
From page 164... ... NCHRP Project 12-102 164 5.7 Section 5 – Durability of ABC Technologies This section includes recommendations for detailing and design for durability. There are several sources for the provisions in this section: 1. Read the entire page →

From page 58...

... NCHRP Project 12-102 58 C H A P T E R 5 ABC Design Specification Development 5.1 Approach This project is essentially a large-scale synthesis of past work. No formal laboratory research was completed under this project.