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From page 189... ... G-1 APPENDIX G: Evaluation of Proposed Simplified Provisions with Selected Shear Database In this appendix, the proposed simplified shear design provisions are evaluated and validated using with test data. In Section G.1, the overall performance and safety of the proposed simplified provisions (Vtest/Vprop) Read the entire page →
From page 190... ... G-2 By contrast with the AASHTO STD results, use of the LRFD shear design specifications results in strength predictions, Fig. G-2, that provide safe and accurate estimates of measured capacities for both RC and PC members, with no observable trends for the four selected test parameters. Read the entire page →
From page 191... ... G-3 In order to appreciate the basis for the selection of the proposed cwV expression, it is useful to examine the scatter in the shear strength of PC members without shear reinforcement, vA . In such tests, the ultimate capacity is directly dependent on cV and, based on observations, that capacity typically occurs shortly after diagonal cracking has developed. Read the entire page →
From page 192... ... G-4 with an average ratio, , ,/cr test cr STDV V , of 1.15. The calculated cracking strengths using the proposed simplified approach are very conservative with an average ratio, , ,/cr test cr PropV V , of 1.70. Read the entire page →
From page 193... ... G-5 that cracking. Twelve test results from six girders were available at the time this report was written. Read the entire page →
From page 194... ... G-6 Table G-1 Database of Selected Reinforced Concrete Members (64 Members) Reference Beam shape f'c d bw a/d Loading ρl ρvfy Vtest* Read the entire page →
From page 195... ... G-7 Table G-2 Database of Selected Prestressed Concrete Members (83 Members) Reference Beam shape f'c d bw a/d Loading ρpl fpe ρvfy Vtest* Read the entire page →
From page 196... ... G-8 Table G-3 Comparison of Strength Ratios for Major Codes and Proposed Approach Ratio of 64 RC members 83 PC members Ratio of VTest / VTest / VTest / VTest / VTest / VTest / VTest / VTest / VTest/VPred VSTD VLRFD VCSA VProp VSTD VLRFD VCSA VProp # of Beams 64 64 64 64 83 83 83 83 Mean 1.296 1.214 1.105 1.309 1.322 1.227 1.245 1.542 STDEV 0.431 0.217 0.172 0.291 0.211 0.177 0.167 0.292 COV 0.333 0.179 0.156 0.222 0.160 0.145 0.134 0.189 Distribution (%) Read the entire page →
From page 197... ... G-9 Table G-4 Web-Shear Cracking Strengths of NCHRP Project 12-56 Girders Test Specimen ' cf (psi) Read the entire page →
From page 198... ... G-10 Table G-6 Comparison of Flexure-Shear Cracking Strengths and Simplified Approach Predictions Test Results Simplified Proposal Test Specimen ' cf (ksi) Read the entire page →
From page 199... ... G-11 Statistical Values Vtest/Vn,STD N of Beams 64 Average 1.296 Stdev 0.431 COV 0.333 Statistical Values Vtest/Vn,STD N of Beams 83 Average 1.322 Stdev 0.211 COV 0.160 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 5000 10000 15000 20000 f'c (psi) Read the entire page →
From page 200... ... G-12 Statistical Values Vtest/Vn,LRFD N of Beams 64 Average 1.214 Stdev 0.217 COV 0.179 Statistical Values Vtest/Vn,LRFD N of Beams 83 Average 1.227 Stdev 0.177 COV 0.145 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 5000 10000 15000 20000 f'c (psi) Read the entire page →
From page 201... ... G-13 Statistical Values Vtest/Vn,CSA N of Beams 64 Average 1.105 Stdev 0.172 COV 0.156 Statistical Values Vtest/Vn,CSA N of Beams 83 Average 1.245 Stdev 0.167 COV 0.134 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 5000 10000 15000 20000 f'c (psi) Read the entire page →
From page 202... ... G-14 Statistical Values Vtest/Vn,Prop N of Beams 64 Average 1.309 Stdev 0.291 COV 0.222 Statistical Values Vtest/Vn,Prop N of Beams 83 Average 1.542 Stdev 0.292 COV 0.189 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 5000 10000 15000 20000 f'c (psi) Read the entire page →
From page 203... ... G-15 0.60.50.40.30.20.10 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 4 8 12 16 20 min~200 200~400 400~600 600~800 800~1000 >1000 ' ( ) pc c f ksi units f ' ( ) Read the entire page →
From page 204... ... G-16 0 0.1 0.2 0.3 0.4 0.5 0.6 0.0 4.0 8.0 12.0 16.0 20.0 0 4 8 12 16 20 min~200 200~400 400~600 600~800 800~1000 >1000 ' ( ) pc c f ksi units f ) Read the entire page →
From page 205... ... G-17 midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 605550454035 G1E Load: 15.2 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G1W Load: 18.7 kip/ft midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G2E Load: 18.7 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G2W Load: 21.7 kip/ft midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G3E Load: 16.17 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G3W Load: 14.92 kip/ft Figure G-8 Web-Shear Cracks for NCHRP 12-56 Girder Tests Read the entire page →
From page 206... ... G-18 midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G4E Load: 14.01 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G4W Load: 17.68 kip/ft midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G5E Load: 16.8 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G5W Load: 12.2 kip/ft midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G6E Load: 16.53 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G6W Load: 17.27 kip/ft Figure G-8 Cont'd. Read the entire page →
From page 207... ... G-19 0 0.1 0.2 0.3 0.4 0.5 0.6 0.0 1.0 2.0 3.0 4.0 5.0 6.0 0 4 8 12 16 20 min~200 200~400 400~600 600~800 800~1000 >1000 ' ( ) pc c f ksi units f ' ( ) Read the entire page →
From page 208... ... G-20 Total Length = 52 ft CL 31 spacings @ 10" = 310" 2" G1E Load: 23.5 kip/ft Total Length = 52 ft CL 31 spacings @ 10" = 310"2" G1W Load: 23.5 kip/ft 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 CL G2E Load: 25.9 kip/ft 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 CL G2W Load: 25.9 kip/ft midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G3E Load: 28.2 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G3W Load: 28.2 kip/ft Figure G-10 Flexure-Shear Cracks for NCHRP 12-56 Girder Tests Read the entire page →
From page 209... ... G-21 midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G4E Load: 30.7 kip/ft midspan 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 331 2 3 4 G4W Load: 30.7 kip/ft ~ 34.0 kip/ft : value used 32.0 kip/ft midspan 60 61 62 6355 56 57 58 5950 51 52 53 5449484746454443424140393837363534333231 G5E Load: 18.2 kip/ft Figure G-10 Cont'd Read the entire page →

From page 189...

... G-1 APPENDIX G: Evaluation of Proposed Simplified Provisions with Selected Shear Database In this appendix, the proposed simplified shear design provisions are evaluated and validated using with test data. In Section G.1, the overall performance and safety of the proposed simplified provisions (Vtest/Vprop)