1、BLAST TESTING OF PRESTRESSED CONCRETE UNDER IMPULSIVE LOADINGSTP-NU-083STP-NU-083 BLAST TESTING OF PRESTRESSED CONCRETE UNDER IMPULSIVE LOADING Prepared by: K. El-Domiaty, Stone Security Engineering, PC J. Florek, Stone Security Engineering, PC ii Date of Issuance: June 30, 2017 This report was prep
2、ared by ASME Standards Technology, LLC (“ASME ST-LLC”) and jointly sponsored by the Canadian Nuclear Safety Commission (“CNSC”), Daewoo Institute of Construction Technology (“DICT”), Electricity of Frances Department of Thermal and Nuclear Studies and Projects (“EDF/SEPTEN”), the Swiss Federal Nucle
3、ar Safety Inspectorate (“ENSI”), the French Nuclear Safety Authoritys Institute for Radiological Protection and Nuclear Safety (“IRSN”), the Finland Radiation and Nuclear Safety Authority (“STUK”), and the American Society of Mechanical Engineers (“ASME”) Nuclear Codes and Standards. Neither ASME, A
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10、roduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. ASME Standards Technology, LLC Two Park Avenue, New York, NY 10016-5990 ISBN No. 978-0-7918-7166-9 Copyright 2017 by ASME Standards Technology, LLC All Rights Reserved STP-NU-0
11、83: Blast Testing of Prestressed Concrete Under Impulsive Loading iii TABLE OF CONTENTS Foreword vi Executive Summary . vii 1 Introduction 1 2 Stone-OBL Blast Testing Site 2 2.1 Site Layout . 2 2.2 Reaction Structure 4 3 Test Specimens . 5 3.1 Post-Tensioned Strand Stress Level . 5 3.2 Mild Steel Re
12、inforcement Level and Slab Construction . 6 3.3 Supporting Steel Frame Construction and Panel Installation 7 4 Open-Air Blast Testing Procedure . 12 4.1 Instrumentation and Test Documentation 12 4.2 Explosives and Test Matrix . 19 4.3 Pre-Stressed Concrete Slab Response Limits 20 5 Test Results 22 5
13、.1 Test 1 (Panel 5A) . 23 5.2 Test 2 (Panel 1A) . 25 5.3 Test 3 (Panel 2C) . 28 5.4 Test 4a (Panel 6C) 30 5.5 Test 4b (Panel 6C) . 32 5.6 Test 5 (Panel 7B) . 33 5.7 Test 6 (Panel 3B) . 35 5.8 Test 7 (Panel 4D) . 38 5.9 Test 8 (Panel 8D) . 39 6 Conclusions 42 Appendix A: Calculations and Drawings . 4
14、3 Appendix B: VSL Stressing Protocols, Data, and Certification 50 Appendix C: Slab Inspection and Concrete Results 89 Appendix D: Instrumentation Calibration Certification 102 Appendix E: Test Results Documentation . 172 LIST OF FIGURES Figure 2-1: Site Location 2 Figure 2-2: Site Layout . 3 Figure
15、2-3: Mud Mat Construction . 3 Figure 2-4: Reaction Structure 4 Figure 3-1: Test Specimen Summary . 5 Figure 3-2: Slab Observed during Inspection Site Visit 5 Figure 3-3: Concrete Crushing Test Summary 7 Figure 3-4: Sketches of Simple Supports Used in Test 1 and Test 2 . 7 Figure 3-5: Steel Pedestals
16、 Used in Test 1 and Test 2 . 8 Figure 3-6: Lifting of Slab with Crane for Installation onto the Test Fixture (Framing Set-Up 1) . 8 STP-NU-083: Blast Testing of Prestressed Concrete Under Impulsive Loading iv Figure 3-7: Installed Panel within Framing Set-Up 1 . 8 Figure 3-8: Steel Framing Set-Up 2
17、Layout (Isometric View) 9 Figure 3-9: Steel Framing Set-Up 2 Layout (Section View) . 10 Figure 3-10: Steel Framing Set-Up 2 Pedestal (Isometric View) 10 Figure 3-11: Lifting of Slab with Crane for Installation onto the Test Fixture (Framing Set-Up 2) . 11 Figure 3-12: Installed Panel within the Stif
18、fer Framing Set-Up 2 . 11 Figure 4-1: Examples of Strain Gauge Attachment to Rebar 12 Figure 4-2: Standard Strain Gauge Locations 13 Figure 4-3: Standard Strain Gauge Location Schedule 14 Figure 4-4: Strain Gauges with Open or Short Circuits . 14 Figure 4-5: Data Channels for Strain Gauges and Displ
19、acement Sensors . 15 Figure 4-6: Pre-Test Laser Locations on Interior Slab Face 16 Figure 4-7: Displacement and Pressure Sensor Locations for Test 1 and Test 2 . 17 Figure 4-8: Displacement and Pressure Sensor Locations for Test 3 through Test 8 18 Figure 4-9: Reflected Pressure Sensor Locations for
20、 Test 3 through Test 8 19 Figure 4-10: Test Matrix 20 Figure 4-11: Flexural Response Limits for Pre-Stressed Concrete Slabs 20 Figure 4-12: Damage Levels 21 Figure 5-1: Test Results Summary. 22 Figure 5-2: Pre-Test Photos of Test 1 23 Figure 5-3: Front Face Slab Scabbing in Test 1 . 23 Figure 5-4: B
21、ack Face Slab Cracking in Test 1 (at Bottom Center) 24 Figure 5-5: Through-Thickness Slab Cracking in Test 1 (at Bottom Left) 24 Figure 5-6: Steel Frame Damage in Test 1 (at Upper Left and Upper Right Corners) 25 Figure 5-7: Pre-Test Photos of Frame Modifications for Test 2 25 Figure 5-8: Pre-Test P
22、hotos of Test 2 26 Figure 5-9: Front Face Slab Scabbing in Test 2 . 26 Figure 5-10: Back Face Slab Cracking in Test 2 (Overall and Along Left Edge) . 27 Figure 5-11: Through-Thickness Slab Cracking in Test 2 . 27 Figure 5-12: Steel Frame Damage in Test 2 (Along Upper Edge) 28 Figure 5-13: Pre-Test P
23、hotos of Test 3 28 Figure 5-14: Post-Test Photos of Test 3. 29 Figure 5-15: Highlighted Cracking Pattern on Back Face in Test 3 29 Figure 5-16: Through-Thickness Cracking along Top and Side Edges in Test 3 30 Figure 5-17: Disengagement of Concrete Layers in Test 3 . 30 Figure 5-18: Pre-Test Photos o
24、f Test 4a 31 Figure 5-19: Post-Test Photos of Test 4a . 31 Figure 5-20: Front Face Slab Scabbing in Test 4b . 32 Figure 5-21: Highlighted Cracking Pattern on Back Face in Test 4b 33 Figure 5-22: Through-Thickness Cracking along Side Edge in Test 4b 33 Figure 5-23: Pre-Test Photos of Test 5 34 Figure
25、 5-24: Front Face Slab Scabbing in Test 5 . 34 Figure 5-25: Highlighted Cracking Pattern on Back Face in Test 5 . 35 Figure 5-26: Through-Thickness Cracking along Side Edge in Test 5 . 35 Figure 5-27: Pre-Test Photos of Test 6 36 Figure 5-28: Front Face Slab Scabbing in Test 6 . 36 Figure 5-29: Crac
26、king Pattern on Back Face in Test 6 37 Figure 5-30: Through-Thickness Cracking along Side Edge in Test 6 37 Figure 5-31: Pre-Test Photos of Test 7 38 Figure 5-32: Post-Test Photos of Test 7. 39 Figure 5-33: Through-Thickness Cracking along Side Edge in Test 7 39 STP-NU-083: Blast Testing of Prestres
27、sed Concrete Under Impulsive Loading v Figure 5-34: Pre-Test Photos of Test 8 40 Figure 5-35: Front Face Slab Scabbing in Test 8 . 40 Figure 5-36: Cracking Pattern on Back Face in Test 8 41 Figure 5-37: Through-Thickness Cracking along Side Edge in Test 8 41 STP-NU-083: Blast Testing of Prestressed
28、Concrete Under Impulsive Loading vi FOREWORD This publication was prepared by ASME ST-LLC and jointly sponsored by the CNSC, DICT, EDF/SEPTEN, the ENSI, the IRSN, the STUK, and the ASME. The test program, including the design and fabrication of the prestressed test slabs, was conducted by Stone Secu
29、rity Engineering, PC (“SSE”) and at the open-air blast test site managed by Oregon Ballistic Laboratories, LLC (“OBL”) and Stone-OBL, LLC (“SOBL”) of Salem, Oregon, United States of America (U.S.A.). Established in 1880, the ASME is a professional not-for-profit organization with more than 135000 me
30、mbers and volunteers promoting the art, science and practice of mechanical and multidisciplinary engineering and allied sciences. ASME develops codes and standards that enhance public safety, and provides lifelong learning and technical exchange opportunities benefiting the engineering and technolog
31、y community. Visit www.asme.org for more information. ASME ST-LLC is a not-for-profit Limited Liability Company, with ASME as the sole member, formed in 2004 to carry out work related to new and developing technology. The ASME ST-LLC mission includes meeting the needs of industry and government by p
32、roviding new standards-related products and services, which advance the application of emerging and newly commercialized science and technology and providing the research and technology development needed to establish and maintain the technical relevance of codes and standards. Visit (http:/asmestll
33、c.org/) for more information. STP-NU-083: Blast Testing of Prestressed Concrete Under Impulsive Loading vii EXECUTIVE SUMMARY This report provides the background, test set-up information, and results for the open-air blast testing of eight simply supported, two-way, precast prestressed/post-tensione
34、d concrete slabs with varying conventional reinforcement and prestressing/ post-tensioned levels. The slabs in the main portion of the testing program sustained support rotations ranging from 0.4 degrees to 3.0 degrees. The corresponding damage level for these tests would roughly range from “Superfi
35、cial Damage” to “Heavy Damage” as defined in Canadian Standards Association (“CSA”) standard S850-12, “Design and Assessment of Buildings Subjected to Blast Loads,” and the American Society of Civil Engineers (“ASCE”) standard 59-11, “Blast Protection of Buildings.” However, from the extent of concr
36、ete disengagement observed in Test 3, it would appear that a 3.0-degree rotation is approaching the post-tensioned slabs upper limit state for non-hazardous damage (i.e., near a transition from “Heavy Damage” to “Hazardous Damage” as defined in the previously-referenced standards). The test results
37、seem to indicate that the actual response limits would fall between the currently published limits for prestressed concrete (lower bound) and conventionally reinforced concrete (upper bound) elements. Moreover, comparing the results for tests on slabs subjected to a similar blast threat, it appears
38、that the increase of pre-stressing level from 725 pounds per square inch (psi) (5 megapascals (MPa) to 1450 psi (10 MPa) may only have a marginal effect on slab flexural response to blast loading. Additional testing and/or detailed analysis that can account for concrete disengagement, as well as she
39、ar and/or concrete-crushing controlled behavior (e.g., finite element modeling), should be performed to justify any modification to the currently published response limits and further examine the effects of prestressing/post-tensioning in blast applications. STP-NU-083: Blast Testing of Prestressed
40、Concrete Under Impulsive Loading 1 1 INTRODUCTION Considering the properties of prestressing steel and the level of compression in concrete, prestressed concrete members should respond with lower deflections under blast loading than similarly-sized, conventionally reinforced members. However, the av
41、ailable acceptance criteria for prestressed concrete in typical structures, provided in CSA standard S850-12, “Design and Assessment of Buildings Subjected to Blast Loads,” ASCE standard 59-11, “Blast Protection of Buildings,” and the Precast/Prestressed Concrete Institute (“PCI”) Blast-Resistant De
42、sign Manual, First Edition are significantly more stringent than for conventionally reinforced concrete. The technical basis for the difference is unclear. Therefore, given the number of existing prestressed concrete containment structures and new builds of similar construction anticipated in Canada
43、, the U.S.A., and worldwide, there is a need to define design provisions for prestressed concrete elements with all specificities of nuclear structures (e.g., reinforcement ratio and detailing, prestressing level) which could potentially use more relaxed acceptance criteria than for typical structur
44、es, if warranted. This information would be beneficial for vendors, designers, regulators, and standards development organizations worldwide. This research project proposal originated from a joint task group of three different standards committees: Joint ACI-ASME Committee on Concrete Components for
45、 Nuclear Service (BPVC Section III Division 2/ACI 359), ACI 349 (Concrete Nuclear Structures), and ACI 370 (Blast and Impact Load Effects). Toward that objective, sponsors from industry, regulatory agencies, and standards developing organizations, which have a direct interest in nuclear structures,
46、provided the sponsorship funds for this research project to test prestressed concrete slabs under blast loading. This research project was managed by ASME ST-LLC. ASME ST-LLC tasked SSE to perform a series of blast tests on simply supported, twoway prestressed concrete slabs to achieve a range of re
47、sponses based on the research proposal from the ASME Special Working Group of Modernization reporting to the Joint ACI-ASME Committee on Concrete Components for Nuclear Service (BPV III). The eight slab specimens were 10-5/8 inches (270 millimeters (mm) 16 feet (ft) (4880 mm) 16 feet (4880 mm) in di
48、mensions. Two layers of conventional flexural reinforcement and local shear reinforcement around lifting points were included in each slab. Prestressing in the concrete was introduced using post-tensioned (PT) tendons. The parameters that varied were the pressure loading, conventional reinforcement
49、ratio, and level of prestressing. This publication provides the background for the open-air blast testing of the precast, prestressed slabs, and summarizes results for a total of nine blast tests performed on the eight slabs. An overview of the testing facility is provided in Section 2. A description of the test specimen and supporting steel frame construction is provided in Section 3. The open-air testing procedure, including instrumentation, explosive material and quantities used, and documentation recorded, and relevant prestressed concrete slab response limits are discussed in
