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مبادرة
#تواصل_تطوير
المحاضرة الثانية والأربعون من المبادرة مع
الأستاذ الدكتور/ مدحت كمال عبدالله
استاذ هندسة الجسور كلية هندسة المطرية جامعة حلوان
بعنوان
أسباب إنهيار الجسور-تطبيقات عملية
Failure of Bridges-Case Studies
التاسعة مساء توقيت مكة المكرمةالأربعاء12أغسطس2020
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4. • Why we need Bridges
• Who is involved in the decision and design of a bridge
• Statistical analysis of failure cases
• Common Causes of Failure:
• Highway Planning
• Concrete strength
• Prestressing
• Bearings and Expansion Joints
• Nature: Earthquakes, Fires, Pollution…etc.
• BOMB ATTACK
• Overloading
CONTENTS:
19. Analysis of Recent Bridge Failures in the United States
• Over 500 failures of bridge structures in the United States between 1989 and 2000
were studied.
• The age of the failed bridges ranged from 1 year ~during construction! to 157 years,
with an average of 52.5 years.
• The most frequent causes of bridge failures were attributed to floods and collisions
almost 53% of all failures!.
• Bridge overload and lateral impact forces from trucks, barges/ships, and trains
constitute 20% of the total bridge failures. Other frequent principal causes are
design, detailing, construction, material, and maintenance.
• Comparison made among three periods of similar studies ~1977–1981, 1982–1988,
and 1989–2000! revealed almost similar trends, with most failures occurring during
the bridge’s service life. Also, human-induced external events occurred frequently in
all three periods, but were most dominant in the first and third periods.
Technological advances in information systems have a great impact on data
collection and analysis.
20.
21.
22.
23.
24. Lifetime of Bridge Elements
• 6 -10 years for roadway pavement;
• 2 - 4 years for expansion joints;
• 7 - 10 years for water insulation;
• 50-60 years for piled piers.
30. Assessment of the damage caused at
horizontally curved segmental bridge deck
31. Assessment of the damage caused at horizontally curved segmental bridge deck
32.
33.
34.
35.
36. Picture 5: Splitting of Concrete Picture 6: Delamination of concrete
Picture 8: Delamination and crushing of concrete
Picture 7: Splitting of concrete
43. :
مالحظات:
1-عنه يدافع اخر اجنبي مكتب أحضر التحقيقات وعند عالمي ومكتب أجنبي األستشاري
2-لألعتماد تنفيذية لوحات يراجعهاويقدم أن وعليه أبتدائية الرسومات ان به ذكر المقاول عقد
3-التنفيذية الرسومات عن يسال ان بدون التنفيذ على وافق األستشاري
4-نفقته على األصالحات بعمل المقاول وقام المطلوب التسليح واضافة الرسومات تعديل تم
According to the Contract
Executive Drawings
• The Contract Drawings contain only the basic details and show the general features that are
necessary to give a comprehensive idea of the construction. All construction features i.e. roadway
alignment, profile grade, typical sections, pavement, locations and size of drainage structure, details,
and dimensions of all structural elements, reinforcement details, protection works and other ancillary
item are all shown on the Drawings.
•
• The Contractor shall prepare, thoroughly check and submit to the Engineer for his approval,
sufficiently in advance; all executive drawings as may be required to show in detail all parts of the
permanent works. These drawings shall include but not limited to shop detail drawings, bar bending
schedules and concrete structures, and also plan profile drawings and cross sections following a joint
survey readings on the Site inclusive of
44.
45. • THE DESIGNER IS INTERNATIONAL EUROPEAN
• THE CONTRACTOR IS INTERNATIONAL
• WEAK OWNER
• THE CONSTRUCTION STARTED WITHOUT REVIEWING THE DESIGN
112. Steel Rocker Type Bearing Defects: Bearing Out of Vertical at 70° F
CAUSES
Abutment moving inward due to pavement pressure or foundation settlement
Unequal bearing pressure of all bearings
Collision damage of pier
113.
114. Steel Rocker Type Bearing Defects: Corrosion of Steel
Corroded bearing RECOMMENDED REPAIRS
· Seal expansion joints and spot paint
bearing
CAUSES
Leaking expansion
joints/debris on abutment sea
128. Strip Seal Expansion Joint Defects: Joint Leaking
Loose seal
CAUSES
Seal punctured or pulled out of
anchorage
RECOMMENDED REPAIRS
· Remove and reinstall new gland
Joint Leaking
129. Debris Lodged in Sliding
Plate Joint
Dirt in a Compression
Seal Joint