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  1. This is most likely not a serious error; it will not have drastic effect on the behavior of the member. You might want to take a look at the hinge properties.
    2 points
  2. Sajjad

    My introduction

    Gentlemen, I just joined this esteemed forum. Let me introduce myself. I am a structural engineer have more that 35 years of experience in structural design. I have a YouTube Chanel also. Here is a link of one of my lectures. Please watch and send me your comments. Now I am working on designing the same building as per BCP-2021. Best Regards, Sajjad
    2 points
  3. Dear Waqar please check the pouring methodology and measures adopted to control temperature for mass concreting, if any. Then you can calculate the temperature rise during hardening of concrete and compare the difference of atmospheric temperature and concrete temperature. As very high cement content is anticipated so stringent temperature control requirements should have been adopted. By this you would be able to figure out whether these are temperature shrinkage cracks or otherwise. Moreover please calculate the crack width. As cover is high therefore there is a possibility that you may end up in calculating the crack width equivalent to whatever is visible there in the slab. Pattern of cracks you highlighted indicates the temperature shrinkage nature of cracks however calculations are needed to confirm the anticipation.
    2 points
  4. If leakage is a serious problem then a waterproof membrane is nearly always prescribed. If a little leakage is OK, then you might consider a perimeter drainage system around the tank and sump pit .
    2 points
  5. بسم الله الرحمن الرحيم I provided the book in three formats for easy access in the Google Drive links below The Full Book in a Single File: https://drive.google.com/file/d/1gSew3TaAPpEku3tW9fcC4QJ72PaVXBao/view?usp=sharing Separate Book Chapters Files: https://drive.google.com/drive/folders/1tueeYgieZx8zWMsmp3g1enoqPyna6Bp8?usp=sharing Separate Book Subtopic Files: https://drive.google.com/drive/folders/1ljDq3oRMWCaEz2x-QB5kVNB8GB32d0ke?usp=sharing Here is another link in Internet Archive https://archive.org/details/full-book-concrete-design-dr.-wael-hassan-2023 Preface I have been occupied for long time with the idea of writing a professional textbook on the design of concrete structures that presents this challenging subject in a simplified way, yet technically rigorous, accessible to most civil engineering students, even those not to specialize as structural engineers. I had intended that the book reflects my expertise in structural engineering, specifically concrete design, spanning more than 20 years of professional practice, research, and teaching. With that in mind, I developed over the years sets of lecture notes on reinforced concrete design that I used in various academic roles from teaching assistant to associate professor to teach undergraduate students in higher education institutions in the Middle East and North America This “book” is intended as a humble contribution in the field of structural design of reinforced concrete to make it more approachable, handy, and useful to undergraduate students and practicing structural engineers. It represents my set of lecture notes on concrete design developed over the period of eight years. However, most of the material presented, especially on the analysis and systems, can be useful in concrete design using any building code, with proper modifications according to local codes, since the theoretical basis used is common in many aspects among various codes My intent was to wait until I rewrite these lecture notes, with additional formal discussions, in a formal textbook format and assign a publisher to edit and disseminate that textbook professionally. However, given the substantial size of the material and my current academic and professional commitments, this project can take a few more years to be completed in the presentable way I envisioned. I felt guilty to hold back this knowledge further until formal publication although it can help many students and engineers until then, thus I am presenting these lecture notes as is with my handwriting and manual drawings in this “book,” with the intent of revising, upgrading and publishing it professionally in the future. Please refer to the remark in the Introduction chapter for details about the consistency of this book with the latest version of the Egyptian Code ECP 203-2020. The material in its current format is generally self-contained and it helped thousands of civil engineering students and practicing engineers learn concrete design successfully. I retain my publishing rights of this material for the sole intention of publishing the textbook in a more formal manner in the future; however, I grant the right to any individual to use the book for academic and educational purposes or professional design purposes without my permission. I further grant the right to any individual to post this material as is on the Internet and to distribute as is electronically or in print. The only restriction is to reproduce the material in part or whole in a different format without proper citation to use for commercial purposes without permission. Wael M. Hassan, Ph.D., P.E., S.E., F.ACI, F.ASCE, F.SEI Associate Professor of Structural Engineering TABLE OF CONTENTS PREFACE ACKNOWLEDGEMENT CHAPTER 1: Introduction Overview Organization of the "Book" CHAPTER 2: Design of Reinforced Concrete Beams Loads on RC Beams Loads on RC Beams Solved Problems Straining Actions/Internal Forces of RC Beams Fundamentals of Reinforced Concrete Design/Stages of Concrete Cracking Ultimate Limit State Design Method Ultimate Limit State Design Solved Problems Flexural Design of RC Beams Flexural Design of RC Beams Solved Problems Design of Continuous Beams Shear Design of Concrete Beams Torsion Design of RC Beams Serviceability Limit States I: Deflection Calculations Serviceability Limit States II: Crack Control Shear Friction Design Design of Short Cantilevers Design of Deep Beams Problems on RC Beam Design CHAPTER 3: Design of Reinforced Concrete Slabs Design of RC Solid Slab and Beam System RC Solid Slab Design Solved Problems RC Paneled Beam System RC Paneled Beams Solved Problems Design of Hollow Block Slab Systems Hollow Block Slabs: Commentary for Students Solved Problems on Hollow Block Slabs Design of RC Flat Plate and Flat Slab Systems Solved Problems on RC Flat Slabs Design of RC Stairs RC Stairs Reinforcement Details and Solved Problems Sample Exam Problems on RC Stairs Sample Exam Problems and Ideas on Floor Slabs Summary Notes on RC Slab Design and Exam Problems Unsolved Practice Problems on RC Slabs CHAPTER 4: Design of Reinforced Concrete Columns RC Column Design Column Design Example Column Design Summary and Commentary for Students Eccentric Section Design Eccentric Section Commentary for Students RC Columns Design Tips RC Columns Problems CHAPTER 5: Foundation Design Design of Isolated Footings Solved Problems on Isolated Footing Design CHAPTER 6: Design of Reinforced Concrete Frames Reinforced Concrete Frames Design Reinforced Concrete Frames Solved Problems and Exams Sample Practice Problems CHAPTER 7: Design of Reinforced Concrete Halls Design of RC Halls: North Light Roof Systems Commentary for Students on RC Hall Design CHAPTER 8: Design of Concrete Tanks and Water Structures Crack Control of Concrete Structures Solved Problems on RC Crack Control Design of Rectangular RC Tanks Design of Circular RC Tanks Design of RC Tanks Rested on Soil Solved Problems on RC Tank Design Practice Problems CHAPTER 9: Design of RC Buildings for Lateral Loads Design for Lateral Loads CHAPTER 10: Design of Prestressed Concrete Structures Prestressed Concrete Design Prestressed Concrete Losses Prestressed Concrete Anchorage CHAPTER 11: Design of Repair and Retrofit of RC Structures Cracks in RC Structures Concrete Structures Assessment Tests Repair and Retrofit of Concrete Slabs Repair and Retrofit of Concrete Beams Repair and Retrofit of Concrete Columns أهدي هذا العمل الي أحبائي طلاب الهندسة المدنية والانشائية والمعمارية وهندسة التشييد وزملائي المهندسين و كذلك أساتذة الهندسة الانشائية بالجامعات. أسأل الله أن ينفع به ويجعله خالصا لوجهه. ولا تبخلوا في الدعاء لي ان وجدتم فائدة في هذا الكتاب. الكتاب يشمل جميع موضوعات تصميم الخرسانة المسلحة بطريقة ميسطة بدءا من الأحمال والنظم الانشائية حتي الأساسات وتدعيم المنشات في أكثر من 2000 صفحة. لقد شغلتني منذ فترة طويلة فكرة تـأليف كتاب دراسي احترافي في تصميم المنشآت الخرسانية بطريقة مبسطة، ولكنها محكمة من الناحية الفنية، مما يجعل المادة في متناول معظم طلاب الهندسة المدنية، حتى أولئك الذين لا ينوون التخصص في الهندسة الإنشائية. كنت أنوي أن يعكس الكتاب خبرتي في الهندسة الإنشائية، وتحديدًا تصميم الخرسانة الإنشائية، والتي تمتد لأكثر من 20 عامًا من الممارسة المهنية والبحث والتدريس. ومن هذا المنطلق، قمت على مر السنين بتأليف وتطوير مجموعتين من المحاضرات في تصميم الخرسانة المسلحة، استخدمتهما لتدريس الطلاب في جامعات الشرق الأوسط وأمريكا على مدار تاريخي الأكاديمي منذ درجة مساعد تدريس حتى أستاذ مشارك في الهندسة الإنشائية. يهدف هذا "الكتاب" إلى تقديم مساهمة متواضعة في مجال التصميم الإنشائي للخرسانة المسلحة لجعله أكثر سهولة وتناولا وفائدة للطلاب الجامعيين والمهندسين الإنشائيين. والكتاب يمثل مجموعة محاضراتي في التصميم الخرساني ، والتي طورتها على مدار ثمان سنوات. معظم المادة المقدمة، وخاصة فيما يتعلق بالأنظمة الإنشائية والتحليل، يمكن أن تكون مفيدة في التصميم الخرساني باستخدام أي كود بناء، مع التعديلات المناسبة حسب الكود المحلي، حيث أن الأساس النظري المستخدم مشترك في العديد من الجوانب بين مختلف الأكواد المعتمدة. وقد كنت أنوي الانتظار حتى أعيد كتابة هذه المحاضرات وأحدثها، مع إثرائها بمناقشات ومواد توضيحية إضافية، في نسق كتاب احترافي واختيار ناشر لتحرير ذلك الكتاب ونشره بشكل جذاب. ولكن هذا المشروع، ونظرًا لضخامة حجم المادة والتزاماتي الأكاديمية والمهنية الحالية، قد يستغرق بضع سنوات أخرى حتى يكتمل بالطريقة التي تصورتها. ولذلك فقد شعرت بالذنب لتأخير نشر هذا العلم حتى ييسر الله النشر الرسمي رغم أنه يمكن أن يساعد العديد من الطلاب والمهندسين حتى ذلك الحين، وبالتالي فإنني أقدم هذه المحاضرات كما هي بخط يدي ورسومي التوضيحية اليدوية في هذا "الكتاب"، مع نيتي مراجعتها وتحديثها ونشرها بشكل احترافي في المستقبل إن شاء الله. وقد ساعدت هذه المحاضرات على مدار السنوات آلافا من طلاب الهندسة المدنية والمهندسين الممارسين على تعلم تصميم الخرسانة الإنشائية بنجاح. يرجى العلم بأنني أحتفظ بحقوق نشر هذه المادة لغرض وحيد هو نشر الكتاب بطريقة أكثر رسمية في المستقبل؛ ومع ذلك، فأنا أمنح الحق لأي فرد في استخدام الكتاب للأغراض الأكاديمية والتعليمية أو لأغراض التصميم الاحترافي دون إذني. كما أمنح الحق لأي فرد في نشر هذه المادة كما هي على الإنترنت وتوزيعها كما هي إلكترونيًا أو مطبوعة. لكن القيد الوحيد على الاستخدام هو إعادة إنتاج المادة جزئيًا أو كليًا بتنسيق مختلف دون الاقتباس المناسب لاستخدامها لأغراض تجارية دون إذن. دكتور مهندس: وائل حسن أستاذ مشارك في الهندسة الإنشائية Book Sharing_2.pdf
    1 point
  6. Leave it to the default value (8 seconds). For your structure, any number more than 2 seconds will not change the design force. So this parameter is useless for your purposes.
    1 point
  7. BCP has not given this value. You can put reasonable number based on your engineering judgment. Majority of buildings do not fall in that part of response spectrum, so it does not matter ( Unless you are working on building more than 50 storey, or building with base isolation).
    1 point
  8. Dik

    CANOPY LOAD

    Then you likely have to do a preliminary design of the canopy to determine what shears and moments are created. In addition, you have to clearly stipulate what your design criteria is for the canopy designer and fabricator, so he ends up with similar. You also have to stipulate on your drawings what your design loads and resulting reactions (that includes +ve and -ve forces) and leave the final design with a condition that the canopy loads cannot exceed your loading criteriia, and that you are not responsible for any redesign costs. It's a bad way to do it. It's difficult in assigning someone the loading; I hope you have some control over it. Why would the regulatory authority have any input as to the type of construction. HSS columns with proper anchors is a much better way to go. If the column has to be concrete, it might be better to construct it once you have the canopy loading, and put the excess design into the foundations. Foundation costs are relatively insensitive to loading (usually). Dik
    1 point
  9. I'd likely try to develop two separate lateral load resisting elements in 'both halves' of the structure and isolate the connection at the top. How are the lateral loads resisted? What is the height? and what is the approximate height from floor to floor?
    1 point
  10. Can anyone guide the general principles to be considered for designing of Concrete Pad / Strip footing for Steel Columns? I would really appreciate if group can refer some relevant material or excel sheets.
    1 point
  11. Dear Waqar please follow ACI 224 "Control of Cracking in Concrete Structures". It can easily be downloaded and lucidly furnish guidelines. You may also consult Handbook of concrete engineering by Mark Fintel
    1 point
  12. Dear Imran sb, Thank You, very much, we are on it. Slab is octagonal and pouring is done 4 portions first and then a gap and 4 are poured, temp is monitored by embedded sensor and readings are okay, a canopy is set above the slab and heaters are placed to maintain the temperature difference normal, scanning results are received, 50 readings, top/bottom 25/25, 50 percent are crossing into the core area or below the top bar, mostly are top side cracks, crack depths are max 20cm, cover to top rebar is 8cm. one thing i observed that mix design recommends 3 days strength 60/90 but in actual testing it is 87/90 in 3 days, rate of hydration is more then recommended or observed during trial mixes, please some data/example to calculate crack widths. Thank You
    1 point
  13. Salam Zohair, it ok to have water tank there, just check any column loads which are around the periphery of tank and design walls of the tank for shear, take care to make its foundation joints and other top slab level joints are sealed, any leakage could create serious problems.
    1 point
  14. Dik

    UGWT Location within the Raft

    How far below grade is it founded? How thick is it? Can the UGWT be built into the raft foundation. Can it be expanded in size to minimise the depth and the loads on the tank walls?
    1 point
  15. Dik

    High strength Concrete

    I assume your mix design is 90 MPa concrete (@28 days). I don't know what the concrete object that has the cracking is. For that strength gain, there is likely a very small portion of fly-ash, so there is likely a lot of cement powder. What is the size of your aggregate; you could have a lot of shrinkage. 1.5% air is not unusual. You can have that amount with normal mixing. This is normally less than 1%. In our environs exterior concrete usually has about 6% or 7% for frost resistance. A lot of our concrete has fly-ash for economy. I've not used self compacting concrete, but have often spec'd superplasticisers. I always spec mechanical vibration, even for piles and caissons. Dik
    1 point
  16. Please leave it to some one who understands it better. After reading your post, I think, you are not the right person ( from practical building construction point of view) to get the advice.
    1 point
  17. Study the PMM diagram. For column at top floor, small axial load coupled with relatively large moment is causing your PMM ratio to shoot up.
    1 point
  18. Design column moments after P-delta analysis are exceeding the code limit of 1.4 times the moments due to 1st degree analysis. Check any member by manual calculations to make sure that the change in member ( column, beams, or both) size is required. In addition, you can do following: ETABS uses a default value of 1 for effective length factors; you should revise the factor if you have stiffer beams. you can also review moment coefficient factor. make sure that unbraced length ratios are correct.
    1 point
  19. Salam, In reviewing one etabs model, I found that my retaining wall was assigned membrane, when removed and replaced with shell this negative time period problem resolved. Thank you
    1 point
  20. well explain by Baz but i want add to it 1.) Load Patterns refer to the types of load which will be used like Dead, Super Dead ,Live , Earth Quack etc. 2.) Load Cases refer to the Analysis 3.) Load Combinations refers to Design
    1 point
  21. Moment release in SAFE doesn't work regardless the model. probably a bug in the program. checked it with another model and lap top. Thanks by the way
    1 point
  22. Hi Groszni, There are a number of ways in which it can be done depending upon what kind of forces need to be transferred. 1) For Pinned End Beams The primary force to transfer is shear. You can embed a steel plate in concrete column with anchor studs (industry practise is to use Nelson Studs D2L or D3L Mild Steel Studs). The beam would get welded on the face of embeded plate. In that manner you can transfer the desired force in concrete. To develop concrete for applied shear force you would need to use equations outlined in ACI Code Appendix D. 2) For Moment and Shear Transfer For this case, you need to transfer tension compression force couple as well as shear. The best thing to do would be either to weld rebars as shown below or provide anchor bolts where high capacities are required. Shear shall be transferred by studs. Use ACI Appendix D for required equations. Figure one is shown for presentation purpose only. A web connected beam won't be transferring any moment in the column. Hope that helps. Thanks. Figure 1: Figure 2
    1 point
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