EngrUzair

Members
  • Content count

    368
  • Joined

  • Last visited

  • Days Won

    159

EngrUzair last won the day on April 29

EngrUzair had the most liked content!

7 Followers

About EngrUzair

  • Rank
    Major

Contact Methods

  • Yahoo
    engruzair@yahoo.com

Profile Information

  • Gender
    Male
  • Location
    Rawalpindi
  • University
    MSU USA & UET Taxila
  • Interests
    Structural loading, RC design, Steel design, Fire damaged structures, Structural evaluation & rehabilitation

Recent Profile Visitors

940 profile views
  1. Check the following link. May be it could help. http://www.sepakistan.com/topic/115-pile-design/?do=findComment&comment=860 Regards.
  2. Can you add the reference, from where above excerpt has been taken? It is always a good idea to indicate the reference, whenever an excerpt is quoted to explain some technical matter or concept (especially when it is taken from some book or code). This helps the reader to consult the original reference and study in more details, if required. Regards.
  3. For Seismic Design requirements, you may refer to AISC 341-10 specification, that can be downloaded from here for free. Seismic compactness requirement are given in Chapter D. In order to avoid above error, you will have to try ONLY those sections that are seismically compact according to AISC 341. To avoid this error, the slenderness ratio (l/r) of the steel sections to be used for concerned members must not exceed 60. You will most probably need to reduce spacing (or increase number) of column bracing for this purpose. Regards.
  4. 1. Section 1.3.1 of AASHTO's Guide Specifications for Design of Pedestrian Bridges, 1997, states the following regarding the deflections:- "Members should be designed so that the deflection due to the service pedestrian live load does not exceed 1/500 of the length of the span. The deflection of cantilever arms due to service pedestrian live load should be limited to 1/300 of the cantilever arm. The horizontal deflection due to lateral wind load shall not exceed 1/500 of the length of the span." On the other hand, Section 5 of AASHTO's LRFD Guide Specifications for Design of Pedestrian Bridges, 2009, describes the following regarding the deflections:- "Deflections should be investigated at the service limit state using load combination Service I in Table 3.4.1-1 of AASHTO LRFD. For spans other than cantilever arms, the deflection of the bridge due to the unfactored pedestrian live loading shall not exceed 1/360 of the span length. Deflection in cantilever arms due to the pedestrian live loading shall not exceed 1/220 of the cantilever length. Horizontal deflections under unfactored wind loading shall not exceed 1/360 of the span length." 2. AFAIK ETABS 2016 can design steel connections. However, SAP2000 does not have this option. Regards.
  5. Yes. It is possible. But you must make sure, either by confirming from the architectural drawings, or the designer. Because the software model must conform to actual loading requirements, as indicated in architectural plans & relevant loading code. No. Floor Load is a specific command, indicating two-way load distribution. For one-way load distribution, STAAD uses ONEWAY command. Self weight of members defined under MEMBER PROPERTY command is automatically calculated by the software, when SELFWEIGHT command is used (as shown in second line of the following quote). Hopefully, it should be clear now. Regards.
  6. Here are my thoughts on the topic under discussion:- 1. The idea of re-categorizing the posts appears to be attractive. However, following points must be kept in mind in this connection: a. IMHO qualitative ranking of questions will certainly be a challenge to deal with. Firstly, because unfortunately even engineering education in our country is not upto the desired standard (as compared to that in advanced countries). Our students do get very good grades during studies, but their level of understanding & practical knowledge regarding engineering matters is not that good. Accordingly, many engineering concepts that are basic internationally, are not that easy to understand for our young engineers. Secondly, a piece of knowledge, no matter how basic or simple, will be difficult for me, in case I have not read about that earlier or have not been exposed to somehow during my field practice. Similarly, any engineering knowledge, no matter how much advanced or complicated, will be a piece of cake for me, if I already have know or have exposure to it. b. In case, we are determined to accept the challenge, than we will have to develop basic FAQ to a greater depth and to the most basic level, keeping in view general level of perception of our own engineers. 2. Assigning various forums to different moderators might not be beneficial for the forum or the members, as it might result in delayed replies to the queries, in case the concerned moderator is unable to see or reply the question, because of other commitments / unavoidable circumstances. 3. In addition, it would also a very good idea to add professional type sample Design Calculations in the forum (based on our own professional knowledge and experience) for various kind of civil engineering structures. This would certainly be helpful in developing professional sense in the engineering output of our young and fresh engineers. In the end, the idea of ranking the questions, addition of new sub-forums & improving the quality level of forum is appreciated and supported. Regards.
  7. 1. Above is an extract from your attached STAAD Input file. The last two lines indicate that two different uniform dead load values have been applied to the same floor area (ranging from 0 to 20 ft in X direction and 0 to 30 ft in Z direction), which is illogical & most probably indicated by mistake. In actual situation, these two load values will be for two different floor areas, for which at least one of the XRANGE & ZRANGE values must be different. 2. Here are two different sample situations for elaborating correct application of given dead loads: Situation A. 50 psf dead load for XRANGE from 0 to 10 ft and whole ZRANGE from 0 to 30 ft 122 psf dead load for XRANGE from 10 to 20 ft and whole ZRANGE from 0 to 30 ft STAAD commands for this situation are as under: YRANGE -10 0 ONE -50 XRANGE 0 10 ZRANGE 0 30 GY YRANGE -10 0 ONE -122 XRANGE 10 20 ZRANGE 0 30 GY Situation B. 50 psf dead load for whole XRANGE from 0 to 20 ft, but ZRANGE from 0 to 20 ft only 122 psf dead load for whole XRANGE from 0 to 20 ft, but for remaining ZRANGE from 20 to 30 ft STAAD commands for this situation are as under: YRANGE -10 0 ONE -50 XRANGE 0 20 ZRANGE 0 10 GY YRANGE -10 0 ONE -122 XRANGE 0 20 ZRANGE 20 30 GY 3. Now, what should be the actual values of XRANGE & YRANGE in your case? This will be clear from the floor details, as given in architectural drawings. You may ask the original designer to explain how he/she arrived at the floor load values (and even the other loads & design parameters) used in the STAAD model, if you are still unable to understand their basis. HTH Regards.
  8. Please check the following link for clarification:- https://wiki.csiamerica.com/display/etabs/Auto+vs.+Manual+meshing Regards.
  9. Floor loads may consist of several layers (slab itself, floor finish, ceiling plaster, weight of sand for sunken portion of slab to accommodate bath/kitchen piping to be laid under normal floor, etc). These may have different load types (e.g., dead or live) as well. Moreover, it is practically possible that two adjacent portions of a floor slab have different load values. For example, if one portion of a slab is to be made thicker for creating a raised platform, dead load being carried by thicker slab portion will be higher and different from the one having normal / lower thickness. All structural software (ETABS, SAP2000, etc.) have capabilities of applying above mentioned loads, through their basic commands & menu options. As such, STAAD surely has this capability too. I have used STAAD in the past. As such, if you could attach text input file of your model, I might be able to help clear your doubts. Regards.
  10. I have rechecked. The link is working. However, you may use the following link to download brochure of the seminar:- Brochure-A4-TallBuildings_PK-15-3-2017-2.pdf Regards.
  11. AA. NUST is also holding a similar but 2-days long Seminar and Workshop on 24th & 25th April 2017. Details are available at following link:- Nust-Tall Buildings Seminar April 2017
  12. General design procedure for design of a minaret, in accordance with UBC 1997, is available in the following document: Design of minaret.pdf Regards.
  13. AA! Dear Engineers, 1. What is the design life of an RC structure according to various international codes? Please refer to specific section of the code, if possible. 2.. What about design life of RC structures, being designed & constructed as per present practice in Pakistan? Is it mentioned somewhere? In it is not specified, then whether it should be same as recommended in international codes, or.........? Please discuss & give your recommendations as well. Regards.
  14. Dear Umar! Can you refer to the specific sections of different building codes, along with Design Life indicated therein? Regards.
  15. What was the cause of the problem? Please share for the information of others. Regards.