Posted By Ken Urquhart
Chandra,

This is going to be a fairly lengthy response, but I consider in the circumstances and in the light of the limited information that you give, that it is necessary to respond on this scale.

Having said that and not wishing to absolve myself for my comments or guidance, I would say that the information is not prioritised and is certainly not exhaustive.
I hope however that you find some of the content answers your posting and is useful o you, and indeed to others who hopefully review even if they dont add to or comment on other peoples postings.

I gather from your e-mail address that you are in the Gulf, perhaps the UAE.

What storms do you get there?

My understanding is that in the period May to October it is hot, dry, humid in parts with little or no wind, and, in the late October through to April period it is your cool season, probably very pleasant to Europeans, cold to you, and in this cooler period you do get occassional wind storms.

Do you also get Cyclone type storms.
I quickly looked at a UAE web site but could not come up with a Weather forecasting facility local to your area, perhaps I was looking under the wrong heading.

Anyway, my experience of weather is currently of Hong Kong, and Asia Pacific.

In the rainy season May to October we get Rain storms, Amber, Red and Black rain.
(This can mean anything from 50 to 300 to 400mm of rain in a period of between one hour up to maybe 6 hours, an awful lot of water).

Also Tropical Depressions, Tropical Storms, Typhoons and occassionally Super Typhoons.
(These of course bring much more severe conditions from gentle rain to raging torrents of water, thunder and lightning and winds of anything from 45kph to in excess of 150kph, and/ or any combination of all of these conditions all of which can develop and run over 1 to as much as 5 days at a time - intensity building, peaking and then reducing and return to normal weather).

Consequently we as the client, the Construction industry in general and the Contractors have to prepare within there "Project specific Safety Plans" Severe Weather and Typhoon procedures.

All of us have to allocate Teams who go on standby dependant upon what the weather condition is or is likely to be.

We get forecasts from the Hong Kong Observatory, supplemented by the US Navy's Pearl Harbour Pacific Weather Typhoon and Storm monitoring centre, plus some other local Weather information sources, and the UK Met office. (No Seaweed hanging by the door here I'm afraid)

The following web sites will be of interest.

www.weather.gov.hk/contente.htm

www.npmoc.navy.mil/jtwc.html

www.metoffice.gov.uk/

The Hong Kong Observatory gives useful guidance for Construction and related industry projects as to precautions to take in times of severe weather and typhoons.

Look on there web site, under Tropical Cyclones, you will find various information including basic checklists for construction industry action in times of Cyclones/Typhoons.

Similarly the HK Government, The HK Construction Industry Trade Associations and the HK Institution of Engineers and other Construction Industry Professional bodies also issue guidance.

Some other HK web sites that might be of help;

www.info.gov.hk/labour/eng/news/index.htm
Look here in this page for the Booklet of action to be taken in times of Typhoons and rainstorms, about 3 entries down the page.

www.etwb.gov.hk/content/index.htm
On this site look at the Publications section of the "Works Bureau."

www.info.gov.hk/ced/
This is the site of the Civil Engineering Department.

The requirement in simplistic terms is to recognise that in and at Design stage,that weather is factored in.
Also in this region Earthquake aspects are designed in.

As for check lists and your problem of failure of a structure, possibly under or including overloading, if I understand your posting correctly, I think that you are raising two distinct issues.

1). The effects of weather on a partly erected/completed structure, its permanent works and related temporary works.

There should be Engineering Design checklists for the structure and guidelines as to how the fabrication, erection, tempoary guying, bracing, propping etc is to be addressed, all provided by the Engineering and Design/Architectural disciplines in your client/consultant and your own Teams.

These apects must be incorporated in the Safety Risk Assessment and the resultant Safety Method Statemet for the process.

For aspects that you do not understand or do not have the Technical knowledge of or for, you must involve members of your Team who are Engineers or have engineering and design competences.

Regardless of Weather conditions the temporary and part complete permanent works must be safeguarded by designed and managed Bracing, Guying, Tying and properly constructed Temporary Works.
eg: Scaffolding; Falsework; Shoring; Guying and Bracing, Props and lines - all dependant upon what the structure is.

The overloading risk is ever present, when, during the Construction phase, components and materials either for temporary works, or to be constructed in as part of the permanent works are loaded in bundles or packs in one common and single spot or loaction on a part structure.

This can impose loads that the structure was never designed to cater for, and cause collapse or failure with all the ensuing injury, damage, loss, wastage etc.,

2). Add to the above the factors of "Severe Weather" or anticipated stormier than usual weather and, if appropriate precautions have not ben taken, you then have a potential disaster faqcing you.

In the "Severe Weather" times and areas of the world where such conditions are previlant the Designs must include as must the Risk Assessments and the Safety Method Statements, the check lists and methodology criteria to mitigate as much as possible the oncoming conditions.

Sometimes in approaching "Severe Weather Conditions" you get time to take significant protection measures.
At other times the storms can come at you at surprisingly unexpected speed, particularly for example where a previously tracked storm is discounted because its path or course is veering away from your area;

Suddenly, and without much warning the storm changes course, absorbs more energy, picks up speed and is on you before you have much time to "Get Ready" .

Another factor in these conditions is that despite the designed evacuation arrangements;
Plans and proceedures that you may have diligently developed, trained people in and implemented, the locals natural instinct of self preservation coupled with a "It's a day or a couple of days unexpected holiday,(They don't think about the real danger) and they all rush off as soon as they even get a sniff of the official Warning signal being issued by the authorities before it is actually issued.

When this happens and your preparedness plans have not been put fully into action by those who have a contribution to make, you will have problems if the storm hits or is of high intensity.

Some aspects of the Check Lists that you MUST build in - You can review your own situation and the web sites that I have given you and develop your own list/system further.

Check Lists start with Trained People.

Then establish a Severe Weather standby Emergency team.
Ensure that your Contractors if you are the client have also all selected, trained and appointed Emergency teams.

These people may be required to remain at a safe sheltered place at the worksite for the duration of the storm to deal with conditions as and when they arise, subject to Risk Assessment and the conditions not endangering them - otherwise let nature take its course and your emergency team stay in the shelter.

They will need provisions, food, clean drinking water, PPE and foul weather clothing.
They will also require Radios, Telephones, Flashlights etc etc.

If and when any of the Team go out to monitor or deal with a storm condition or effect they must go in a minimum number according to the risk so that if any get into difficulties, others can help effect rescue or return for help.

As an absolute minimum, Team Members should never go out in less than 2 persons at a time.
They must have means of monitoring the storm during there on duty phase as the Emergency Team.
They must have means of maintaing voice contact with each other at all times and with colleagues in the shelter.

On the site:
All Temporary Buildings must be designed for Severe Weather conditions/Storms and be anchored, guyed/tied and braced accordingly.

Storage containers must be similarly guyed, tied, braced and weighted down as they can fly in the wind like Paper aeroplanes.

Materials, equipment and components must be sensibly stored so that they can be secured, lashed, or weighted down, or better still not brought to site till absolutely necessary for inclusion in the works.

Plant especially Cranes and Tower cranes must be designed for Typhoon conditions and out of service conditions in times of Typhoon.
Jib cranes must have there Jibs/Booms lowered to horizontal.
Vehicles and Plant should be parked up tightly alongsidde each other in small compound areas.
Vessels, Boats/Ships MUST go to Typhoon shelters.

People must be kept away from shorelines and high ground or high stgructures where gusts of wind could pick them up and sweep them away even over the tops of guard rails and safety barriers.
If people have to go to exposed conditions they must be secured by solidly tied/anchored and tested/calibrated lifelines and safety harnesses.

Arrangements for storm water build up, drainage and run off must be made, including for collection, temporary holding lagoons and pumping away.
All slopes, excavations and earthworks, spoil heaps and stock piles must be prepared for scouring and water wash off and possible landslip.

As I said at the beginging of this response these are just some of the key issues that you need to plan for and think about, there are and will be more and some will be specifically peculiar to your project and your geographic location.

As to other technical information look at the British Standards web site at:

bsonline@techindex.co.uk
Look at the BS Code of practice for Wind loading, (Sorry I dont have the ref. No. to hand).
BS5531 Code of Practice for Safety in erecting structural frames.
BS5975 Code of Practice for Falsework.

Try also the British Constructional Steelworks Associations Guidance notes:
Safer Erection of Steel-Framed Buildings.
Downloadable in PDF format from:-

www.steelconstruction.org

These are just a few of the Technical Codes that may help.

Hope this is of some interest and help.
If you have any more specific questions that you think that I might be able to help with in regard to your posting please e-mail me directly.

Regards.

Ken Urquhart