Regarding the news reports yesterday that the investigation report will be made public soon, I would like to offer some of my views on what could have happened. Take note that these are all speculation and that I have no knowledge of what is contained in that report.
There are many factors that can contribute to a failure during the demolition process. These are:
1. Lacking in procedures and guidelines to carry out a safe demolition job.
2. Risk Assessment not completed before and during the demolition phase.
3. Site operatives not following laid down method statements on the sequence of work and procedures.
4. Inadequate temporary supports to the structure or the elements of the structure being demolished. Temporary support should be provided for any or combination of the following conditions:
a. When the whole or any part of the structure is subjected to excess loading derived from the demolition activities, movement of powered mechanical plants or debris accumulation. Overloading in term of impact of falling large debris and accumulated debris on the floor may cause the floor to give way and result in chain reaction effect to the lower floor. Extra loading from the machinery used on top of the building should also be considered to prevent excessive loading.
b. When any part of the structure or any element being demolished is not self-supporting; or
c. When the temporary stability of the structure or its elements could be impaired as a result of the demolition activities.
5. In case of prestessed concrete structure (constructed of either precast or cast-in-place concrete in which prestressing is introduced to the concrete by tensioning the steel reinforcement, or tendon, to counteract a desired degree of stress resulting from a given external loading – Hong Kong Code of Practice for Demolition) any accidental and unplanned cutting of tendons may cause the elements of building structure (Beams or Slabs) to rapture and become unstable. The prestressed concrete floor system shall be properly shored prior to detensioning to prevent the collapse of the system. The release of energy during the demolition of prestressed concrete could be extremely hazardous.
6. Lack of site supervision and inspection during the demolition job.
These are some of the general factors that can cause failure during demolition works. I am in no way referring to any specific cases here!
9/18/09
'Something went wrong'
I saw in the papers yesterday that Datuk Seri Kong Cho Ha said the investigation report will soon be made public. He also mentioned to the media that 'something went wrong'. Well I'll be looking forward to know what it is that went wrong! I guess with Raya around the corner and the PKFZ and cowhead issue, the Jaya issue got left behind a bit...but I'm also sure the authorities are doing what they can under the circumstances.
The reporting was pretty uneven. I observed a few discrepancies etween the reports in the media. Ok, so I cannot read Chinese, so I can't say what's on there. Firstly, I noticed that none of the English papers named the agencies involved in compiling the investigation report. But the Malay papers did. But, the Malay papers also got the agencies mixed up. According to Utusan, these are the agencies: Ikram, Dosh, JKR, MPPJ (notice the wrong acronym!!), IEM and LAM. According to Harian Metro, the agencies are CIDB, MBPJ, JKR, IEM, LAM, Bomba and PDRM.
So which are the actual agencies? Safe to say MBPJ, JKR, IEM and LAM were involved. They should be anyhow. But I seriously think Ikram and Dosh were also part of the report commitee, with Bomba and PDRM. Not sure about CIDB, though.
The Malay paper Utusan also worngly stated that the number of deaths in the collapse was 4 Indonesians. In actuality 7 Indonesian workers died.
One of the papers (dont recall which) also named one of the firms: DP Architects. From earlier reporting several months ago, there were 7 firms blacklisted. So why only this one was mentioned? As the architect, I imagine they were the submitting authority, so maybe thats why.
All in all, it appears to me that the press ambushed the minister when he exited the cabinet meeting, and in the haste to answer reporter's questions, and they're haste to take it all down, there was some misinfo communicated. I doubt they held a press conference otherwise sure there won't be these kinds of mistakes. Can any PR person advise me on that?
The reporting was pretty uneven. I observed a few discrepancies etween the reports in the media. Ok, so I cannot read Chinese, so I can't say what's on there. Firstly, I noticed that none of the English papers named the agencies involved in compiling the investigation report. But the Malay papers did. But, the Malay papers also got the agencies mixed up. According to Utusan, these are the agencies: Ikram, Dosh, JKR, MPPJ (notice the wrong acronym!!), IEM and LAM. According to Harian Metro, the agencies are CIDB, MBPJ, JKR, IEM, LAM, Bomba and PDRM.
So which are the actual agencies? Safe to say MBPJ, JKR, IEM and LAM were involved. They should be anyhow. But I seriously think Ikram and Dosh were also part of the report commitee, with Bomba and PDRM. Not sure about CIDB, though.
The Malay paper Utusan also worngly stated that the number of deaths in the collapse was 4 Indonesians. In actuality 7 Indonesian workers died.
One of the papers (dont recall which) also named one of the firms: DP Architects. From earlier reporting several months ago, there were 7 firms blacklisted. So why only this one was mentioned? As the architect, I imagine they were the submitting authority, so maybe thats why.
All in all, it appears to me that the press ambushed the minister when he exited the cabinet meeting, and in the haste to answer reporter's questions, and they're haste to take it all down, there was some misinfo communicated. I doubt they held a press conference otherwise sure there won't be these kinds of mistakes. Can any PR person advise me on that?
9/9/09
A - Z of demolition
Here is an article I wrote on demolition safety. Just thought I'd post it here as it is relevant to the theme of this blog:
According to OSHA (the Occupational Safety and Health Administration) of the US Department of Labor demolition work is a highly-specialised area of practice in the construction industry and the highest standards of safety should be observed.
OSHA’s Fact Sheet on Demolition and cleanup states:
“Before starting a demolition, the person or persons in charge must adequately prepare for the task with regard to the health and safety of the workers. These preparatory operations involve the overall planning of the demolition job, including the methods to be used to bring the structure down, the equipment necessary to do the job, and the measures to be taken to perform the work safely.
“Before doing any demolition work, inspect available Personal Protective Equipment (PPE), and select, wear and use the PPE appropriate for the task.
“Demolition work involves many of the same hazards associated with construction work. However, demolition also poses additional hazards due to unknown factors such as: deviations from the structure’s original design, approved or unapproved modifications that altered the original design, materials hidden within structural members, and unknown strengths or weaknesses of damaged materials. To counter these unknowns, all personnel involved in a demolition project need to be fully aware of these types of hazards and the safety precautions available to control these hazards.”
Malaysia is rapidly industrializing and steps should be taken to review all Demolition Guidelines and make them available for all those involved in the construction industry – from regulators and standard-setters, to architects and engineers, project managers and contractors.
Without an agreed Code of Best Practice, the industry will continue to suffer mishaps and traumas, as witnessed in several accidents lately, including the collapse of the old Jaya Supermarket podium block in Section 14, Petaling Jaya. The site had been targeted for demolition prior to redevelopment work. More such projects will be undertaken from time to time, to ensure continuing urban redevelopment.
From this very informative website, and others, the following ABC of demolition best practices has been compiled as a starting point:
A: All roof cornices or other ornamental stonework should be removed before walls are pulled down.
B: Brace or shore up walls and floors of structures which have been damaged and which workers must enter.
C: Chemicals including hazardous gases, explosives or flammable materials which may have been used in any pipes or tanks within the property should be tested and purged.
D: Demolition of exterior walls and floors should begin at the top of the structure and proceed downwards always. Also, Debris Clearance procedures should be provided for.
E: Engineering surveys must be performed on each structure being considered for demolition prior to demolition, to check the condition of floors, walls etc and to assess the possibility of an unplanned collapse of any portion of the structure. This enables the demolition contraction the opportunity to evaluate the job scope.
Explosives should only be used to set off deliberate collapse. This type of demolition should only be undertaken by qualified persons or specialists such as blasters.
F: Flagging should be done periodically and flaggers (those that provide temporary traffic control) should wear high visibility fluorescent clothing. Additionally, a Fire Plan should also be in place outlining the evacuation procedures for workers on site in the event of a fire.
G: Guidelines should be in place for all forms of construction including demolition works. These guidelines shall cover inspections,
H: Hazards encountered when entering and working in confined spaces are capable of causing illness, injury and also death. Some examples of such spaces include storage tanks, vessels, pits vaults, casings and silos. Accidents occur because of failure to recognize the hazards of working in confined spaces which include danger of explosion, poisoning and asphyxiation.
I: Inspections – prior to demolishment, to ensure structural defects are noted, such as weak mortar joints, cracks and openings in brickwork etc. Also, continuing inspections are required as the work progresses to detect other hazards. Focused inspections are also needed which include walk-around inspections. Such inspections shall be comprehensive. Inventory handling is also needed to ensure there is a complete and detailed list of all materials used on the worksite.
J: Job training is required for all workers on a construction or demolition site – from the flaggers who manage the traffic to equipment operators and workers on foot.
K: Knowledge of safety procedures must be shared with workers, through regular and appropriate communications.
L: Lighting for workers should be appropriate for the task at hand. Where available lighting is insufficient, flares or chemical lighting can be used but glares affecting worker health should be limited.
M: Mechanical demolition works shall be such that no workers shall be permitted in any area when using demolition balls; this is to ensure workers safety is not compromised.
N: A National Emergency Response Plan is also needed, to ensure construction-related disasters are dealt with according to international guidelines.
O: Occupational Health & Safety of workers cannot be compromised. Under the OSH Act of the U.S., employers need to provide each of their employees an employment and place of employment which is free from recognized hazards that can cause harm or death.
P: Planning for demolition work is as important as actually doing the work. All planning should be done by a competent team experienced in demolition work. Additionally, all necessary Permits ought to be applied for and complied with.
Q: There are no quick or short cuts in the construction industry; preparation is vital.
R: Respiratory protection needs to be in place, to ensure worker safety. Risk planning is also important, to ensure preparedness in times of emergency.
S: Signs should be in place eg. Highway and road signs for information, to ensure pedestrians, residents and drivers are kept informed of the work in progress. Also, select appropriate PPE wear for the various tasks.
T: Traffic control plans are required for the movement of vehicles in areas where there are also workers performing other tasks. This includes an internal traffic control plan within the demolition or construction worksite and traffic control devices such as cones, barricades and hoardings.
U: Use enclosed chutes with gates on the discharge end to drop demolition material to the ground or into debris containers.
V: Vehicular safety – vehicles used for transporting explosives, blasting agents and blasting supplies should not be transported with other materials or cargo and there are other restrictions in place regarding handling of such cargo. Workers have also been struck by moving vehicles or mobile equipment
W: Walls should not be allowed to fall on the floors of a building in masses that would exceed the safe carrying capacities of the floors. Also, no wall sections one storey in height or higher, should be permitted to stand alone without bracing. Walls should be left in a stable condition at the end of each work shift.
X: Accidents do happen such as natural disasters, terrorist events, unplanned collapses, etc. The safety of all those who assist in disaster recovery should also be protected through proper procedures and guidelines.
Y: Why do accidents happen? By undertaking a risk assessment of each project or job, many workplace disasters can be avoided.
Z: Zone protection – e.g. use of various styles of concrete, water, sand, collapsible barriers, crash cushions etc are recommended to limit motorist or pedestrian intrusions into the construction work zone.
The above are only some of the key aspects to be considered when undertaking demolition work. A full review of all existing procedures ought to be undertaken by a select committee comprising all key stakeholders and professionals to ensure safe construction practices for future generations.
According to OSHA (the Occupational Safety and Health Administration) of the US Department of Labor demolition work is a highly-specialised area of practice in the construction industry and the highest standards of safety should be observed.
OSHA’s Fact Sheet on Demolition and cleanup states:
“Before starting a demolition, the person or persons in charge must adequately prepare for the task with regard to the health and safety of the workers. These preparatory operations involve the overall planning of the demolition job, including the methods to be used to bring the structure down, the equipment necessary to do the job, and the measures to be taken to perform the work safely.
“Before doing any demolition work, inspect available Personal Protective Equipment (PPE), and select, wear and use the PPE appropriate for the task.
“Demolition work involves many of the same hazards associated with construction work. However, demolition also poses additional hazards due to unknown factors such as: deviations from the structure’s original design, approved or unapproved modifications that altered the original design, materials hidden within structural members, and unknown strengths or weaknesses of damaged materials. To counter these unknowns, all personnel involved in a demolition project need to be fully aware of these types of hazards and the safety precautions available to control these hazards.”
Malaysia is rapidly industrializing and steps should be taken to review all Demolition Guidelines and make them available for all those involved in the construction industry – from regulators and standard-setters, to architects and engineers, project managers and contractors.
Without an agreed Code of Best Practice, the industry will continue to suffer mishaps and traumas, as witnessed in several accidents lately, including the collapse of the old Jaya Supermarket podium block in Section 14, Petaling Jaya. The site had been targeted for demolition prior to redevelopment work. More such projects will be undertaken from time to time, to ensure continuing urban redevelopment.
From this very informative website, and others, the following ABC of demolition best practices has been compiled as a starting point:
A: All roof cornices or other ornamental stonework should be removed before walls are pulled down.
B: Brace or shore up walls and floors of structures which have been damaged and which workers must enter.
C: Chemicals including hazardous gases, explosives or flammable materials which may have been used in any pipes or tanks within the property should be tested and purged.
D: Demolition of exterior walls and floors should begin at the top of the structure and proceed downwards always. Also, Debris Clearance procedures should be provided for.
E: Engineering surveys must be performed on each structure being considered for demolition prior to demolition, to check the condition of floors, walls etc and to assess the possibility of an unplanned collapse of any portion of the structure. This enables the demolition contraction the opportunity to evaluate the job scope.
Explosives should only be used to set off deliberate collapse. This type of demolition should only be undertaken by qualified persons or specialists such as blasters.
F: Flagging should be done periodically and flaggers (those that provide temporary traffic control) should wear high visibility fluorescent clothing. Additionally, a Fire Plan should also be in place outlining the evacuation procedures for workers on site in the event of a fire.
G: Guidelines should be in place for all forms of construction including demolition works. These guidelines shall cover inspections,
H: Hazards encountered when entering and working in confined spaces are capable of causing illness, injury and also death. Some examples of such spaces include storage tanks, vessels, pits vaults, casings and silos. Accidents occur because of failure to recognize the hazards of working in confined spaces which include danger of explosion, poisoning and asphyxiation.
I: Inspections – prior to demolishment, to ensure structural defects are noted, such as weak mortar joints, cracks and openings in brickwork etc. Also, continuing inspections are required as the work progresses to detect other hazards. Focused inspections are also needed which include walk-around inspections. Such inspections shall be comprehensive. Inventory handling is also needed to ensure there is a complete and detailed list of all materials used on the worksite.
J: Job training is required for all workers on a construction or demolition site – from the flaggers who manage the traffic to equipment operators and workers on foot.
K: Knowledge of safety procedures must be shared with workers, through regular and appropriate communications.
L: Lighting for workers should be appropriate for the task at hand. Where available lighting is insufficient, flares or chemical lighting can be used but glares affecting worker health should be limited.
M: Mechanical demolition works shall be such that no workers shall be permitted in any area when using demolition balls; this is to ensure workers safety is not compromised.
N: A National Emergency Response Plan is also needed, to ensure construction-related disasters are dealt with according to international guidelines.
O: Occupational Health & Safety of workers cannot be compromised. Under the OSH Act of the U.S., employers need to provide each of their employees an employment and place of employment which is free from recognized hazards that can cause harm or death.
P: Planning for demolition work is as important as actually doing the work. All planning should be done by a competent team experienced in demolition work. Additionally, all necessary Permits ought to be applied for and complied with.
Q: There are no quick or short cuts in the construction industry; preparation is vital.
R: Respiratory protection needs to be in place, to ensure worker safety. Risk planning is also important, to ensure preparedness in times of emergency.
S: Signs should be in place eg. Highway and road signs for information, to ensure pedestrians, residents and drivers are kept informed of the work in progress. Also, select appropriate PPE wear for the various tasks.
T: Traffic control plans are required for the movement of vehicles in areas where there are also workers performing other tasks. This includes an internal traffic control plan within the demolition or construction worksite and traffic control devices such as cones, barricades and hoardings.
U: Use enclosed chutes with gates on the discharge end to drop demolition material to the ground or into debris containers.
V: Vehicular safety – vehicles used for transporting explosives, blasting agents and blasting supplies should not be transported with other materials or cargo and there are other restrictions in place regarding handling of such cargo. Workers have also been struck by moving vehicles or mobile equipment
W: Walls should not be allowed to fall on the floors of a building in masses that would exceed the safe carrying capacities of the floors. Also, no wall sections one storey in height or higher, should be permitted to stand alone without bracing. Walls should be left in a stable condition at the end of each work shift.
X: Accidents do happen such as natural disasters, terrorist events, unplanned collapses, etc. The safety of all those who assist in disaster recovery should also be protected through proper procedures and guidelines.
Y: Why do accidents happen? By undertaking a risk assessment of each project or job, many workplace disasters can be avoided.
Z: Zone protection – e.g. use of various styles of concrete, water, sand, collapsible barriers, crash cushions etc are recommended to limit motorist or pedestrian intrusions into the construction work zone.
The above are only some of the key aspects to be considered when undertaking demolition work. A full review of all existing procedures ought to be undertaken by a select committee comprising all key stakeholders and professionals to ensure safe construction practices for future generations.
8/27/09
what's going on!
Hey, whats going on with the Jaya site? I don't see ANY progress at all! I hope that the people doing the investigations are working on it...sure, these things take time, but there must be some outcome from this.
8/7/09
Demolition best practices in M'sia - long post!
I recently spoke to a demolition academic here in M'sia. I wont name him just yet but my mystery man has been active lately, and has even been featured in the papers! if you've been paying attention you will know who he is.
anyway I asked him a few Q's on demolition in M'sia. He is equally concerned as I am at the standard of demolition in this country. We are very good at erecting buildings but lacking when it comes to taking them down; this has a lot to do with the fact that urban developments in M'sia is still at the 'initial build' stage, uinlike say Hong Kong where they have gone into the 'redevelopment' phase. They need to tear down old buildings to make way for new developments - we havent reach that stage just yet.
Anyway, my mystery man had this to say (verbatim):
For demolition works conducted and awarded by means of public tender, normally the owner / developer will engage a consultant to carry out the tender process. In this tender process the contractors will have to submit a simplified Method of Statement and Work Program. The Contractor will be called upon to submit a detailed version if shortlisted or invited for a tender interview. In practice the demolition contractor take their own initiatives to prepare the method statement to perform the safest demolition job in their perspective. This method statement with several others information i.e. (Letter of Award for demolition work by Owner or Main Contractor, Location Plan, Photos of the building to be demolished, Insurance coverage and third party liabilities, location of dump site and approval), then submitted to local authority for them to issue a letter (allowing demolition works to be carried out) saying that they do not have any obstacle/impediment for the contractor to carry out the work. For the demolition work which exceeding 6 weeks or 20 Million Ringgit, the demolition contractor’s safety officer (Green Book Holder) have to fill up the JKJ 103 form (for registering the demolition site) and submit it to the Department of Safety and Health (DOSH). DOSH then will issue another letter (allowing demolition works to be carried out) saying that they do not have any obstacle/impediment for the contractor to carry out the work.
From my understanding and discussion with the demolition practitioners in Malaysia, there were several issues to be highlighted based on the demolition practice in Malaysia:-
1. There was lack of proper procedures or guideline on how to conduct a safe demolition job in Malaysia. For instance, there is no written procedures or guideline that require the demolition contractor to prepare a method statement. Otherwise in other country, to ensure a safe demolition job, they have a proper guidelines to refer, for examples:-
a. Code of Practice for Demolition, British Standard Institute (BSI). BS 6187: 1982;
b. Code of Practice for Demolition, British Standard Institute (BSI). BS 6187: 2000;
c. Building Department Hong Kong (1998), Code of Practice for Demolition of Buildings, Building Department Hong Kong;
d. AS 2601: 2000 (2000), The Demolition of Structures, Standards Australia International;
e. Department of Labour New Zealand (1994), Approved Code of Practice for Demolition, Department of Labour New Zealand; and
f. Demolition Safety Manual (National Demolition Association US)
2. At this time of writing, there isn’t a local governing body that regulates and reviews the demolition Method Statement, however there are some consultants engaged by the Owner / Developers or the Owner’s in-house Engineers does review and follow-up on the actual demolition work to be executed. Otherwise, in other country such as UK, US, Australia, and Hong Kong there is a guideline saying that the client or the demolition contractor need to appoint a demolition consultant who is technically capable to analyze or prepare a method statement in term of the techniques to be used, demolition sequence, risk assessment and safety aspects.
3. The local authorities may be lacking the dedicated department in the related field at this time to regulate the demolition methods submitted by the Demolition Contractors.
4. Most of the contract title for a new development project will be i.e. “Kerja-Kerja Meroboh dan Membina …” or “Demolition and Construction “ in one contract. The main contractor who received the job has to engage a specialist demolition contractor as their sub contractor to do the demolition work. This might affect the budget given to the sub contractor in term of safety aspects and time to do the job. In addition, most of the time the Main Contractor did not engage a demolition contractor to submit their methods and cost instead ‘suggested prices’ were submitted in the tender stage along with the building tender thus impairing the available budget to carry out a proper and safe demolition. Furthermore, some Main Contractors / Owners will specify a high SALVAGE VALUE in ‘salvage cum demolition’ related projects to set off their own operation cost. In these instances, the HIGHEST SALVAGE VALUE gets the demolition project and not the demolition contractor’s track record or safety standards.
anyway I asked him a few Q's on demolition in M'sia. He is equally concerned as I am at the standard of demolition in this country. We are very good at erecting buildings but lacking when it comes to taking them down; this has a lot to do with the fact that urban developments in M'sia is still at the 'initial build' stage, uinlike say Hong Kong where they have gone into the 'redevelopment' phase. They need to tear down old buildings to make way for new developments - we havent reach that stage just yet.
Anyway, my mystery man had this to say (verbatim):
For demolition works conducted and awarded by means of public tender, normally the owner / developer will engage a consultant to carry out the tender process. In this tender process the contractors will have to submit a simplified Method of Statement and Work Program. The Contractor will be called upon to submit a detailed version if shortlisted or invited for a tender interview. In practice the demolition contractor take their own initiatives to prepare the method statement to perform the safest demolition job in their perspective. This method statement with several others information i.e. (Letter of Award for demolition work by Owner or Main Contractor, Location Plan, Photos of the building to be demolished, Insurance coverage and third party liabilities, location of dump site and approval), then submitted to local authority for them to issue a letter (allowing demolition works to be carried out) saying that they do not have any obstacle/impediment for the contractor to carry out the work. For the demolition work which exceeding 6 weeks or 20 Million Ringgit, the demolition contractor’s safety officer (Green Book Holder) have to fill up the JKJ 103 form (for registering the demolition site) and submit it to the Department of Safety and Health (DOSH). DOSH then will issue another letter (allowing demolition works to be carried out) saying that they do not have any obstacle/impediment for the contractor to carry out the work.
From my understanding and discussion with the demolition practitioners in Malaysia, there were several issues to be highlighted based on the demolition practice in Malaysia:-
1. There was lack of proper procedures or guideline on how to conduct a safe demolition job in Malaysia. For instance, there is no written procedures or guideline that require the demolition contractor to prepare a method statement. Otherwise in other country, to ensure a safe demolition job, they have a proper guidelines to refer, for examples:-
a. Code of Practice for Demolition, British Standard Institute (BSI). BS 6187: 1982;
b. Code of Practice for Demolition, British Standard Institute (BSI). BS 6187: 2000;
c. Building Department Hong Kong (1998), Code of Practice for Demolition of Buildings, Building Department Hong Kong;
d. AS 2601: 2000 (2000), The Demolition of Structures, Standards Australia International;
e. Department of Labour New Zealand (1994), Approved Code of Practice for Demolition, Department of Labour New Zealand; and
f. Demolition Safety Manual (National Demolition Association US)
2. At this time of writing, there isn’t a local governing body that regulates and reviews the demolition Method Statement, however there are some consultants engaged by the Owner / Developers or the Owner’s in-house Engineers does review and follow-up on the actual demolition work to be executed. Otherwise, in other country such as UK, US, Australia, and Hong Kong there is a guideline saying that the client or the demolition contractor need to appoint a demolition consultant who is technically capable to analyze or prepare a method statement in term of the techniques to be used, demolition sequence, risk assessment and safety aspects.
3. The local authorities may be lacking the dedicated department in the related field at this time to regulate the demolition methods submitted by the Demolition Contractors.
4. Most of the contract title for a new development project will be i.e. “Kerja-Kerja Meroboh dan Membina …” or “Demolition and Construction “ in one contract. The main contractor who received the job has to engage a specialist demolition contractor as their sub contractor to do the demolition work. This might affect the budget given to the sub contractor in term of safety aspects and time to do the job. In addition, most of the time the Main Contractor did not engage a demolition contractor to submit their methods and cost instead ‘suggested prices’ were submitted in the tender stage along with the building tender thus impairing the available budget to carry out a proper and safe demolition. Furthermore, some Main Contractors / Owners will specify a high SALVAGE VALUE in ‘salvage cum demolition’ related projects to set off their own operation cost. In these instances, the HIGHEST SALVAGE VALUE gets the demolition project and not the demolition contractor’s track record or safety standards.
8/5/09
Report submitted
Good 2 see in today's Star that the report has been submitted by the 'PCT'. Looks like things are moving! Also looks like they're taking this very seriously, flying in engineers from Singapore and all. This is indeed good news and hopefully the development of jaya will start soon.
8/2/09
What is structural load - continue!
Dead load
The dead load is the weight of the structure acting with gravity on the foundations below. Snow load is the weight of the dead load and the imposed load but also the weight of the snow on top which could cause damage to the roof.
Live loads
Live loads, or imposed loads, are temporary, of short duration, or moving. Examples include snow, wind, earthquake, traffic, movements, water pressures in tanks, and occupancy loads. For certain specialized structures, vibro-acoustic loads may be considered.
Environmental loads
Temperature changes leading to thermal expansion cause thermal loads
Loads caused by humidity or moisture induced expansion
Ice movements
Water waves
Shrinkage
Static loads
These are loads that build up gradually over time, or with negligible dynamic effects. Since structual analysis for static loads is much simpler than for dynamic loads, design codes usually specify statically-equivalent loads for dynamic loads caused by wind, traffic or earthquake.
Dynamic loads
These are loads that display significant dynamic effects. Examples include impact loads, waves, wind gusts and strong earthquakes. Because of the complexity of analysis, dynamic loads are normally treated using statically equivalent loads for routine design of common structures. dynamic loads are also caused by aforce other than gravity
Load combination
A load combination results when more than one load type acts on the structure. Design codes usually specify a variety of load combinations together with weighting factors for each load type in order to ensure the safety of the structure under different probable loading scenarios.
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