Tuesday, August 12, 2008

MRR2: The forgotten Heroes!

S.O.S. Letter to Ministry of Works in 2004

Cadangan Projek Jalan Lingkaran Tengah II – Pakej 11 (MRR2)
Conclusion and Recommendation, concerning the Cracks in Crossheads

The longitudinal cracks are not a negligible problem of torsion during construction.

The lack of transverse reinforcement is a safety risk for the final stage.

The calculated safety factor is far below 1.0.

Internal redistributions of forces and alternative load paths due to yielding of the reinforcement, intensively cracking and plastification of compression zones of the concrete prevented a collapse so far.

The structure is not stable.

Emergency and safety measures should urgently be undertaken. deformation measurement and installation of strain gages at transverse reinforcement is recommended.

Please inform your client about our serious concerns.

best regards

Markus Maier
Leonhardt, Andra & Partner

The above is the letter from the German Consultant to our Malaysian authority.

Did you all know how serious it was at that time in 2004? This letter was written to our govt in August 2004.

The Government did not treat it as a matter of crisis. It took the govt until February 2006 to decide to take action. They didn't care about preventing the possibility of catastrophic failure as reported by Dr Robert L. Vollum of Halcrow. They don't care about thousands of people that will be dead of this catastrophic failure occurs.

Only after Dr Wahid was appointed as the Director-General of PWD did he pushed for the repair and remedial work to be completed within 3 months.

The group of JKR engineers together with the workers worked 24 hours each day for more than 90 days. They work in 2 shifts - 12 hours each shift to meet the target set by PWD.

They did complete the repair works, all within 3 months. Samy Vellu was surprised how they managed to do it. But he never said a word of appreciation until today.

Look at the pictures below:

These pictures were taken at 3am in the middle of the night.

Each night the German senior engineer from Leonhardt, Andra & Partner (LAP) together with the JKR senior management and JKR engineers would meet at the project site to discuss the works schedule, the details and the problems encountered. More than 90 litres of grout was pump into the concrete beams to grout the understrength porous concrete.

Where were you at 3am? Were was Samy at 3am? You may be surprised that the D-G of JKR was there almost every night around 3am with the workers at MRR2 site.

These are the people who work 24 hours a day for 90 days to repair the MRR2. They completed the works in 90 days.

What were the recognition for these people?

Why was the govt not thankful and appreciative of their commitment, contribution and sacrifices.

They were living for 3 months without spending time with their family members. They had to abandoned their wife, children and parents so as to ensure that the MRR2 repair works are completed within the 3 months.

And at the end, there was not even a word of thanks from the Works Minister Samy Vellu nor from the Prime Minister and Deputy Prime Minister. Today, all of them lives in obscurity after serving the nation.

The PM and DPM showed tremendous concerned for Saiful; but they didn't even cared for the a group of people who had sacrificed for the nation - these were the heroes who work hard to prevent a catastrophe from occurring.







Note:

The flyover is safe. Only Pier 28 has some problem with the plastic straps which are used to encased the grouts used to seal the pre-stressed wire-ropes which provides the necessary reinforcements to strengthen the crossbeams which had failed. The repair for the defective works are in progress and the consulting engineers from LAP have inspected the defects and recommended the necessary repair.

Incidentally, Pier 28 was the first Pier that was repaired in 2006. As such, there may had been some initial problem due to the learning process as the repair contractor is not experienced in this methodology of structural strengthening works. Immediately after observing the contractor's weakness, JKR utilized a team of senior engineers to closely monitor the quality of works and ensured that the remaining works meets the strict specified requirements.

Thursday, August 7, 2008

MRR2 FAILURES: Would the TRUTH be told?

Yesterday, sun2surf columnist Citizen-Nades in his article "Former minister wins uncivil war" wrote:

[quote]

The asking price by the new firm – Leonard Andre and Partners (LAP) was a mere RM18 million – just RM6 million more and they were providing space-age technology – carbon-fibre to save the cracking pillars.

Can we anticipate someone standing up and saying: "Yes, I take responsibility. It was me who approved the use of carbon-fibre technology which had never been tested or used in Malaysia previously."

[unquote]

I would like to tell Nadeswaran that Carbon-Fibre Technology (CFRP) is not space-technology and the proposed methodology for strengthening the reinforced concrete structure using CFRP is not something new and surely is not a space-technology, neither is it used for the first time in Malaysia.

The peeling of the plastic strap do not mean the strengthening works had failed. It is neither about taking responsibility for a failed technology or methodology. If ever we are to discuss failure, we should be discussing about the structural failures which was occasioned by the design failure during the construction stage.

How many of us gets to know the truth of the failure? To make matter worse, we have non-engineers who were fed with surreal knowledge of engineering design and construction technology. Equally we are puzzled by the statement made by Halcrow senior consultant (bridge engineering) Roger Bucky who said he had in 2005 advised PWD not to use carbon fibre straps because the plastic straps used to strengthen the pillars have limited ductility; but JKR proceeded with the use of the carbon fibre straps.

3 of the 18 carbon fibre straps on Pillar 18 had since peeled off.

Roger Bucky in his diagnosis attributed delayed ettringite formation (DEF) as the cause of the peeling of the straps.

For non-structural engineers they may think that DEF is some kind of a cancerous virus in structural concrete. So what is DEF?

Generally, DEF is seen as a form of internal sulphate attack. A number of factors such as concrete composition, curing conditions and exposure conditions influence the potential for DEF. DEF is believed to be a result of improper heat curing of the concrete where the normal ettringite formation is suppressed. The sulfate concentration in the pore liquid is high for an unusually long period of time in the hardened concrete. Eventually, the sulfate reacts with calcium and aluminium containing phases of the cement paste and the cement paste expands. Due to this expansion empty cracks (gaps) are formed around aggregates. The cracks may remain empty or later be partly or even completely filled with ettringite.

(Source: www.concrete-experts.com)

Self-desiccation of normal density (ND) high strength concrete may prevent delayed ettringite formation (DEF).

Was DEF as espoused by Halcrow the reason of the structural failures? It wasn't!

So what cause the failure? What caused the cracks in the crossbeams?

The investigation carried out by the experts into the cracking has comprised of both field investigations and design assessment. The field investigations included site inspections; data gathering; crack mapping; cover-meter tests, concrete strength sampling; chemical tests and crack width monitoring.

The design assessment comprised of both load assessment and structural analysis by a number of methods including Code Assessment, 2D Strut and Tie Modelling, and Non-Linear Finite Element Modelling. The analysis covered both construction phase loading (from temporary overhead erection loading used to erect the precast superstructure segments) and in–Service Phase loading from permanent loads and traffic.

Based on Site Investigations and Design Assessment, the primary causes of the cracking at the critical sections for the Typical Piers and Abutment B are a result of temporary gantry erection loading and early thermal and shrinkage cracking which occurred during the Construction Phase. These load conditions were far more onerous for the structure than any In-Service load conditions.

For the In-Service Phase, calculations by both traditional Bernoulli methods and by Strut and Tie methods have demonstrated that the Pier structure has more than the required capacity to carry the factored In-Service loads in-accordance with BS 5400 Code requirements.

In the analysis the development of bond stresses in the reinforcing bars has been checked and found to comply with Code requirements.

The FE Model predicts that the Ultimate Capacity of the pier cantilever is in the order of 2.6 times the applied Nominal Loads, which far exceeds the Code required factor of safety. Ultimate failure at this level of overload is ductile as required by the Code. Sudden failure would not occur even at this extreme overload condition.

This was the structural analysis reported. However, the recommended solution was not acceptable and was considered as superficial. The engineers wanted a comprehensive rectification methodology, which would ensure that the structural integrity would comply with the Need Statement and in accordance with the Government's Requirement as postulated in the Contract Document. JKR holds the contractor fully responsible for the default which constituted a breach of contract and wanted the contractor to make good the defective works in full compliance of the agreed design integrity.

Under the PWD From DB/T Contract Terms and Conditions, it was stipulated that the Contractor shall check the design and accept responsibility (Read Clause 2.3.2).

As stipulated under Clause 2.2 of the Conditions of Contract: "The Contractor shall be fully responsible for the design, execution and maintenance of the Work/portion of the Works for which the design have been accepted by the Government, and shall absolutely guarantee the Government independent of fault that the design, materials and workmanship for the Works or portion of the works is suitable for the known requirement of the Government."

Under Clause 2.6, The Contractor shall take full and unequivocal responsibility for the safety of the design and for the adequacy, stability and safety of all site operations and methods of construction.

And in Clause 2.7.1, the Contractor shall be liable for any damage to the Works occasioned by him in the course of any operations carried out by him.

Clause 2.8.4 states that, if there is any failure, either during the execution of the Works or during the Defect Liability Period, any remedial or repair works shall, in the opinion of the Project Director (Ketua Pengarah JKR) be urgently necessary for the safety of the Works or the public, the Government may employ and pay other persons to carry out such work or repair as the PD may consider necessary; and the costs and charges properly incurred by the Government in so doing shall be recoverable from the Contractor by the Government.

Nadeswaran posed the question: "Who is going to be held accountable for this monumental man-made disaster?"

Mr. Nades, who else? There is a contract and the contract had spelt out the terms and conditions. The German structural engineers had confirm it was design error. The British Halcrow had confirmed it was design fault. The Australian Consultant had reported that the causes of cracking were due to negligence in their design work which have resulted in the design failure. The primary causes of the cracks at the critical sections for the Typical Piers and Abutment B are a result of temporary gantry erection loading and early thermal and shrinkage cracking which occurred during the Construction Phase. Both of these design effects were in the scope of design works provided under the terms and conditions of contract.

So, who else should be responsible? Who is going to be accountable?

I'm sorry; it would have to be the contractor.

I hope Samy Vellu do not come up with another different version of explanation. Let's wait for him to tell us.




Wednesday, August 6, 2008

MRR2: Halcrow said the cracks was due to DEF

Halcrow's senior consultant (bridge engineering) Roger Buckby said the primary cause of the cracks was the delayed ettringite formation (DEF)




Collepardi said: in the absence of any of these elements (as shown in the diagram above), DEF-related deterioration cannot occur.

Below is the DEF crack pattern:








Below is the crack pattern on Pier 28:








How can this be due to DEF?

MRR2: Wrong Material used for repair

Halcrow senior consultant (bridge engineering) Roger Bucky said he had in 2005 advised PWD not to use carbon fibre straps because the plastic straps used to strengthen the pillars have limited ductility; but JKR proceeded with the use of the carbon fibre straps.

3 of the 18 carbon fibre straps on Pillar 18 had peeled off.

The primary cause of the peeling was due to delayed ettringite formation (DEF). DEF is believed to be a result of improper heat curing of the concrete to strengthen a structure.

Halcrow was engaged to conduct a study on cracks on MRR2 in 2004.

Monday, August 4, 2008

MRR2: 3rd repair job to start on 5th Aug 2008


Good News! MRR2 has been re-paired!

The concrete will not fall anymore and the road is safe for traffic.

See - the traffic is flowing down-under! It's safe!

We do not know how much it has cost the government this time for the re-pair undertaken. I hope it is not $70m again.

Anyway, the Crossbeam looks nice and environmental friendly.

Deputy Director-General of Public Works I Datuk Mohamad Husin said in a statement today that preliminary works are to begin tomorrow on the cracks which have appeared on Pier 28. The decision was reached at a meeting of Public Works Department (JKR) experts, representatives of the consultant and the contractor here today.

BTW, Datuk Mohamad Husin was the Ketua Pengarah Cawangan Jalan when the repair work was implemented, and he was the Superintendent Officer in-charge of the repair works carried out by Bridgex Sdn Bhd and supervised by German Leonhardt Andra & Partner, the expert structural repair consultant. He should have a better understanding of the current problem as well as the historical database of the repair and strengthening works done at that time. He is the best person to know why it is failing.

Sunday, August 3, 2008

MRR2 cracks again - Third Time closure of Flyover!

Middle Ring Road II Cracks Again!

This is the 3rd time!

After repairing it for RM70 million and engaging the German experts on the strengthening job, the fear of this concrete structural failures is back!

Today the police have to closed the flyover in Kepong to all traffic and the road below it after cracks appeared on a pillar.

City Deputy Traffic Chief DSP Ng Fook Long said today that police closed that section of the MRR2 at 10.30am following a directive from the Public Works Department (JKR) and Kuala Lumpur City Hall (DBKL), adding that the cracks had appeared on Pillar 28.

A driver of the RapidKL bus service, Zainuddin Mohamad Taib, 37, said he was informed by another driver that he saw small stones falling from the flyover as he passed under it at 3.30 am. He said the police were informed.

This is the third time the 1.7-km MRR2 Kepong flyover has been closed because of cracks.

It was first closed in August 2004 and then for the second time in February 2006 for repairs.

(Source: NST and TheStar)


Halcrow Group Ltd, the British consultant appointed by the government to investigate the defects reported that it was a design flaw and improper anchorage of crossbeams on the concrete columns that caused cracks in 31 pillars of the MRR2.

This report was disclosed by the then Works Minister Samy Vellu at a press conference in Parliament on the 30th Sept. 2004.

Halcrow’s report was prepared by its bridge engineering director Roger J. Buckby and submitted to the Work’s Minister.

Samy Vellu had in August 2004 shot down questions of a design fault.

After receiving the Halcrow’s report, Samy finally admitted that it was the contractor’s fault as this is a Design and Built Contract awarded under the DB/T (2002) Contract Form.

The Halcrow report states that:

“The main cause of excessive cracking in the crosshead to the T-shaped pier is a deficiency in the design and the anchorage of the columns reinforced into the crosshead. There is also a deficiency in the design of the transverse reinforcement in the top of the crossheads to resist splitting forces between bearings. The horizontal cracking in the crosshead directly above the columns is a direct result of the inadequate anchorage of the column bars into the crosshead.”

Tan Sri Zaini Omar was the then Director-General of JKR who was in-charged of this project. He had since then retired and is now involved in the UEM-Penang 2nd Bridge Project and the Water Commission.


The Cabinet then decided to appoint a German consultant to spearhead repair work on the Middle Ring Road 2 in Kepong.

As reported on NST Feb. 22nd 2006, Works Minister Datuk Seri S. Samy Vellu said the decision was reached at the Cabinet meeting and the ministry’s secretary-general is discussing with the consultants on the conceptual layout of the work plan, which will be ready by the end of March 2006.

"They have assured us that the repair work on 31 pillars would be completed in 4 1/2 months," Samy said.

The cost is expected to be more than RM40 million. Samy Vellu said the cost was initially estimated to be around RM18 million but it has more than doubled after it was decided that all the 31 pillars need to be repaired simultaneously.

The flyover was finally re-opened on December 8th 2006 to traffic.

Samy Vellu said the remedial work, which began in March was completed on schedule, that is, December 2006. Samy may have forgotten that he had earlier stated that it will take 4 1/2 months from march, which should have been August, to be exact. Nevertheless, December wasn't that late.

On the February 1st, 2007, It was reported in TheStar that total repair cost was more than RM70 million, and not RM40 million.

THE Public Accounts Committee (PAC) has revealed that repairs to the MRR2 flyover in Kepong cost more than RM70mil.

The then PAC chairman Datuk Shahrir Abdul Samad said the figure was high compared with its construction cost – RM120mil.

He was quoted as saying that this reflected “shoddy design and construction concepts” that were approved by the Government when projects were given to contractors.

“There is no point in spending more and not being able to use it,” he said, adding that it was difficult to pinpoint who was responsible for the mistakes in such a project.

“As an example, the MRR2 project has the contractor and concessionaire constantly pointing fingers at each other. The problems were with the design and construction.”

Till today we do not understand why Shahrir Samad said it was difficult to point who was responsible for the mistakes in this project. This project is a Design-Built Contract under DB/T Standard Forms of Contract.

As stated in Clause 2.2 of the Contract: "The Contractor shall be fully responsible for the design, execution and maintenance of the Work/portion of the Works for which the design have been accepted by the Government, and shall absolutely guarantee the Government independent of fault that the design, materials and workmanship for the Works or portion of the works is suitable for the known requirement of the Government."

Under Clause 2.3.2, it is stated that the Contractor shall check the design and accept responsibility.

In Clause 2.6, it is stated that: "The Contractor shall take full and unequivocal responsibility for the safety of the design and for the adequacy, stability and safety of all site operations and methods of construction.

And in Clause 2.7.1, the Contractor shall be liable for any damage to the Works occassioned by him in the course of any operations carried out by him.

Under Clause 2.8.4, if there is any failure or event occurring in connection with the Works, or any part thereof, either during the execution of the Works or during the Defect Liability Period, any remedial or other work or repair shall, in the opinion of the Project Director (JKR D-G) be urgently necessary for the safety of the Works or the public and the Contractor fails to immediately do such work or repair, the Government may employ and pay other persons to carry out such work or repair as the PD may consider necessary; and the costs and charges properly incurred by the Government in so doing shall be recoverable from the Contractor by the Government.

The Government paid for the RM70 million from taxpayers' money and had never recovered any.

Now, we don't know how much more it will cost; and there may be possibility that the structure will have to be further strengthened by another RM70 million; Oops! the costs has now increased sharply since then. Ask JKR and you will know.

By the way, we now have a new Works Minister (Dato' Ir Mohd Zin Bin Mohamed) and a new PWD Director-General (Datuk Seri Professor Ir Dr Judin bin Abdul Karim). Both are certified Chartered Engineers. Let's hope they will come up with an effective solution. Who is going to pay? Contractors or Government again?

Note:

Package 11 of the MRR2 which covers a 4km stretch and cost RM238.8mil to build.

MRR2 was built by Sukmin Sdn Bhd, Bumihiway (M) Sdn Bhd and Konsortium Kontraktor Melayu (Wilayah).








Picture Source: The Star Gallery