Allahyarham Mohd Azlan Hamid

Rakan-Rakan semua, saya baru balik ziarah Sahabat kita, keadaan amat tenang sekali, suasana persekitaran kampung amat sesak dengan jiran-jiran dan rakan-rakan menziarahi arwah. Saya sempat menatapi wajah arwah dan sayu rasanya sehingga tidak sedar mengalir keluar air mata. Wajah arwah berseri dan ahli keluarganya tenang. Cuma terdengar tangisan anak kecil yang mungkin belum memahami keadaan ini.

Al-Fatihah kepada Allahyarham Mohd Azlan. Semoga rohnya dicucuri rahmat.

AL-FATIHAH

Rakan-Rakan X-UiTM 1991 - 1993,
Sahabat kita Mohd Azlan Hamid (Pak Lan) telah meinggal dunia pada pukul 9.00 malam tadi. Pemergiannya amat dirasai. Rasanya baru semalam terdengar riuh-rendah dengan kata-kata yang melucukan tetapi boleh dijadikan renungan dan pedoman. Sama-sama kita mendoakan Semoga Rohnya dicucuri Rahmat. Al-Fatihah.

Ini Baru Dinamakan Innovatif Teknologi

Untuk renungan bersama Rakan-Rakan

Ravelling

What is Ravelling?

Ravelling is the loss of surface aggregate from a bituminous surfacing mixture. Ravelling affects the integrity of the mix. If it is not halted it may cause deterioration to the extent where the surfacing mix no longer performs competently, resulting in a lack of waterproofing and causing an uncomfortable ride.

What Causes Ravelling?

Causes of ravelling can be dirty aggregate, segregation on the surface and poor compaction. In the case of dirty aggregate the bitumen sticks to the dust not to the stone and thus traffic can flick out the poorly held stone. In areas where the grading is deficient in fines, the coarse aggregate is effectively depleted of binder. As the binder ages the bond weakens, or stripping occurs. This rips the coarse aggregate out.

Poor compaction can also be a cause of raveling. Cohesion may be too low and the material will fret away under traffic.

Pavement Defect - Bleeding

Bleeding refers to the accumulation of asphalt binder (cement) on the pavement surface - normally in the wheelpath areas. Bleeding can be caused by excess asphalt cement and/or insufficient voids in the asphalt mix, with the excess asphalt being flushed to the pavement surface by wheel loads during hot weather. Pavement areas affected by bleeding reduce the friction available for aircraft braking and can become very slippery - especially when wet.

COLD IN-PLACE RECYCLING

This innovative road reconstruction process is a cost-effective alternative to more traditional methods of rebuilding asphalt roadways. It is used when existing pavement has aged, cracked or deteriorated beyond the point that normal road maintenance operations are practical or cost effective.

With single-unit Cold In-Place Recycling Train, a highly-efficient milling machine excavates the existing asphalt pavement to a depth of 75mm - 300mm to eliminate cracks, ruts and oxidized asphalt. The down-cutting action of this specially-designed milling machine sizes the asphalt and immediately blends it with a specially-formulated asphalt emulsion. This emulsion mixes with the milled pavement and acts as a binder to form the new recycled asphalt pavement. Finally, this new mixture is placed on the roadway by a bituminous paver and compacted as a new and more durable 75mm - 300mm asphalt base course. This new base course is placed at the grade and cross-slope as required by project specifications.

Major road detours and obstructions normally associated with road reconstruction are eliminated with the Cold In-Place Recycling Process. This entire reconstruction takes place in a single lane at a time, allowing traffic to flow unimpeded around the recycling operation. Access into and out of driveways can be provided during construction so deliveries and businesses are minimally interrupted. Another positive aspect of this process is that all of the construction is conducted within a span of approximately 30 to 40m. This relatively small work area can greatly reduce the delay time motorists generally experience in conventional construction work zones.
Following a brief curing period of approximately one week, a surface course of new hot mix asphalt 40mm to 60mm in depth is applied on top of the recycled base to complete the road reconstruction process. The thickness of the new surface mix placed over the recycled base will depend upon the use and traffic loading of the area being reconstructed.

Cold In-Place Recycling has been used since the early 1980's to reconstruct nearly every type of asphalt-based roadway. These projects include "farm-to-market" roads that were constructed without a proper asphalt base, busy residential roads, urban commuter thoroughfares, and major feeder systems for industrial parks. Some roads completed with this process now handle in excess of 15,000 to 20,000 vehicles per day.

Cold In-Place Recycling can be used to rehabilitate all types of asphalt pavement including airport taxiways/runways and parking lots for heavy industrial, commercial and institutional uses.

THE BENEFITS OF COLD IN-PLACE RECYCLING INCLUDE;

ENVIRONMENTALLY SUPERIOR CONSTRUCTION

• No Asphalt is Wasted - 100% is efficiently reused
• Natural resources are preserved
• Landfill space is not taken up by a recyclable resource

MINIMAL USER IMPACT

• Faster reconstruction
• Road that could have taken weeks to rebuild can be recycled in just a few days or less.
• Less commuter delay
• In most cases, the recycled road remains open to traffic throughout the reconstruction. Residents are minimally affected
• Businesses remain open and deliveries can be maintained
• Emergency services and bus transportation continue with minimal delay

LOWER COST

• A typical Cold In-Place Recycling project is one-half to one-third the cost of traditional total reconstruction methods
• In US, Cold In-Place Recycling saves taxpayers over $300 million each year.

STRONGER ROADS

• Recycling builds thicker asphalt bases, providing roads with a stronger foundation and renewing their lifespan to that of their original construction

Cold In-Place Recycling is one of the fastest growing road reconstruction techniques available. It is fast, cost-efficient, and can produce a strong base course using existing road material. When your asphalt roads have deteriorated to the point that they need to be reconstructed, consider utilizing Cold In-Place Recycling to build a stronger road base, save tax dollars, minimize traffic delays, and help conserve our valuable natural resources.

FAQ ON CiPR

How do I know if my road is a good candidate for Cold In-Place Recycling(CiPR)?

• Generally speaking, any asphalt roadways with good structural strength coupled with at least 100mm - 150mm of existing asphalt material are good candidates. However, each road must be evaluated on an individual basis to determine whether or not it is a good candidate for the process. Use of this process for heavy-duty roads or high-speed, high-traffic roads may not be appropriate.
  

What types of additives are used in the process?

• The most common additive is asphalt emulsion; however, lime slurry, portland cement, fly ash or a combination of these additives are also used.

What types of problems can recycling correct?

• Recycling can correct problems such as rutting, raveling, polishing of aggregates, bleeding, shoving as well as poor profiling. Basically any type of surface defect.
  

How long will a recycled road last?

• Most properly designed recycled pavements last as long as a comparable virgin hot-mix pavement.
  

How thick/deep can you cold recycle?

• The equipment is limited to 250mm - 300 mm. However, the primary limitation is curing and compaction. The deeper you cold recycle, the more compaction equipment is necessary. Also, aeration may be necessary for curing on deep recycle projects.

What does the end product look like?

• The end product usually looks like a base paving material. In some cases a fog seal is placed on the surface which protects it from the elements as well as giving the material a uniform black surface appearance.
  

How much additive is used?

• The amount of additive is determined by the mix designs from material sampled from the roadway. Typical asphalt emulsion contents range from 13% by weight of the RAP. When cement or lime are used typical application rates are from 13%. When fly ash is the additive the application rate varies from 5 - 12%.
  

How much can I save using CIPR?

• Typically cost savings vary from 25% to 33% over other equivalent alternatives.

What are the environmental benefits of CIPR?

• No heating is used during the process thereby reducing the use of fossil fuels and also reducing air pollution. Also, the existing aggregate and asphalt cement is reused thereby decreasing and/or eliminating the need for virgin aggregate and asphalt cement in the process. Total energy savings of from 40% to 50% can be achieved using this processes versus conventional approaches.
  

What are the traffic restrictions during and after construction?

• Traffic is kept off the finished product until compaction is complete. There is no need to wait for the material to cool or setup because it is not heated. This helps facilitate the speedy return to traffic and reduces user delays. The recycled lane may be opened to traffic one hour after completion of the day's work.
  

How many years has the process been used?

• Various forms of cold recycling have been used for many years. The advanced cold recycling systems with sophisticated processing and additive controls have been around since the early 1980's.
  

Can the process be used at night?

• CIPR has been used at night. Depending on the type of additive in use and the weather conditions curing may be slower. However, it has been successfully performed.
  

What are the weather and temperature limitations?

• The weather and temperature limitations will vary depending on the additives in use. Generally, asphalt emulsions are used when the temperature is 18ºC and rising and the conditions are not rainy or wet. Each project should be evaluated individually by a local expert to determine its viability.
  

What surfacing do you apply?

• It is recommended that all Cold In-Place Recycling projects receive a seal or overlay. A pavement design is required to determine how much if any overlay is necessary.
  

How soon may a surface course be applied?

• It is generally recommended that the moisture content of the recycled material not be greater than 1.5 % above the "free moisture" content of the original existing pavement before overlay or sealing. Light fog seals are commonly placed the same day as construction, however.
  

Can you reprofile the road?

• A certain amount of reprofiling may be performed with the Cold In-Place Recycling process. Severe geometrical problems cannot be rectified without premilling the surface prior to Cold In-Place Recycling.
  

Are specifications available?

• Yes, JKR/SPJ/2008-S4

Preventive Maintenance

Preventive maintenance is a schedule of planned maintenance actions aimed at the prevention of breakdowns and failures. The primary goal of preventive maintenance is to prevent the failure of equipment before it actually occurs. It is designed to preserve and enhance equipment reliability by replacing worn components before they actually fail. Preventive maintenance activities include equipment checks, partial or complete overhauls at specified periods, oil changes, lubrication and so on. In addition, workers can record equipment deterioration so they know to replace or repair worn parts before they cause system failure. Recent technological advances in tools for inspection and diagnosis have enabled even more accurate and effective equipment maintenance. The ideal preventive maintenance program would prevent all equipment failure before it occurs.

Value of Preventive Maintenance

There are multiple misconceptions about preventive maintenance. One such misconception is that PM is unduly costly. This logic dictates that it would cost more for regularly scheduled downtime and maintenance than it would normally cost to operate equipment until repair is absolutely necessary. This may be true for some components; however, one should compare not only the costs but the long-term benefits and savings associated with preventive maintenance. Without preventive maintenance, for example, costs for lost production time from unscheduled equipment breakdown will be incurred. Also, preventive maintenance will result in savings due to an increase of effective system service life.

Long-term benefits of preventive maintenance include:

• Improved system reliability.
• Decreased cost of replacement.
• Decreased system downtime.
• Better spares inventory management.

Long-term effects and cost comparisons usually favor preventive maintenance over performing maintenance actions only when the system fails.

When Does Preventive Maintenance Make Sense

Preventive maintenance is a logical choice if, and only if, the following two conditions are met:

• Condition 1: The component in question has an increasing failure rate. In other words, the failure rate of the component increases with time, thus implying wear-out. Preventive maintenance of a component that is assumed to have an exponential distribution (which implies a constant failure rate) does not make sense!
  
• Condition 2: The overall cost of the preventive maintenance action must be less than the overall cost of a corrective action. (Note: In the overall cost for a corrective action, one should include ancillary tangible and/or intangible costs, such as downtime costs, loss of production costs, lawsuits over the failure of a safety-critical item, loss of goodwill, etc.)
  

If both of these conditions are met, then preventive maintenance makes sense. Additionally, based on the costs ratios, an optimum time for such action can be easily computed for a single component.