Sinabung erupted

KARO - Sinabung region Karo, North Sumatra, yesterday (29 / 8), precisely at 00:08, erupted. The eruption occurred twice. Hot lava began to come down to the foot of the mountain.
Journalists Sumut Pos (Java Post Group) reported that bursts of dust and smoke caused the dark village. Road dust smell of sulfur filled the alias of sulfur. Plants are also covered in dust. In addition, visibility is only 3-5 meters. The smell of sulfur from the smoke and dust suffocating breathing. 

Thousands of residents in a radius of six kilometers from the summit of the mountain was gradually displaced. About 12,000 residents of 12 villages in four districts on the slopes of the mountain were evacuated to the agency house regents pendapa Karo in Kabanjahe. Some were evacuated in Jamburta Ras, Berastagi.
"All citizens of the (residential, Red) radius of six kilometers had to be evacuated," said Head of Volcanology and Geological Hazard Mitigation (PVMBG) Geological Agency Surono in supervisory posts Sukanalu Village, District Naman Teran, Karo, yesterday. Command Post was located about four kilometers from the discharge location magma. 

When mountain with height 2400 meters above sea level it erupted, out incandescent material. Lava is causing thick smoke as high as 1500 meters. "I do not know if this (yesterday, Red) preceded the earthquake. Therefore, I see only the mountain," explained Surono. 

Hot lava from the crater accompanied Sinabung dust out since Saturday night (28 / 8). A resident saw the fire emanating from the top of the mountain last Saturday at around 11:50pm. "Now look radiant heat, once the red upward. Never before. Only the smoke," the resident said.
Seeing the incident, he said, villagers panicked. In addition, those who have gone out of their homes confused what to do. 

According to him, belonging to his village some distance from the top Sinabung. But the villagers have been evacuated to Berastagi and Kabanjahe.
From City Berastagi, hot lava was clearly visible. Residents had flocked out of the house to witness such a natural event. Some residents Berastagi also began to flee to other areas.
Meanwhile, with improvised equipment, hundreds of villagers on the slopes located Sukanalu Sinabung return displaced. "Who lives in the village most adult males only, keeping the house from theft," said Sitepu, a local resident. Some refugees went to the home department and the regents Karo buildings or jambur meeting in Kabanjahe.
At least 500 residents Sigaranggarang Village, Kuta Rakyat, Bekerah Simacem, Gutagugung, and Sukanalu still displaced in Tanah Karo pendapa regents house on Jalan Veteran, Berastagi.
Residents fled to seek refuge with pendapa it since Friday (27 / 8) at 8:00pm. To meet the needs of dawn, most Muslim citizens who make a common kitchen in the vicinity pendapa.
President SBY Sinabung monitor conditions through the Special Staff Division of Disaster and Social Assistance Andi Arief. According to Andi, now there are officers of the National Disaster Management Agency (BNPB) and local governments as well as a team of experts from which to evacuate Jakarta residents. "I have been coordinating with the chairman BNPB. Commandos in the hands of regents Karo," he said.
In another part, PVMBG set Sinabung as volcano type A. Sinabung alert status or its activity is now at level IV. The status was upgraded after the spraying of hot lava when the volcano erupted yesterday. "Because of type A, we will monitor 24 hours," said Surono. Previously, volcanic eruptions and the nature Sinabung not recorded since 1600.
From the refugee camps, reported the majority of citizens began to esophageal ARI (acute respiratory infections) and diarrhea. Until Sunday afternoon, waves of refugees are still arriving.



*The News is translated from Jawa Post Newsletter , August 30, 2010

Dowel Bar

Dowel is a tool that is used to connect the slab by slab, slab concrete with asphalt pavement, which serves to lock the plate edges and reduce the occurrence of crack between the concrete.

• First type is dowel bar connection. This dowel has two types of connections made from a plain which is made of steel dowel connections and the connection end of the dowel. Dowel connections installed in the middle of slab concrete, while the connection is installed at the edge of the dowel end slab concrete. The difference between them lies in the length of anti-rust coating.  

• Second type is dowel with a tie bar which serves to lock the top edge slab concrete (end). The dowel is using steel threaded connections without grease.

• Third type is dowel with the crack inducer that functions to reduce the occurrence of cracks in slab concrete and between slab concrete.

• Fourth type is dowel as expansion joint.

• Fifth type is connection with the thickening of the edge of the tie bar. This connection is used on the plate with the transition between the concrete pavement with asphalt pavement.

Self Compacting Concrete on Suramadu Approach Bridge Project

Initially the Suramadu Bridge Approach Project, the basis for planning to use concrete pile bore under water. But in practice, because the condition of pile bore so deep, the weight of the concrete itself will push the concrete. Fresh concrete will be crushed because the pressure from the weight and meet the formwork. So generally bore pile of concrete near the criteria of SCC though not a concrete SCC.

 

Self-Compacting Concrete (SCC) is a type of concrete that does not require the placement of vibration. SCC can flow due to their own weight and put itself in the formwork with a good compaction. SCC began to be used because of the need for concrete that has durability and high strength continues to grow. Many studies have been conducted to determine the standards for SCC, but until now has not obtained standard for SCC. However, the main problem of SCC has resolved most of the preparation method of mix-design and workmanship field testing method that can reach the SCC.

There are some conditions on the site that by using the SCC would be more helpful than the implementation using ordinary concrete. Those are:

a. Concreting carried out in the water 

Condition that the project was in the middle of the ocean into consideration for the use of concrete that requires no vibration. Because to prevent segregation of concrete required vibration in concrete placement or compaction. Bore pile conditions that has the depth to 80m below the water surface is not possible to be done on concrete vibration. The best solution is to use SCC, because it can flows with their own weight and can meet all of the formwork with a good compression, even int the formwork are tightly spaced reinforcement though.

b. Reduce the use of workforce

By using the SCC, the amount of labor used will be reduced, because the SCC can flow evenly the weight of their own without the help of many workers. But the special training necessary in the existing workforce to create the appropriate mix of standard SCC.

The objectives of SCC:

a. Fast implementation

b. Quality homogeneous

c. Reducing human involvement in the case of compaction

d. Avoiding brittle due to concreting mistake

e. Good for location difficult to reach, even though meeting with tight reinforcement.