08-10-2014, 02:14 PM
tremix flooring
[attachment=68907]
INTRODUCTION
Tremix flooring is a special type of flooring mostly being done in the industrial sector. It is generally used for industrial purposes, where rigid surface necessary for machine foundation, light load carrier vehicle and light weight cranes. By this method economic high quality concrete floors can be laid. This method improves the properties of concrete floors. Tremix flooring is also known as vacuum dewatering flooring, since in this method vacuum treatment is done to remove the surplus water is removed from the concrete.
With the industrial revolution all over the world, the floor construction has been on the serious concerns of Architect, Engineers and users. A high quality concrete floors not only be levelled perfectly but also it should have high compressive strength with minimum cost. In this flooring the water/cement ratio is drastically reduced after placing. A lowered water/cement ratio automatically leads to noticeable improvement of almost all properties of concrete. This technique is effectively used in industrial floors, parking lots and deck slabs of bridges etc. By the adoption of Tremix vacuum flooring, more workable concrete floors can be done than the normal flooring.
SPECIAL REQUIREMENTS
All the works covered by this specification has been carried out by expertise in Tremix flooring, Only skilled and experienced operators shall be employed in Tremix flooring methods. Before starting the work the engineer in charge should approve the agency. All the equipments shall be of approved and proven types and suitable for the work involved.
2.5 CONCRETE LAYING
The engineer in charge should approve the concrete laying pattern by consultation. The maximum width of a slab strip shall not generally exceed 4 meters and minimum number of construction joints shall be used. Alternate slab strips shall be sequentially laid. Any damage to the already finished top surface shall be avoided. At construction joints no overflow of mortal or slurry on the already hardened surface shall be allowed while concreting the intermediate slab strip. Such construction joints shall be marked with a thread in a straight line while the concrete is still green. Continuity of reinforcement shall be maintained while laying concrete in slab strips. Edges at expansion joints shall be protected and proper arrangement of shear-transfer shall be provided standards
CHARACTERISTICS AND PROPERTIES OF TREMIX VACCUM CONCRETE
In tremix vacuum concrete the water added should exceed the water required for the full hydration of the cement constituent. The addition water we added would used as lubricating medium to allow mixing, placing, levelling and consolidation. In conventional concreting practice, an important challenge is the prevention or limiting of evaporation of mixing water out of the freshly placed concrete. The uncontrolled removal of water from the concrete matrix can result in adverse effects such as plastic shrinkage cracking. Excessive bleeding of concrete can negatively interfere with surface characteristics such as resistance to wear. Thus the durability and service life of the flooring element is in question. Concreting in areas exposed to the elements, specifically in hot and windy conditions pose even higher demands in order to produce quality, durable concrete.
Vacuum dewatering has been patented in the USA by Billner in 1935. This process is a means to efficiently remove excess water from newly placed, compacted and levelled concrete surfaces. Vacuum treatment of concrete has been refined to specially address concreting of large exposed surfaces in hot weather conditions. It renders an economic, time-efficient compaction technique to concrete that can be placed at a medium to high workability
• Vacuum treatment of concrete based on Portland cement results in a marked increase in
compressive strength. In general, compressive strength for vacuum dewatering processed concrete is
25-45% higher at 28 days after casting. Increased flexural strength as well as a higher dynamic
modulus of elasticity are measured.
• Vacuum dewatering greatly improves the abrasion and impact resistance of the concrete surface.
Furthermore, the vacuum dewatering results in coarse aggregate in the fresh mix being drawn to the
top surface – a further contributing factor in achieving wear-resistant concrete surfaces (see the fig
3.1). The surface of vacuum treated concrete is free of pitting, an important consideration for
abrasion resistance and the possible exposure to a continuous flow of liquid over the member.
CONCLUSION
Slab depths up to 12 inches can be effectively dewatered by the vacuum process. Joint spacing can be increased because vacuum dewatering reduces shrinkage of floor slab concrete. Better use of construction manpower is possible with tremix technique because positive control of floors finishing time can be established and overtime for floor finishes can be reduced or eliminated. For suspended slabs earlier form removal is often possible because of more rapid early strength development. Tilt-up construction may be speeded by the improved early strength development achieved with tremix technique .The lowered water-cement ratio of tremix floor concrete automatically leads to drastic improvement of almost all of the concrete properties .
[attachment=68907]
INTRODUCTION
Tremix flooring is a special type of flooring mostly being done in the industrial sector. It is generally used for industrial purposes, where rigid surface necessary for machine foundation, light load carrier vehicle and light weight cranes. By this method economic high quality concrete floors can be laid. This method improves the properties of concrete floors. Tremix flooring is also known as vacuum dewatering flooring, since in this method vacuum treatment is done to remove the surplus water is removed from the concrete.
With the industrial revolution all over the world, the floor construction has been on the serious concerns of Architect, Engineers and users. A high quality concrete floors not only be levelled perfectly but also it should have high compressive strength with minimum cost. In this flooring the water/cement ratio is drastically reduced after placing. A lowered water/cement ratio automatically leads to noticeable improvement of almost all properties of concrete. This technique is effectively used in industrial floors, parking lots and deck slabs of bridges etc. By the adoption of Tremix vacuum flooring, more workable concrete floors can be done than the normal flooring.
SPECIAL REQUIREMENTS
All the works covered by this specification has been carried out by expertise in Tremix flooring, Only skilled and experienced operators shall be employed in Tremix flooring methods. Before starting the work the engineer in charge should approve the agency. All the equipments shall be of approved and proven types and suitable for the work involved.
2.5 CONCRETE LAYING
The engineer in charge should approve the concrete laying pattern by consultation. The maximum width of a slab strip shall not generally exceed 4 meters and minimum number of construction joints shall be used. Alternate slab strips shall be sequentially laid. Any damage to the already finished top surface shall be avoided. At construction joints no overflow of mortal or slurry on the already hardened surface shall be allowed while concreting the intermediate slab strip. Such construction joints shall be marked with a thread in a straight line while the concrete is still green. Continuity of reinforcement shall be maintained while laying concrete in slab strips. Edges at expansion joints shall be protected and proper arrangement of shear-transfer shall be provided standards
CHARACTERISTICS AND PROPERTIES OF TREMIX VACCUM CONCRETE
In tremix vacuum concrete the water added should exceed the water required for the full hydration of the cement constituent. The addition water we added would used as lubricating medium to allow mixing, placing, levelling and consolidation. In conventional concreting practice, an important challenge is the prevention or limiting of evaporation of mixing water out of the freshly placed concrete. The uncontrolled removal of water from the concrete matrix can result in adverse effects such as plastic shrinkage cracking. Excessive bleeding of concrete can negatively interfere with surface characteristics such as resistance to wear. Thus the durability and service life of the flooring element is in question. Concreting in areas exposed to the elements, specifically in hot and windy conditions pose even higher demands in order to produce quality, durable concrete.
Vacuum dewatering has been patented in the USA by Billner in 1935. This process is a means to efficiently remove excess water from newly placed, compacted and levelled concrete surfaces. Vacuum treatment of concrete has been refined to specially address concreting of large exposed surfaces in hot weather conditions. It renders an economic, time-efficient compaction technique to concrete that can be placed at a medium to high workability
• Vacuum treatment of concrete based on Portland cement results in a marked increase in
compressive strength. In general, compressive strength for vacuum dewatering processed concrete is
25-45% higher at 28 days after casting. Increased flexural strength as well as a higher dynamic
modulus of elasticity are measured.
• Vacuum dewatering greatly improves the abrasion and impact resistance of the concrete surface.
Furthermore, the vacuum dewatering results in coarse aggregate in the fresh mix being drawn to the
top surface – a further contributing factor in achieving wear-resistant concrete surfaces (see the fig
3.1). The surface of vacuum treated concrete is free of pitting, an important consideration for
abrasion resistance and the possible exposure to a continuous flow of liquid over the member.
CONCLUSION
Slab depths up to 12 inches can be effectively dewatered by the vacuum process. Joint spacing can be increased because vacuum dewatering reduces shrinkage of floor slab concrete. Better use of construction manpower is possible with tremix technique because positive control of floors finishing time can be established and overtime for floor finishes can be reduced or eliminated. For suspended slabs earlier form removal is often possible because of more rapid early strength development. Tilt-up construction may be speeded by the improved early strength development achieved with tremix technique .The lowered water-cement ratio of tremix floor concrete automatically leads to drastic improvement of almost all of the concrete properties .