C P A C L O W H E A T C O N C R E T E 1

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1 C P A C L O W H E A T C O N C R E T E 1

2 Õπ µ «âõπµë æ CPAC Low Heat Concrete Õπ µ π ß â ß π À à Ë π «â ß ««à 1 µ «Àπ «à 0.5 µ àπ ÕË π Õπ µ µõ àõ π ºà æßæ (Diaphragm Wall) «âõπ ªØ À«à ߪŸπ πµå πè (Heat of Hydration) Õ à ß µàõ π ËÕß àߺ ÀâÕÿ À Ÿ π π ÈÕ Õπ µ Ÿß Èπ ËßÕ «à 70 Õß» ë ß π π ºà π À à ß À «Õ «µ ßπ (ABAC 2) CPAC Low Heat Concrete placing for the mat foundation of Assumption University, Bangna Campus (ABAC 2) ë «º «πõ Õπ µ à «âõπ â Á««à π Heat on the surface is more easily transfered toward the ambient, comparatively on the center in mass concrete. 2 CPAC LOW HEAT CONCRETE ë Áπµ «Õß Õπ µ Ë à à π àõ Àâ Èß µ â «π Ë ÿ The temperature differences cause the internal restraints, becoming the later thermal contraction cracking.

3 «âõπ... Àµÿ Õß µ â «Temperature Rise... the Major Cause of Thermal Contraction Cracking «âõπ Ë π ß â ß Õπ µπ Èπ Ÿ à Ÿà πõ «âõπ ËÕ Ÿà π à ÕÕ â â «à Ë «º «Õπ µ àõ Àâ «µ µà ß Õß Õÿ À Ÿ ˺ «π ß â ß (Differential Temperature) Àâ ß â ß Õß Õπ µ À µ «Èß Ëµà ß π π Ë ÿ Õπ µ µ â «(Thermal Crack) A mass concrete is technically specified as a concrete structure with large dimensions, simply figured of greater than 0.5 metre. Those examples are such as concrete dam, large column, mat foundation and diaphragm wall etc. In general, heat in concrete member is evolved due to the hydration reaction and gradually arising in remarkable i.e. more than 70 ÌC. µ â «ß à «2 Õ 1) µ â «π π ÈÕ Õπ µ (Inobservable Crack) 2) µ ⠫˪ Æ Àâ ÀÁπ àπ (Noticeable Crack) À ß µ â «πè «Èπ ºà π ß â ß Õπ µ â À Á Àâ ß â ß à ßµ ËÕÕ «â «π π Õß ß â ß ßÕ à ß Basically, heat on the surface of mass concrete is easily released toward the ambient, whereas the center remains its high temperatures. This results the temperature difference in mass concrete, subsequently inducing the internal restraint and the subsequence thermal contraction cracking. C P A C L O W H E A T C O N C R E T E 3

4 Thermal contraction cracks occurred in mass concrete are ordinarily found in both in observable crack and noticeable crack. Consequently, it is significant that the avoidance in such the cracking must be considered. Definitely, the deterioration of concrete structure is finally found due to cracking, influencing on its durability. In addition, structure shall considerably loose its designed serviceability. «âõπ âõ à ß How to Minimise Temperature Rise CPAC Lo Concrete π «âõπ Ëß ªìπ ÀµÿÀ Õß µ â «π ß â ß Õπ µ â 3 «Õ 1) Õÿ À Ÿ Õπ µ π Ë ªìπ Õπ µ (Precooling System) ë º πè ÁßÀ Õ â π µ π À «2) «ÿ «µ µà ß ÕßÕÿ À Ÿ ˺ «π ß â ß (Temperature Difference Control) ë «âõπ Ωíß àõπè π ß â ß (Embedded Pipe Cooling) ë à â«π«π (Surface Insulation) 3) π Õß ß â ß àß (Sectioned Concreting) Èß 3 «ß à «ªìπ ªÑÕß π à à«â ªí À ˵âπ Àµÿ In terms of concrete construction, the methodology to solve this problem is so far taken in account for 3 methods: 1) Precooling of fresh concrete Mixing with crushed ice, chilled water or liquid nitrogen 2) Temperature difference control Embedded pipe cooling system in mass concrete Concrete surface insulation 3) Sectioned or split concreting for a single structure 4 C P A C L O W H E A T C O N C R E T E

5 CPAC Low Heat Concrete ß Õ À à...à ÿ ªí À µ â «CPAC Low Heat Concrete, An Innovation to Cope with Thermal Contraction Crack CPAC Low Heat Concrete Õ Õπ µæ» Ë æ «æ π Èπ æ ËÕ «ÿ ª «âõπ Ë ªØ Œ Ëπ µ ß â««ÿ ª Ë ÕÕ å Ë ªìπ ÀµÿÀ Õß «âõπ π Õπ µ æ Ë «ÿªõ π ª PFA (Pulverized Fuel Ash) â ª π à«πº Õπ µ π ªìπ«âªí À µ â ««âõπ ˵âπ Àµÿ Õ à ß â ß ªí ÿ π æ â æ π à«πº Õπ µ Õ à ßµàÕ π ËÕß æ ËÕ «ÿ ª «âõπ Ë Èπ Àâ À π Õß ß â ß ªì𠪵 âõ Àπ æ ËÕ ªí À µ â «π ß â ß Õπ µ Researched and developed on intrinsic behaviour of hydration, CPAC Low Heat Concrete shall give the limited heat by controlling unit CaO content. Based on the specified content of unit CaO, the temperature rise shall be considerably reduced, enhancing the capability effectiveness of cracking protection to control thermal contraction crack. CPAC is able to develop concrete proportioning to relevantly suit to the particular characteristics of every members as requested, simultaneously go along with other requirements. w Heat e Comparative Temperature Measured at The Centre and The Surface of Foundation with A Depth of 2.50 metres. Concrete Temperature ( c) Normal Concrete Elapsed time (days) CPAC Low Heat Concrete C P A C L O W H E A T C O N C R E T E 5

6 CPAC Low Heat Concrete ÿ µ Ë àπ CPAC Low Heat Concrete, Outstanding Properties CPAC Low Heat Concrete ÿ µ Ë àπ «à Õπ µ Ë«ªÕ à ß ÀÁπ â 1) «â æ Ë Èπ â«õπÿ Ë Õß PFA Àâ CPAC Low Heat Concrete Ëπ À µ «â ªÕ Ÿà À«à ß À Á ËÀπ πàπ â Àâ È à Õπ µ âßà ª æ Èπ «ß π π«π ßß π Ëß à«µâπ ÿπ π Õπ µ «2) È µ «À µ «π ËÕß «ÿªõ π à«æ Ë «â Õß Õπ µ Àâ Ëß Èπ Àâ ª πè π à«πº ß â ß à«è µ «À µ «Õß Õπ µ 3) ßÕ π «Ÿß «à Õπ µ Ë«ª Õπ ÕÕ å (SiO 2 ) π«ÿªõ π ªØ Œ Õ å [Ca(OH) 2 ] Ë À Õ ªØ Œ Ëπ â ª Õ µ Œ µ (CSH) Õ ÈßÀπ Ëß ß ë Õπÿ «ÿªõ π Pozzolan Particles ë Õπÿ πµå Cement Particles Cement + H 2 O CSH + Ca(OH) 2 (Hydration Reaction) SiO 2 + Ca(OH) 2 CSH (Pozzolanic Reaction) ªØ ªÕ π Õ à ßµàÕ π ËÕß ªìπº Àâ æ π ßÕ Õß Õπ µ À ß 28 «π ß ß π π µàõ ª ß Àâ ßÕ π «Õß CPAC Low Heat Concrete «à Õπ µ Ë«ª 4) «π π «µâ π π àõπ ß æ Ë Èπ π ËÕß ªØ ªÕ π Ë Èπ À⪠µ «ËÕ ª π (CSH) æ Ë Èπ ß Àâ CPAC Low Heat Concrete π ÈÕ πàπ Èπ πè Èπ àߺ Àâ ß â ß «Áß ß π π âß π â «π π 6 C P A C L O W H E A T C O N C R E T E

7 Its properties are clearly superior beyond conventional concrete as the following ; 1) Excellent Workability, With spherical particle, a pozzolan, additive in concrete, enables concrete more workable. The compaction can be done more conveniently, with preferable quality. Distinctively, time and cost saving would be also achieved. 2) Reducing Bleeding and Drying Shrinkage, A reduced water content is applied in the proportion due to use of pozzolan, therefore bleeding, segregation and drying shrinkage are unquestionably controlled. 3) Higher Long Term Strength, In pozzolanic reaction, SiO 2 reacts with Ca(OH) 2, by product of hydration reaction, to yield an additional CSH as shown in below equation. Pozzolanic reaction is continually developed over 28 days of concrete ages, as a result, long term strength would be gained, having been higher than normal concrete. 4) High Durability, Having additional cementitious, low permeability, fundamental of durability, is obviously satisfied. Comparative Strength Development between CPAC Low Heat Concrete and Normal Concrete Relative Strength Development (%) Normal Concrete CPAC Low Heat Concrete Ages of Concrete CPAC Low Heat Concrete C P A C L O W H E A T C O N C R E T E 7

8 ÿâ à «à â«cpac Low Heat Concrete Distinctive Worthy...CPAC Low Heat Concrete The Other Means in Temperature Control àß ß â ß Sectioned or Split Concreting º πè ÁßÀ Õ π µ π À «Mixing with crushed ice or liquid nitrogen Ωíß àõπè Embedded pipe cooling à â«π«π Insulated Curing Comparative Benefits in Use of CPAC Low Heat Concrete «ßß π à â à π µ ß π µà Èß ªí À Õ µàõ À«à ß Èπ Õπ µ (Construction Joint) Reducing in both construction time and labouring Saving in preparation of each concrete placing Eliminating problems of cold joint À ªí À ËÕß «ÿ Õÿ À Ÿ Õß Õπ µ À«à ß àß à â à π À πè Áß π µ π À «No need of temperature control in concrete delivery Saving in procurement cost of crushed ice or liquid nitrogen «ÿàß π Ωíß àõπè µ µ Èߪíö πè «à â à No complicated procedure of piping and water pump installation Saving in both construction time and cost â ßÕ Ÿß «à à â à π º ËÕ ßÕ ªØ Œ Ëπ Ë à Ÿ å «Ë ß Õÿ À Ÿ Ë µ µà ß π Having higher strength Saving cost in case of use higher strength No risk of high temperature difference 8 C P A C L O W H E A T C O N C R E T E

9 π π ÿ æ ⫺ Õ Õÿ À Ÿ Assured with Resultant Concrete Temperature Rise Measurement ß π π ºà π À à (Mat Foundation) π Õ øøñ À Õ µ ß π àß «π ÿß æ À π (BTS) π «â ß 8.40 µ «38.40 µ 4.75 µ Ëß Õ«à ªìπ π Ë Ë ÿ πª» Ë Èß «æ «à Õÿ À Ÿ Ë«â Ÿß ÿ Õ 72 Õß» à µ µà ß Ÿß ÿ À«à ß ß ß â ß «º «æ ß 25 Õß» Mat foundations of Morchit Depot of Bangkok Transit System (BTS) is regarded as mass concrete with dimensions of 8.40 x x 4.75 metres. Such the depth, 4.75 metres, is the deepest in Thailand for a single concrete placing. ë µ µ ÈßÕÿª å«õÿ À Ÿ π π ß π àß «π ÿß æ À π (BTS) Installation of Temperature measuring equipment in the deepest mat foundation of BTS Morchit Depot The results of temperature measurement show the peak temperature of 72 ÌC and the temperature difference between surface and center of only 25 ÌC. Resultant Temperature of Mass Concrete for BTS Concrete Temperature ( c) Center Surface Elapsed time (days) C P A C L O W H E A T C O N C R E T E 9

10 CPAC Low Heat Concrete «Ëπ Õß ÿ ß CPAC Low Heat Concrete...Confidences of all projects à«πàπ Ëß Õß ß Ë Ëπ Õ â 1. ß π àß «π ÿß æ À π (BTS) 2. ß øøñ À π (MRTA) 3. ß ß øøñ ÿ 4. ß À «Õ «µ ßπ (ABAC 2) 5. ß π π Õ æ Á å 6. ß «Õ π 7. ß øøñ à«π Ÿ ß π 8. ß æ ßß π TRI IPP 9. ß æ ßß π Ààß µ ÿ 10. ß àõπìè ß ë ß π àß «π ÿß æ À π (BTS) Bangkok Transit System (BTS) Some reference projects assured to take CPAC Low Heat Concrete as a part in their works. 1. Bangkok Transit System (BTS) 2. Metropolitan Rapid Transit Authority 3. Ratchaburi Power Plant 4. Assumption University, Bangna Campus (ABAC 2) 5. Millenium Complex 6. Valmet Technology 7. Provincial Electric Supply Authority, Headquarter Office 8. TRI IPP Energy Project 9. Thai National Power, Chonburi 10. Chachoengsao Raw Water Supplying Project ë ß ß øøñ ÿ Ratchaburi Power Plant 10 C P A C L O W H E A T C O N C R E T E

11 ë ß À «Õ «µ ßπ (ABAC 2) Assumption University, Bangna Campus (ABAC 2) ë ß øøñ À π (MRTA) Metropolitan Rapid Transit Authourity ë ß π π Õ æ Á å Millenium Complex C P A C L O W H E A T C O N C R E T E 11

12 12 CPAC LOW HEAT CONCRETE