การใช้คอนกรีตรีไซเคิลสำหรับการก่อสร้างในอนาคต

งานวิจัยนี้เสนอแนะการใช้โพลีเมอร์เชือกเสริมเส้นใยธรรมชาติ เพื่อเสริมกำลังเสาคอนกรีตสี่เหลี่ยมรวมรีไซเคิลที่ประกอบด้วยอิฐมวลรวมแข็งจากดินเหนียวเผา เพื่อลดต้นทุนสูงที่เกี่ยวข้องกับโพลีเมอร์เสริมใยสังเคราะห์ ตัวอย่างคอนกรีตจำนวน 24 คอลัมน์เพื่อทำการศึกษาครั้งนี้ ตัวอย่างได้รับการทดสอบภายใต้แรงอัดตามแนวแกนแบบโมโนโทนิก ตัวแปรที่น่าสนใจคือ กำลังของคอนกรีตไม่จำกัดจำนวน และจำนวนชั้น FRR จากผลการทดสอบ ชิ้นงานที่ได้รับการปรับปรุงให้แข็งแกร่งขึ้นแสดงให้เห็นถึงกำลังรับแรงอัดและความเหนียวที่เพิ่มขึ้น โดยเฉพาะอย่างยิ่ง ชิ้นงานที่มีความแข็งแรงไม่จำกัดน้อยที่สุดแสดงให้เห็นถึงการปรับปรุงที่ใหญ่ที่สุดในด้านกำลังรับแรงอัดและความเหนียว โดยเฉพาะกำลังรับแรงอัดและความเครียดเพิ่มขึ้นถึง 181% และ 564% ตามลำดับ เพื่อที่จะคาดการณ์ความเครียดและความเครียดจากแรงอัดที่จำกัดขั้นสุดท้าย การศึกษานี้จึงได้ตรวจสอบแบบจำลองความเครียด-ความเครียดเชิงวิเคราะห์จำนวนหนึ่ง การเปรียบเทียบผลการทดลองและทางทฤษฎีสรุปได้ว่าแบบจำลองความแข็งแกร่งเพียงจำนวนจำกัดเท่านั้นที่ส่งผลให้เกิดการคาดการณ์อย่างใกล้ชิด ในขณะที่มีการสังเกตการกระจายที่ใหญ่กว่าสำหรับการทำนายความเครียด การเรียนรู้ของเครื่องถูกนำมาใช้โดยใช้โครงข่ายประสาทเทียมเพื่อทำนายกำลังรับแรงอัด ชุดข้อมูลที่ประกอบด้วย 142 ตัวอย่างเสริมความแข็งแกร่งด้วยกัญชา FRP ถูกดึงออกมาจากวรรณกรรม โครงข่ายประสาทเทียมได้รับการฝึกอบรมเกี่ยวกับชุดข้อมูลที่แยกออกมา และประสิทธิภาพของมันได้รับการประเมินสำหรับผลการทดลองของการศึกษานี้ ซึ่งแสดงให้เห็นถึงข้อตกลงที่ใกล้ชิด

Earthquakes are among the most unpredictable and catastrophic natural hazards. Thousands of earthquakes occur every year due to ongoing seismic activity in the earth crust because of sudden release of stored elastic strain energy in the Earth’s lithosphere. Several hundred weak earthquakes, with magnitude of 2 or smaller on the Richter scale, occur every day worldwide [1]. Earthquakes are not only fatal for human lives but also cause colossal and sometimes unrepairable damage to buildings, infrastructure and other facilities, leaving a huge number of people homeless or without shelter. During the 21st century, earthquakes left more than 12.5 million people homeless with their houses either destroyed or heavily damaged. Masonry construction is very common across the world and both unreinforced and reinforced masonry is opted for construction purposes. Masonry structures are brittle in nature and most earthquake prone class of building particularly unreinforced masonry. Heavy damage to the existing structures, high death tolls, number of injured and displaced people in the case of masonry buildings during the past earthquakes verifies the vulnerability of this type of construction [2]. In Feb 2011, a 6.3 magnitude earthquake that occurred approximately 10 kilometers away from the city center hit Christchurch in New Zealand. Even though it was a moderate earthquake, smaller than a past earthquake of 7.1 magnitude of Sep 2010, the damage caused to the buildings was much devastating due to higher ground shaking levels in the city. Among all building types, unreinforced masonry buildings performed the worst and suffered the highest damages [3] In many countries including Thailand, masonry was an integral part of building construction for ages. In the past, masonry was being used for construction of load bearing walls in low and medium rise buildings as well as for cladding and partition walls. Apart from residential facilities, masonry was also commonly used for a wide range of buildings including educational, industrial and commercial buildings. There are several benefits of masonry wall construction including load bearing, resistant to weather changes, fire protection, sound and thermal insulation [4-8]. Masonry construction is generally durable that stays serviceable for a long time, easy to work with and it can also be utilized for architectural and aesthetic purposes. The high demand of construction of buildings gives reason to find ways to fulfill and to solve the problems related to the construction. Interlocking bricks is an alternative system which is similar to the “LEGO blocks” that use less or minimum mortar to bind the bricks together [9-15]. Interlocking bricks were introduced to reduce the use of manpower, hence fulfill the requirement of Industrialized Building System (IBS). Interlocking brick system is a fast and cost-effective construction system which offers good solution in construction. In Thailand, cement-clay interlocking (CCI) bricks made of locally available clay are widely used to construct low rise residential buildings throughout the country [16-21]. These interlocking bricks are manufactured locally in small factories located in different regions of Thailand. At present, there are at least 700 brick manufacturing plants in Thailand [22]. In the past, different researchers have investigate the structural response of the CCI brick masonry walls. For example, Joyklad and Hussain (2018) conducted a very detailed experimental study on the axial and diagonal compressive response of the CCI bricks masonry walls. The results indicate that the structural of the CCI brick masonry walls is very weak especially under pure diagonal compression [23, 24]. In another study, Joyklad and Hussain (2020) studied lateral response of cement clay interlocking brick walls by testing large scale CCI brick masonry walls subjected to lateral earthquake loading. Experimental results indicate very poor performance of CCI brick masonry walls against lateral loading. The recorded lateral drifts were very small and CCI brick masonry walls were failed due to sliding and crushing of the CCI bricks [25]. Both above studies indicate that in-plane ultimate failures of CCI brick masonry walls are very vulnerable against both static and lateral cyclic loading. Thus, the ultimate failures of CCI brick masonry walls in another direction i.e., out-of-plane direction could be much more dangerous and vulnerable. Further, in the event of an earthquake the failure of masonry walls in out-of-plane direction could cause heavy damage. A detailed review of existing studies indicate that no research effort has been conducted on the flexural strengthening of CCI brick masonry walls to enhance the load carrying capacity and ductility of the CCI brick masonry walls in the out-of-plane direction. There is an urgent need to explore the efficiency of low-cost and locally available techniques to enhance the load resistance capacity and ductility of CCI brick masonry wall in out-of-plane direction. This study is proposed to investigate the use of expanded metal mesh and fiber glass polymer composites for flexural strengthening of CCI brick masonry walls. For this purpose, a large-scale experimental program is planned in which a total number of 26 CCI brick masonry walls will be constructed and tested in out-of-plane direction to investigate the efficiency of expanded metal mesh and fiber glass polymer composites to enhance the load resistance and ductility of CCI brick masonry walls. References: 1. How Often Do Earthquakes Occur? Incorporated Research Institutions for Seismology Available at: https://www.iris.edu/hq/inclass/fact-sheet/how_often_do_earthquakes_occur. 2. Roser, M. & Ritchie, H. Natural Catastrophes. (2018). Available at: https://ourworldindata.org/natural-catastrophes. 3. Moon, L. M., Griffith, M. C., Dizhur, D. & Ingham, J. M. Performance of unreinforced masonry structures in the 2010/2011 Canterbury earthquake sequence. in 15th world conference on earthquake engineering (15WCEE): Lisbon, Portugal (2012). 4. Likelihood of Earthquakes in Thailand. Chula International Communication Center. Available at: http://www.cicc.chula.ac.th/eng/2012-04-26-04-23-32/111-likelihood-of-earthquakes-in-thailand.html. 5. Løvholt, F. et al. Earthquake related tsunami hazard along the western coast of Thailand. (2006). 6. Tsuji, Y. et al. The 2004 Indian tsunami in Thailand: Surveyed runup heights and tide gauge records. Earth, planets Sp. 58, 223–232 (2006). 7. Bang Niang police boat. Electrostatico (2006). Available at: https://www.flickr.com/photos/electrostatico/321172469/in/set-72157594418089264/. 8. Ruangrassamee, A. et al. Investigation of tsunami-induced damage and fragility of buildings in Thailand after the December 2004 Indian Ocean tsunami. Earthq. Spectra 22, 377–401 (2006). 9. Documents on Ecological Disasters. Department of Mineral Resources of Thailand. Available at: http://www.dmr.go.th/ewt_news.php?nid=6814. 10. A 6.0 Magnitude Earthquake Hits Northern Thailand, Causing Significant Damage. The International Information Center for Geotechnical Engineers (2014). Available at: https://www.geoengineer.org/news-center/news/item/815-6-3-magnitude-earthquake-hits-northern-thailand-causing-significant-damage. 11. Earthquake in Northern Thailand. Kompasiana (2014). Available at: https://www.kompasiana.com/bangkokblogger/gempa-bumi-di-thailand-utara_54f76a01a3331189338b47d0. 12. Experts Say Thailand Not Prepared for Another Eathquake Like Chiang Rai. Chiang Rai Times (2015). Available at: https://www.chiangraitimes.com/experts-say-thailand-not-prepared-for-another-earthquake-like-chiang-rai.html. 13. Thai earthquake. The Baltimore Sun (2014). Available at: http://darkroom.baltimoresun.com/2014/05/a-big-red-shoe-the-vaticans-elite-swiss-guard-earthquake-in-thailand-israeli-independence-day-may-6/thai-earthquake-2. 14. Ruangrassamee, A., Ornthammarath, T. & Lukkunaprasit, P. Damage due to 24 March 2011 M6. 8 Tarlay earthquake in Northern Thailand. in 15th world conference on earthquake engineering (15WCEE): Lisbon, Portugal (2012). 15. Shakir, A. A., Naganathan, S. & Mustapha, K. N. Properties of bricks made using fly ash, quarry dust and billet scale. Constr. Build. Mater. 41, 131–138 (2013). 16. Sadek, D. M. Physico-mechanical properties of solid cement bricks containing recycled aggregates. J. Adv. Res. 3, 253–260 (2012). 17. Kadir, A. A. & Mohajerani, A. Physical and mechanical properties of fired clay bricks incorporated with cigarette butts: Comparison between slow and fast heating rates. in Applied Mechanics and Materials 421, 201–204 (Trans Tech Publ, 2013). 18. Karaman, S., Ersahin, S. & Gunal, H. Firing temperature and firing time influence on mechanical and physical properties of clay bricks. (2006). 19. Binici, H., Aksogan, O. & Shah, T. Investigation of fibre reinforced mud brick as a building material. Constr. Build. Mater. 19, 313–318 (2005). 20. Mechanical Properties of Interlocking Block with Coconut Shell Ash. in The 8th National Conference on Technical Education (2014). 21. Charoennuekul, C. Interlocking Blocks Containing Oil Palm Ash and Shells Waste. J. Community Dev. Life Qual. 2, 103–112 (2014). 22. Hendry, A. W. Reinforced and prestressed masonry. (Longman Scientific & Technical, 1991). 23. JOYKLAD, P., & HUSSAIN, Q. (2019). Performance of Cement Clay Interlocking Hollow Brick Masonry Walls Subjected to Diagonal Compression. Journal of Engineering Science and Technology, 14(4), 2152-2170. 24. Joyklad, P., & Hussain, Q. (2019). Axial compressive response of grouted cement–clay interlocking hollow brick walls. Asian Journal of Civil Engineering, 20(5), 733-744. 25. JOYKLAD, P., & HUSSAIN, Q. (2020). LATERAL RESPONSE OF CEMENT CLAY INTERLOCKING BRICK MASONRY WALLS SUBJECTED TO EARTHQUAKE LOADS. Journal of Engineering Science and Technology, 15(6), 4320-4338.