STRUCTURAL REHABILITATION OF DAMAGED BUILDING DUE TO CRACKING

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 8, August 2018, pp , Article ID: IJCIET_09_08_136 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed STRUCTURAL REHABILITATION OF DAMAGED BUILDING DUE TO CRACKING Basim Jabbar Abbas, Hussein Yousif Aziz and Raid Tariq Hadi Muthanna University, College of Engineering, Sammawa, Iraq ABSTRACT The crack of the structure is considered as a main issue of the damaged buildings. The solutions to face this problem are different in the theory and application; therefore, it should be finding the successful and economic method compared with the reconstruction. In this paper, a real problem is presented as crack failure in building which damaged due to this reason. A proposed method is applied for a damaged building practically in the field and analysed theoretically, this method represented by using the alternative foundation instead of the damaged one to reduce the differential settlement and stopping the cracking effect on building. The alternative foundation is tried in the site and succeed to repair and rehabilitate the damage due to cracking and save the cost of reconstruction. This method can be applied for similar problems with the same mechanism considering the loading and design requirements in the field. Key words: cracks, differential settlement, rehabilitation. Cite this Article: Basim Jabbar Abbas, Hussein Yousif Aziz and Raid Tariq Hadi, Structural Rehabilitation of Damaged Building due to Cracking. International Journal of Civil Engineering and Technology, 9(8), 2018, pp INTRODUCTION Although reinforced concrete structure standard but not enough care is not always taken during construction some times less than 10 years of service live. Requiring early care and rehabilitation work [1]. A proposed repair method is to use mini pile and pile cap enlargement for improving its foundation bearing capacity, column concrete jacketing for some parts of its structure component and epoxy resin injection in the existed cracked wall [2]. To set up a rehabilitation plan for the damaged structure, a visual inspection of the damaged condition was first carried out, which was followed by analysis and on-site material tests indicating the degree of neutralization progress in the remaining structure [3]. The main issue of cracks in the structure of building is due to severe settlement of foundation. Many researchers are studied the settlement of foundations and described the phenomenon required and the suitable methods to calculate it with correct and accurate ways in addition to put correction factors and modified formulas to estimate the settlement exactly to prevent the risk developed due to its effects by which it can be safe the structure from editor@iaeme.com

2 Structural Rehabilitation of Damaged Building due to Cracking failure and damage by using the suitable design of foundation and superstructure to reduce the values of settlement because the effect of service loading [4 7]. The previous methods in the rehabilitation of damaged structures due to cracking were lack to the success application and may lead to increase the damage of the building, because cracking is an unavoidable effect of any structure while designers are trying to eliminate many of the causes of cracking and design tolerance for other factors [8]. The problem of occurring cracking should be taken into consideration in solution even it was small cracks of superficial [9]. A crack is cause for concern or not, usually, depends on circumstances, and subsequent action is needed depends on correct diagnosis of the nature of the problem which brought it about [10]. In this paper a success method is used to rehabilitee a damaged building due to cracking using the alternative foundations which will work as a supporting to the old and damage one, the benefit of using this method is to minimize the settlement occurred due to successive loading which is considered the main reason of cracks. 2. CASE STUDY The crack of structures is considered as serious problem which face the construction of buildings and regarded as main reason for failure. In this study a serious crack is occurred in constructed building and proposed methods used to solve the problem. Figures from 1 to 9 shows the cracks occurred on the walls which may attributed to not suitability of the foundation design to carry the applied loads from the super structure, therefore a hard settlement happed especially the differential settlement leading for the cracks and damage of building. In this case, there are two solutions to solve this problem. The first is to remove the building and rebuild a new one, but this choice is costly and time consuming and may be the same problem will be repeated due to the lack in the design or the bad construction. The second solution is to treat and rehabilitation of damaged building using a suitable method which will cheaper than first solution and need less time to do. The proposed method for solution is to alternative foundation instead of original foundation because the last is not suitable to carry the applied loads from the structure as mentioned before. The seismic condition of the region of study is normal with the effect of earthquake that the type of soil is sandy to sandy clay soils and it is far away from the effect of earthquake which is already happened in the north region of the country. Figure 1 The undamaged part of building Figure 2 The light outside damaged part of building editor@iaeme.com

3 Basim Jabbar Abbas, Hussein Yousif Aziz and Raid Tariq Hadi Figure 3 The hard inside damaged part of building Figure 4 The hard outside damaged part of building Figure 5 The mid inside damaged part of building Figure 6 The footing damaged part of building Figure 7 The bathroom damaged part of building Figure 8 The damaged part of building above Linton Figure 9 The W.C damaged part of building editor@iaeme.com

4 Structural Rehabilitation of Damaged Building due to Cracking 3. RESULT AND DISCUSSION The calculation procedures are of the way of treatment for the crack problem and due to the effect of building loadings. The calculation procedures were done according to ACI (2018) [11] and AISC (2017) [12]. Fig. 10 shows the shaded part of treatment which contains the building part of failure by which a differential settlement was occurred. Figure 10 The shaded area of the failure part Fig. 11 shows the treatment method used in this building for the part of foundations. The treatment consists of making new foundations laid under the old one which will work as an alternative foundation because the previous one was unsuitable to carry the applied loads. These foundations are made as reinforced beams which will be connected with a spread footing as shown in Fig. 11 which will carry the beam foundation loads that coming from the building. Figure 11 The spread footing connected with beam foundation editor@iaeme.com

5 Basim Jabbar Abbas, Hussein Yousif Aziz and Raid Tariq Hadi Fig. 12 shows the longitudinal section of the treatment which shows the spread footing connected with concrete beams and steel columns, the steel columns connected with steel beams to support the slab of the building (the details of sections are shown in Fig.12). This treatment will provide new alternative foundation suitable to carry the applied loads and support the slab and preventing the settlement of foundations especially the differential settlement which is caused the crack of building and leading to the damage the structure. Fig. 13 shows the detail reinforcement of alternative footing and spandrel beam used in the treatment. As seen in the Fig. that the excavated soil should be replaced by compacted crushed stone with 20cm thickness, compacted sub base with 95% and 20cm thickness, blinding concrete with 10cm thickness and then reinforced concrete footing with 40cm thickness and spandrel beam. The replacement of soil is necessary to modify soil properties which cause the settlement and damage of the building. Figure 12 The longitudinal section of footing connected with beam and steel columns Figure 13 The details reinforcement of alternative footing and spandrel beam

6 Structural Rehabilitation of Damaged Building due to Cracking This method of treatment is applied for damaged building due to cracks and repairs it successfully through using additional footing and structure to carry the building and stop the successive of settlement due to unsuitability of the previous foundation and weakness of soil. In the same manner Fig. 14 and Table 1 show the reinforced section of the pedestal and details steel sections used in alternative structure. Figure 14 The details reinforcement of alternative pedestal Table 1 The detail explanation of the steel sections Section Total height mm Flange width mm Web thickness mm Flange thickness mm W 10x W 8x The result of treatment shows successful method to support the deformed foundations and reduce the successive settlement and stop the cracks, instead of rebuild the building and saving the time and cost. The sustainability of rehabilitee building is more durable and reliable for the hazard effects in the future. 4. CONCLUSIONS Using the alternative foundation is benefit to resist the effect of crack damage in the building, the method proposed in this paper is successful in application and benefit to rehabilitation of buildings. The cost of rehabilitation is lower than of reconstruct the building, easy in establishing and saved the time. This method of rehabilitation can be applied for other type of construction and can be succeeded and developed using the theoretical calculation in the software application. In the same manner doing the analytical models in the rehabilitation and solving of damaged building due to cracking. The rehabilitation method used to minimize the settlement and saved the structure from damage due hazard cracking. REFERENCES [1] Varinder. K. Singh, 2013, Structural Repair and Rehabilitation of 3 no. (G+8) Multi- Storeyed residential Buildings, at ONGC colonyat Chandkheda, Ahmedabad, Gujrat. Chemical, Civil and Mechanical Engineering Tracks of the 3rd Nirma University International Conference on Engineering Procedia Engineering 51 (2013) editor@iaeme.com

7 Basim Jabbar Abbas, Hussein Yousif Aziz and Raid Tariq Hadi [2] As'ad S Mukahar Sukiman M, Investigation on wall crack damage and its proposed repair method. [3] Taehun Ha et al. A Case Study on the Rehabilitation of a Fire-Damaged Structure, applied sciences, MDPI, [4] Hussein Yousif Aziz and Jianlin Ma, Deep Foundation Numerical Analysis Using Modified Compression Modulus. The Open Civil Engineering Journal, Vol. 6, pp , 2012, ISSN [5] Hussein Yousif Aziz and Jianlin Ma, Experimental and Theoretical Static Analysis of High-Speed Railway Bridge Settlement for Deep Soft Soil The Open Construction and Building Technology Journal, Vol. 6, pp , 2012, ISSN [6] Hussein Y. Aziz, Deep Pile Foundation Settlement Prediction Using Neurofuzzy Networks, The Open Civil Engineering Journal, 2014, 8, [7] Jianlin Ma, Hussein Yousif Aziz, Chun-hui Su and Cong Shi, Settlement prediction and behavior of pile foundation in deep clayey soil deposits, Journal of Central South University,Vol. 21, Issue 4, pp , [8] Pooja Nama, Ankush Jain, Rajat Srivastava and Yash Bhatia, Study on Causes of Cracks & its Preventive Measures in Concrete Structures, Journal of Engineering Research and Applications, ISSN : , Vol. 5, Issue 5, ( Part -2) May 2015, pp [9] E. A. Jiya, N. S. N. Anwar, and M. Z. Abdullah, Detection of Cracks in Concrete Structure Using Microwave Imaging Technique, International Journal of Microwave Science and Technology, Volume 2016, Article ID , 6 pages. [10] Ron Bonshor, Lesley Bonshor and Roger Sadgrove, Cracking in buildings, Second edition, [11] ACI code, American Concrete Institute, [12] AISC code, 15th Edition AISC Construction manual, editor@iaeme.com