Pub Date : 2020-05-26DOI: 10.47890/jceid/2020/sisarsam/12045784
S. Sarsam, Zahraa Ahmed Samor
Cold mix asphalt concrete is considered as a sustainable and green pavement, the aggregates and the binder can be mixed, laid, and compacted without consumption of energy. In this investigation, an attempt has been made to prepare cold mix asphalt concrete for base course construction. Two types of liquid binder, named Cationic emulsion Medium Setting CMS and Medium Curing cutback MC-250 have been implemented in preparation of Marshall specimens. Four types of additives, named Portland cement, coal fly ash, limestone dust and hydrated lime have been tried. Mixtures were subjected to aeration, then compacted. However, Specimens were subjected to curing before testing. It was concluded that mixtures with (optimum cutback content + 5% cement and 4 hours aeration and 24 hours curing at 60°C) and (optimum emulsion content +2% hydrated lime +3% cement or fly ash and 4 hours aeration at 25°C and 24 hours curing at 60°C) satisfies the volumetric and Marshall properties requirements for base course. It was recommended that increasing the aeration and curing periods is beneficial for the cold mix asphalt concrete in satisfying the specification requirements for base course. Keywords:Cold Mix; Asphalt Concrete; Cement; Lime; Fly ash; Marshall; Aeration; Curing;
{"title":"Evaluation of Cold Mix Asphalt Concrete Properties","authors":"S. Sarsam, Zahraa Ahmed Samor","doi":"10.47890/jceid/2020/sisarsam/12045784","DOIUrl":"https://doi.org/10.47890/jceid/2020/sisarsam/12045784","url":null,"abstract":"Cold mix asphalt concrete is considered as a sustainable and green pavement, the aggregates and the binder can be mixed, laid, and compacted without consumption of energy. In this investigation, an attempt has been made to prepare cold mix asphalt concrete for base course construction. Two types of liquid binder, named Cationic emulsion Medium Setting CMS and Medium Curing cutback MC-250 have been implemented in preparation of Marshall specimens. Four types of additives, named Portland cement, coal fly ash, limestone dust and hydrated lime have been tried. Mixtures were subjected to aeration, then compacted. However, Specimens were subjected to curing before testing. It was concluded that mixtures with (optimum cutback content + 5% cement and 4 hours aeration and 24 hours curing at 60°C) and (optimum emulsion content +2% hydrated lime +3% cement or fly ash and 4 hours aeration at 25°C and 24 hours curing at 60°C) satisfies the volumetric and Marshall properties requirements for base course. It was recommended that increasing the aeration and curing periods is beneficial for the cold mix asphalt concrete in satisfying the specification requirements for base course. Keywords:Cold Mix; Asphalt Concrete; Cement; Lime; Fly ash; Marshall; Aeration; Curing;","PeriodicalId":165066,"journal":{"name":"Journal of Civil Engineering Inter Disciplinaries","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131407474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-20DOI: 10.47890/jceid/2020/selrefaie/12045783
E. S., S. M.
Extending lifts` reinforced concrete cores to foundations usually restricts services and lobby functions of a building. A core supported on columns at core`s corners is considered a good alternative for sorting out this problem. However, this will cause an abrupt reduction in the lateral stiffness of the building below the cores level i.e. soft story vertical irregularity. Hence, large lateral displacement of the building is expected causing its instability and potentially results in its collapse. No caution at seismic response parameters (for instance, lateral story drift ratio) is found in the current codes for buildings having soft stories. The ratio between the lateral stiffness of a given story and that of a story / three stories above is the only parameter found in current codes, for example UBC and ASCE7 codes, to identify a soft story criterion. In this paper, the seismic response of a building due to change in the level at which the central core is planted and the distribution of the columns supporting it is investigated. Partial support of reinforced concrete cores via underneath columns is found to be an effective means of enhancing the lateral stiffness of the building and reducing its lateral side sway. This effect is extremely dependent on the level of the soft story i.e. the level at which the cores are planted. The phenomena of the UBC and ASCE7 codes for identifying the soft story in a building needs to be revised. Keywords: Soft Story; Seismic Loads; Vertical Irregularity; Drift Ratio; Concrete; Cores;
{"title":"Seismic Response of Buildings with Soft Story","authors":"E. S., S. M.","doi":"10.47890/jceid/2020/selrefaie/12045783","DOIUrl":"https://doi.org/10.47890/jceid/2020/selrefaie/12045783","url":null,"abstract":"Extending lifts` reinforced concrete cores to foundations usually restricts services and lobby functions of a building. A core supported on columns at core`s corners is considered a good alternative for sorting out this problem. However, this will cause an abrupt reduction in the lateral stiffness of the building below the cores level i.e. soft story vertical irregularity. Hence, large lateral displacement of the building is expected causing its instability and potentially results in its collapse. No caution at seismic response parameters (for instance, lateral story drift ratio) is found in the current codes for buildings having soft stories. The ratio between the lateral stiffness of a given story and that of a story / three stories above is the only parameter found in current codes, for example UBC and ASCE7 codes, to identify a soft story criterion. In this paper, the seismic response of a building due to change in the level at which the central core is planted and the distribution of the columns supporting it is investigated. Partial support of reinforced concrete cores via underneath columns is found to be an effective means of enhancing the lateral stiffness of the building and reducing its lateral side sway. This effect is extremely dependent on the level of the soft story i.e. the level at which the cores are planted. The phenomena of the UBC and ASCE7 codes for identifying the soft story in a building needs to be revised. Keywords: Soft Story; Seismic Loads; Vertical Irregularity; Drift Ratio; Concrete; Cores;","PeriodicalId":165066,"journal":{"name":"Journal of Civil Engineering Inter Disciplinaries","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133167688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-14DOI: 10.47890/jceid/2020/sisarsam/12045782
S. Sarsam, Samah Abdulrazzaq AL Nuaimi
The asphalt concrete flexible pavement consists of many layers interconnected by tack coat binder. The resistance of the bonding tack coat to the impact of moisture that ingress through the cracks into the interface of asphalt concrete can cause premature matrix degradation of pavement structure. In this investigation, the influence of moisture susceptibility on the bond strength and horizontal deformation of three layers of asphalt concrete are assessed under repeated shear stresses. The suitability of two types of tack coat (Rapid curing cutback RC-70 and medium setting cationic emulsion CMS) to support the resistance to moisture damage have been investigated. Asphalt concrete slab specimens have been prepared with the aid of roller compactor for the typical three layers usually implemented in flexible pavement in Iraq (wearing, binder and asphalt stabilized base courses) with (12, 19.5 and 25) mm nominal maximum size of aggregate. Layers were bonded by tack coat after construction of the bottom layers. Core specimens have been obtained and subjected to moisture damage then practiced 1200 cyclic shear stresses in the Pneumatic Repeated Load System PRLS using a special manufactured mold. Control core specimens have been obtained and practiced 1200 cyclic shear stresses. Specimens were tested for bond shear strength. The bond shear strength and horizontal deformation under repeated shear stresses were analyzed and compared. It was concluded that the horizontal permanent deformation increases by a range of (4 -27) % and (2-57) % after moisture damage when RC-70 and CMS tack coat were implemented respectively at various application rates. However, the reduction in bond shear strength due to moisture damage ranges between (2-17) % and (5 -30) % for RC-70 and CMS Tack coat interfaces. CMS tack coat exhibits higher bond shear strength ratio BSSR than RC-70 tack coat for all the application rates and is recommended for use from the moisture susceptibility point of view. Keywords: Moisture Susceptibility; Interface; Asphalt Concrete; Bond Shear; Horizontal Deformation; Tack Coat;
{"title":"Assessing the Moisture Susceptibility at Interface of Asphalt Concrete Pavement Layers","authors":"S. Sarsam, Samah Abdulrazzaq AL Nuaimi","doi":"10.47890/jceid/2020/sisarsam/12045782","DOIUrl":"https://doi.org/10.47890/jceid/2020/sisarsam/12045782","url":null,"abstract":"The asphalt concrete flexible pavement consists of many layers interconnected by tack coat binder. The resistance of the bonding tack coat to the impact of moisture that ingress through the cracks into the interface of asphalt concrete can cause premature matrix degradation of pavement structure. In this investigation, the influence of moisture susceptibility on the bond strength and horizontal deformation of three layers of asphalt concrete are assessed under repeated shear stresses. The suitability of two types of tack coat (Rapid curing cutback RC-70 and medium setting cationic emulsion CMS) to support the resistance to moisture damage have been investigated. Asphalt concrete slab specimens have been prepared with the aid of roller compactor for the typical three layers usually implemented in flexible pavement in Iraq (wearing, binder and asphalt stabilized base courses) with (12, 19.5 and 25) mm nominal maximum size of aggregate. Layers were bonded by tack coat after construction of the bottom layers. Core specimens have been obtained and subjected to moisture damage then practiced 1200 cyclic shear stresses in the Pneumatic Repeated Load System PRLS using a special manufactured mold. Control core specimens have been obtained and practiced 1200 cyclic shear stresses. Specimens were tested for bond shear strength. The bond shear strength and horizontal deformation under repeated shear stresses were analyzed and compared. It was concluded that the horizontal permanent deformation increases by a range of (4 -27) % and (2-57) % after moisture damage when RC-70 and CMS tack coat were implemented respectively at various application rates. However, the reduction in bond shear strength due to moisture damage ranges between (2-17) % and (5 -30) % for RC-70 and CMS Tack coat interfaces. CMS tack coat exhibits higher bond shear strength ratio BSSR than RC-70 tack coat for all the application rates and is recommended for use from the moisture susceptibility point of view. Keywords: Moisture Susceptibility; Interface; Asphalt Concrete; Bond Shear; Horizontal Deformation; Tack Coat;","PeriodicalId":165066,"journal":{"name":"Journal of Civil Engineering Inter Disciplinaries","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123389133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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