Effect of surcharge load on Microbial-Induced Calcite Precipitation (MICP) treatment of tropical peat

11th Curtin University Technology, Science and Engineering (CUTSE) International Conference

工业技术（总论）

Phang, Ignatius Ren Kai^1 ; Wong, Kwong Soon^1 ; Chan, Yen San^2 ; Lau, Sie Yon^2

Department of Civil and Construction Engineering, Curtin University Malaysia, CDT 250, Miri, Malaysia^1

Department of Chemical Engineering, Curtin University Malaysia, CDT 250, Miri, Malaysia^2

关键词: Caco3 precipitations;    Calcite precipitation;    Metabolic pathways;    Ordinary Portland cement;    Submerged condition;    Surcharge preloading;    Unconfined compression tests;    Unconfined compressive strength;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/495/1/012068/pdf
DOI  :  10.1088/1757-899X/495/1/012068

学科分类：工业工程学

来源: IOP

【 摘 要 】

Peat is known as problematic ground with low bearing capacity and extensively high compressibility. Ordinary Portland cement (OPC) and lime were usually used to tackle unfavourable characteristics of peat by improving it with its cementation effect. However, little was known of the effect of bio-cementation towards peat improvement. Bio-cementation or commonly known as Microbial-induced calcite precipitation (MICP) has been recently introduced as a ground improvement alternative for geotechnical engineering application. MICP performed by utilising metabolic pathways of non-pathogenic urealytic bacteria that precipitates calcium carbonate (CaCO3) crystal as cementation binder that seal soil particles together increasing soil strength. MICP of inorganic soil was extensively explored, and only limited was done for organic soil. This study explores on the effect of different surcharge preloading of 18kPa, 36kPa and 48kPa towards Microbial-Induced Calcite Precipitation (MICP) treatment of tropical peat. Fibrous peat studied were obtained from Miri, Sarawak and cured under a submerged condition with different vertical preload for seven days. Laboratory study including unconfined compression test, quantification of carbonates precipitated, and moisture content of stabilised specimens was observed to evaluate the performance of stabilisation effort. Unconfined compressive strength (UCS) of treated specimens was observed to be higher than untreated specimens with the highest increase of UCS up to 469%. However, CaCO3 precipitation amount for this study was observed to decrease with increasing surcharge preload.