Kim Sang-Chul, Kim Dong-Ju, Byun Yong-Hoon
School of Agricultural Civil & Bio-Industrial Engineering, Kyungpook National University, Daegu 41566, Korea.
School of Civil, Environmental and Architectural Engineering, Korea University (Formerly Kyungpook National University), Seoul 02841, Korea.
Materials (Basel). 2021 Jun 2;14(11):3022. doi: 10.3390/ma14113022.
Fly ash, the main component for controlled low-strength material (CLSM), has physical and chemical characteristics according to the resources used in the thermal power plant, and thus fly ash type can influence the physical and strength properties of CLSM. This study investigates the effect of fly ash type on the engineering properties of CLSM and establishes relationships between mechanical properties of CLSM and shear wave velocity (SWV) for long curing times. Six fly ashes with different physical properties and chemical components are used for preparing the CLSM mixtures. The air content, unit weight, flowability, and setting time of CLSM are measured. Unconfined compressive strength (UCS) and elastic modulus (E) are obtained from unconfined compressive tests, and SWV (V) is determined using a bender element-based wave measurement system. Experimental results show that the stiffness and strength characteristics of CLSM are relevant to the contents of two oxides (SiO and AlO) and the fineness of fly ash. Because the evolution of SWV is influenced by the fly ash type, the relationships UCS-V and E-V are well established. Thus, considering the fly ash type, shear wave monitoring may be effectively used for estimating strength and stiffness characteristics of CLSM.
粉煤灰是可控低强度材料（CLSM）的主要成分，其物理和化学特性取决于火力发电厂所使用的资源，因此粉煤灰类型会影响CLSM的物理和强度特性。本研究调查了粉煤灰类型对CLSM工程特性的影响，并建立了长期养护条件下CLSM力学性能与剪切波速（SWV）之间的关系。使用六种具有不同物理性质和化学成分的粉煤灰来制备CLSM混合物。测量了CLSM的含气量、单位重量、流动性和凝结时间。通过无侧限抗压试验获得无侧限抗压强度（UCS）和弹性模量（E），并使用基于弯曲元件的波测量系统测定SWV（V）。实验结果表明，CLSM的刚度和强度特性与两种氧化物（SiO和AlO）的含量以及粉煤灰的细度有关。由于SWV的变化受粉煤灰类型的影响，UCS-V和E-V之间的关系得以很好地建立。因此，考虑到粉煤灰类型，剪切波监测可有效地用于估算CLSM的强度和刚度特性。
