Liquefaction Mitigation of Silty Sands with MICP

Liquefiable soils require remediation to reduce the consequences of liquefaction. Methods used for improving sands can become restricted when applied to silty sands. These restrictions include lower permeability, environmental impacts, and higher costs. Therefore investigating the application of a new and more natural soil improvement method which can overcome these restrictions is necessary. Microbial induced calcium carbonate precipitation (MICP) is a natural and sustainable soil improvement method which increases the soil's strength and stiffness. In this project, MICP is applied to study the changes in the undrained monotonic and cyclic shear response of silty sands with varying levels of fines content (0 to 35%). Dry pluviation method was applied to prepare the soil specimens using mixtures of Nevada sand and silica flour. The untreated specimens were consolidated under the effective stress of 50 kPa and then sheared. The MICP treated specimens were first consolidated under 15 kPa of effective stress and treatment was performed to achieve a shear wave velocity of about 400 m/s. Once treatment was finished, the specimens were consolidated under 50 kPa of effective stress. All specimens were sheared with a rate of 50% strain per hour. The calcium carbonate content of MICP treated specimens were measured using acid washing. The data herein presents the reduced data and information such as specimen height, cross sectional area, mass of soil, void ratio, calcium carbonate content, shear wave velocity, consolidation volume change, strain rate, cyclic stress ratio (CSR) and number of cycles to liquefaction (N). The datasets can be used by researchers who study the experimental and numerical liquefaction response of untreated and MICP treated silty sands.可液化土壤需开展加固处理，以降低液化引发的灾害后果。现有砂土改良方法应用于粉砂时往往存在诸多局限，诸如渗透性能下降、环境负面影响显著以及成本居高不下等。因此，研发可克服上述局限的新型天然土壤改良方法颇具必要性。微生物诱导碳酸钙沉淀（Microbial Induced Calcium Carbonate Precipitation, MICP）是一种天然可持续的土壤改良技术，可有效提升土体强度与刚度。本研究采用MICP技术，针对细粒含量介于0至35%的不同配比粉砂，探究其不排水单调剪切与循环剪切响应的变化规律。本研究采用干式落砂法，以内华达砂与硅粉的混合试样开展制样工作。未加固试样先在50 kPa有效应力下进行固结，随后开展剪切试验；经MICP加固的试样则先在15 kPa有效应力下固结，随后进行加固处理直至其剪切波速达到约400 m/s。待加固完成后，再将试样置于50 kPa有效应力下进行二次固结。所有试样均采用每小时50%应变的剪切速率开展剪切试验。经MICP加固试样的碳酸钙含量采用酸洗法进行测定。本数据集包含经整理后的各类试验数据与信息，具体包括试样高度、横截面积、土体质量、孔隙比、碳酸钙含量、剪切波速、固结体积变化量、剪切应变率、循环应力比（Cyclic Stress Ratio, CSR）以及液化循环次数（N）等。本数据集可供研究未加固及MICP加固粉砂液化响应的试验与数值模拟研究者使用。

搜集汇总

背景与挑战

背景概述

该数据集聚焦于使用微生物诱导碳酸钙沉淀（MICP）技术来减轻粉质砂土的液化风险，通过实验研究不同细粒含量（0-35%）样本在MICP处理前后的单调和循环剪切响应变化。数据包括钙碳酸盐含量、剪切波速度、循环应力比等关键参数，旨在为研究人员提供粉质砂土液化响应的实验和数值分析基础，强调MICP作为一种可持续、自然的土壤改良方法。