The Newcastle Flat Rigid Dilatometer (NDMT) is a new in-situ soil testing device developed in 2001 for direct measurement of the in-situ characteristics of soils such as strength, stiffness, deformation etc. It is quite simple, robust and produces repeatable data with no hysteresis. The NDMT loads the soil with a relatively rigid piston of 3 mm thickness in lieu of only 0.2 mm thick membrane of Marchetti Dilatometer (MDMT), thus creating a loading environment closer to that of the real-life foundations. The NDMT is more sensitive than the Marchetti dilatometer in measuring pressure and the corresponding displacement because of the instrumented rigid plate and therefore has the potential to detect variations in soil strength or stiffness with depth more accurately. This research paper is based on the NDMT testing at three locations in the cohesive soils of Lahore (near Thokar Niaz Beg) up to 8.0 m depth below the natural surface level. In order to correlate the NDMT test results with those of other conventional methods, SPTs were carried out and undisturbed soil samples (UDS) were recovered in thin walled Shelby tubes at locations close to the NDMT testing locations. The undisturbed soil samples were tested for grain size analysis, Atterberg limits and unconfined compression strength in the laboratory. The NDMT indices viz. material index (I_D), dilatometer modulus (E_D), and horizontal stress index (K_D) have been evaluated from the corrected load - deformation curves of each NDMT test. Subsequently, new correlations have been developed between dilatometer indices and conventional soil characteristics such as classification, undrained shear strength and elastic modulus, for the Lahore clayey silts/silty clays.
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机译：纽卡斯尔扁平刚性膨胀仪（NDMT）是2001年开发的新原位土壤检测装置，用于直接测量土壤的原位特征，如强度，刚度，变形等。它是非常简单，鲁棒的，可重复数据没有滞后。 NDMT用相对刚性活塞装载3毫米厚的活塞，代替仅0.2mm的Marketti膨胀仪（MDMT），从而产生更接近真实基础的装载环境。由于仪表刚板，NDMT比Marchetti膨胀仪更敏感，并且由于仪表化的刚性板，因此具有仪器的可能性更准确地检测土壤强度或刚度变化的可能性。本研究论文基于拉合尔的凝聚力的三个地点的NDMT测试（靠近Thokar NIAZ乞讨）高达8.0米深度低于天然表面水平。为了将NDMT测试结果与其他常规方法的结果相关联，在靠近NDMT测试位置的位置处，在薄壁的毛线管中进行，并在薄壁挡板管中回收未受干扰的土壤样品（UDS）。测试了未受干扰的土壤样品进行晶粒尺寸分析，Atterberg限制和实验室的不包含束缚的压缩强度。 ndmt indices viz。已经从每个NDMT测试的校正的负载变形曲线评估了材料索引（I_D），膨胀计模量（E_D）和水平应力索引（K_D）。随后，对于稀释计索引和传统的土壤特性，如分类，不推迟的剪切强度和弹性模量，对于拉合尔·克莱y硅淤泥/粉质粘土，已经开发了新的相关性。
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