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The Development of High Performance Concrete in North America
Published in Yves Malier, High Performance Concrete, 2018
Such concretes were possible because high-quality materials were available in Seattle. Both very efficient portland cement and aggregates are available there. The cement used is ASTM Type I/II portland cement, which meets the standards for Type I and II cements. It has a very low alkali content, less than 0.4% in terms of Na20 equivalent. The aggregates were from a glacial gravel pit. Aggregate particles were eroded from a very hard syenite rock. In spite of the fact that very high compressive strength has been reached with these aggregates, meticulous petrological examination revealed that some were slightly altered, leading us to conclude that 150 MPa field concrete could be reached with natural aggregates.
Shallow depth characterisation and stress history assessment of an over-consolidated sand in Cuxhaven, Germany
Published in Michael A. Hicks, Federico Pisanò, Joek Peuchen, Cone Penetration Testing 2018, 2018
V.S. Quinteros, T. Lunne, L. Krogh, R. Bøgelund-Pedersen, J. Brink Clause
The test field is located around 5 km south of Cuxhaven, Germany, approximately 6 km east of the North Sea coast (see Fig. 1). The test site is part of a sand/gravel pit, which is owned by Plambeck Erd- und Tiefbau GmbH. The pit started operations in 1980 and soil has been excavated from the area since then. Approximately 16 m to 20 m of sand has been excavated at site within the last ca. 35 years. The exact overburden height is uncertain, but based on the information provided by Plam-beck, about 18 m can be assumed as representative. Moreover, the Cuxhaven test field has also been used for research studies related to monopile installations and thus, several monopiles of 4.3 m diameter and 21 m buried length placed with 26 m distance in between (see Fig. 2) are located in the vicinity of the testing area. The specific field location chosen for testing is expected to be influenced by the monopile installations to a minor degree. An adjacent 7 m high embankment lies approximately 4 meters west of the testing area. Testing near the embankment was avoided. As seen in Figure 2, the testing area tested was circular with a diameter of 10 m. Several tests were carried out, including: CPTs, dilatometer tests, DMTs, seismic dilatometer, SDMTs, plate load tests, PLTs, nuclear densometer, ND, manual drive-in cylinder density tests, MD, as well as sampling, suction, volumetric water content and temperature. Multichannel analysis of surface waves, MASW, were performed right outside the circular testing area. The upper soil at the site is characterized by a 4.7 m thick marine fine to medium sand, overlying clay. The ground water table, GWT, was measured at 3.1 m.
Integration of Surface Water and Groundwater Rights
Published in Kathleen A. Miller, Alan F. Hamlet, Douglas S. Kenney, Kelly T. Redmond, Water Policy and Planning, 2017
Another source of augmentation water is surface water diverted in priority into lined gravel pits. Mined gravel pits are lined with a bentonite slurry wall to create a belowground impermeable barrier around the perimeter of the gravel pit from the land surface down to the bedrock. The bentonite slurry wall prevents water from escaping from within the lined reservoir and also keeps groundwater from seeping into the lake. Water is delivered into gravel-pit lakes through adjacent irrigation ditches or mechanical pumps near a river. In 1991, the first lined gravel pit for augmentation water storage was completed near Greeley.
Establishment of willows using the novel DeValix technique: ecological restoration mats designed for phytotechnologies
Published in International Journal of Phytoremediation, 2022
Ryan A. Vinhal, Ronald S. Zalesny, Brent S. DeBauche, Elizabeth R. Rogers, Andrej Pilipović, Raju Y. Soolanayakanahally, Adam H. Wiese
This study was conducted at two phytoremediation sites located in the Midwestern United States. The first DeValix buffer, located adjacent to an active municipal landfill, was 94.8 m long and was established on land previously excavated for landfill cover soil in Ontonagon, Michigan (46.7844°N, −89.1335°W). The DeValix restoration mats were installed on the banks of a small intermittent stream that provides seasonally-variable water availability. The second DeValix buffer was 121.6 m long and was established at a former gravel pit where waste dumping occurred in Manitowoc, Wisconsin (44.0594°N, −87.7199°W). The DeValix mats were installed on the slopes of an engineered retention pond that were characterized by sandy soils with little to no vegetation and low water availability. Information on native soils of both sites is presented in Table 1. Precipitation, aboveground temperature and number of growing degree days (GDD) for the 2019 growing season are shown in Figure 1.
Effectiveness of binary and ternary blended cements of class C fly ash and ground glass fibers in improving the durability of concrete
Published in Journal of Sustainable Cement-Based Materials, 2022
Omar Alsanusi Amer, Prasad Rangaraju, Hassan Rashidian-Dezfouli
Accelerated mortar bar tests (AMBT) (ASTM C1260 [30] and C1567 [31]) were conducted to evaluate the effectiveness of the tested blends of GGF and CFA to suppress ASR-induced expansion. In this investigation, rhyolitic gravel from Las Placitas gravel pit was employed as the reactive aggregate. The test was performed for all tested mixtures listed in Table 2. In each test, four 1 in. × 1 in. × 11.25 in. (25 × 25 × 285-mm) mortar bars were cast with an embedded stainless-steel gage stud at each end of the mortar bar. After demolding, the specimens were kept in water at 80 °C for 24 h, and then they were placed in 1 N NaOH solution at 80 °C as per the specification. Length change of the mortar bars was measured at periodic intervals over a test duration of 28 days. The specification requires a mortar bar expansion of less than 0.10% at 14 days of exposure in 1 N NaOH solution for the tested SCM dosage to be considered as an effective ASR mitigation.
Genesis of hummocks found in tunnel valleys: an example from Hörda, southern Sweden
Published in GFF, 2018
Gustaf Peterson, Mark D. Johnson, Sandra Dahlgren, Tore Påsse, Helena Alexanderson
Within the Hörda valley, two sections and one pit were excavated (Figs. 2 and 3). The first, Hörda I, is a former gravel pit that was abandoned after the esker gravel was mined away. The section was cleaned using a mechanical excavator into an approximately 60 m long and 4 m high section. The second section, Hörda II, was dug through a hummock lying in the center of the valley. Here, the section length was about 40 m and 4–6 m high. Furthermore, a pit was dug for till sampling and fabric measurements, which we refer to as Hörda III.