Background The use of anchors fixed in sandy soil is currently pioneering, especially in fixing the sides of excavations or marine structures, and even in engineering structures exposed to lateral loads. Therefore, there is a need to use improvements to develop the bearing capacity of anchors, whether single or group, or even if their burial depth is shallow or deep, as is the case with other engineering structures. Method A physical model was used in this experimental research to study the behavior of anchors individually and collectively in sandy soil and how to change the critical depth of burial from shallow depth to deep depth individually and collectively with anchors in addition to the upward bearing capacity in the soil without improvement and also using electronic measuring devices to measure the vertical displacement, and then using bituminous emulsion and recording the values of the uplift bearing capacity of the anchors and comparing them with natural soil. Results In this paper model tests were carried out by using single and line groups square anchor plates (1x2), (1x3), (1x4) & (1x5) in sandy soil with (30) different embedded ratio (H/D) test to understand the behavior of the anchor plate in sandy soils depending upon on the transition from shallow to deep anchor, also to obtain the transitional depth by which the anchor acts as a shallow or deep while in loading state. Depending on the tests the critical depth in the line group ranges from (5D) to (6D), while using a single anchor the critical depth is approximately more than (5D). The other (10) tests were carried out for improving the soil around the anchor by emulsion asphalt at depth (2D) & (6D) shallow and deep respectively. The optimum ratio of the emulsion asphalt was from (4-6)% by direct shear and unconfined pressure tests. The ultimate capacity was improved at high ratio for shallow single anchor than deep single anchor. The use of asphalt emulsion with a 21-day curing period resulted in an increase in the uplift capacity of both the individual anchors and the group. On the other hand, the uplift capacity of the anchor was increased with the use of asphalt emulsion with a 21-day curing period. Furthermore, the uplift capacity of the individual anchor was lower than that of the group of anchors, while the improvement in the shallow anchors resulted in a higher increase in uplift capacity than the deep anchors. Conclusions After conducting laboratory experiments on sandy soil with anchors installed in it and at different depths, it was found that there is a critical depth for the anchors at which the depth moves from shallow to deep. Also, the improvement with bituminous emulsion led to an increase in the load-bearing capacity of the anchors when lifting.
Muhammed et al. (Sat,) studied this question.