![]() While the validity of such relationships was not confirmed, as actual measured mud pressure was not known, the relationships seem to be approximate predictors based on the assumed minimum and maximum mud pressures required for circulation and the empirically determined strength properties. ![]() Published analytical relationships are summarized to establish a framework for predicting movements. Because some points moved in different directions at practically the same time, the differential movements in both the vertical and lateral directions exceeded the total. The lateral movements in the N-S and E-W directions fluctuated as well along the N-S and E-W axes. During the advancement of the bore, the direction of the vertical movements fluctuated between heave (upward movement) and downward movement. Differential movements were also observed between points on pavements. ![]() Differential movements in both vertical and lateral directions between points on the concrete deck, abutments, and wing walls of the three bridges were observed. The limiting mud pressures to avoid soil failure and unintended release of mud varied from 57 to 561 kPa. The mud pressure in the bore was not measured, but the calculated minimum mud pressure needed for circulation varied from 32 to 219 kPa. The survey documented downward movements of as much as 19.8 and 12.8 mm heave, and 10.1 mm lateral displacement. During construction, optical surveys were performed to assess movements of the bridge structures, pavements, and other features above and near the bore alignment. This case history pertains to three horizontal directional drilling bores that were advanced under streams and are in close proximity to or beneath three bridges. It’s will also able to educate the stake holders on how important to follow the stipulated technical requirements that contributed to the project success. With the establishment of a thorough and a standard local authority’ technical requirements it’s will able to educate the HDD contractors and assist them in carrying out their work properly, successfully and safely. This study shall able to produce a standard HDD technical requirement and its’ framework. The research design for this study contains the following consist of the research problem and research questions, sampling design, method of data collection, method of data analysis, validation/verification of the HDD standard technical requirements and its’ frameworks. A descriptive and exploratory research design will be used for the study. This research shall use mixed method in achieving the objectives. The aims of this study are to determine the present local authorities’ technical requirements in HDD works, to determine the factors of HDD good practices and to develop a standard HDD’s technical requirement. Since year 1992 up to 2016 there are more than 40 thousand-unit HDD machine were sold worldwide. HDD was developed in California in the 1970s and was introduced in Europe in 1986. It’s called HDD because its steering ability to avoid existing utilities or other obstacles either horizontally, vertically and even pulled back where she got its name. Horizontal Directional Drilling (HDD) is a trenchless technology provides an installation alternative that offers a lot of benefit compared to traditional open-cut method.
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