Especially for the dredging industry in the United States of America and the leading dredging company Great Lakes Dredge & Dock Company the clamshell dredge is a commonly used dredge tool. The aim of this study was production [m3/s] optimization of the clamshell bucket for stiffer clays. Different aspects of clamshell bucket geometry to clay experiments and bucket concepts are discussed and presented in the report. The approach of tackling this challenge was first evaluating four main elements of the clamshell bucket. These elements were: bucket geometry, bucket kinematics, the cutting process and the soil properties. Questions arose during the cutting process examination and its normative parameter, cohesion and adhesion. At the transition zone for rock to clay with strength of 400 kPa the adhesive strength is zero, because rock is no adhesion and therefore the adhesion has to decrease to zero. With this boundary condition the prediction was made that with increasing cohesive strength there is a decrease of adhesive strength with clay. As assessed the adhesive strength property of clay has a dominant role in the clay cutting process. The correlation between increasing cohesive strength and possible decreasing adhesive strength is of importance for fully grasping the clay cutting process with clamshell buckets or other dredging tools. For this an adhesive measuring test set-up has been designed, constructed and used at Texas A&M. The test set-up was able to pull a steel blade out from two layers of clay and measured the resistance force with an inline load cell connected to an electric actuator. A total of 56 experiments were done at two different pulling speeds, 8 and 0.4 mm/s, on three different natural field clays. The natural field clays were retrieved from two project sites. The first is the softer (10 kPa) Delaware River clay from Philadelphia, Pennsylvania and the stiffer grey (17 kPa) and red (87 kPa) clay from Freeport, Texas. Additional testing was done with Atterberg limits, UU-traxial and mineralogy determination. A clamshell bucket sensitivity analysis was conducted on two existing GLDD buckets to evaluate parameters that influence the production in m3/s. The GL485, an Anvil-Owen, 16 m3 and 24.5 ton and the GL484, Hawco, 9 m3 and 29.5 ton buckets were used. These two grabs were subjected to the variation of the normative parameters: cutting angle, adhesive cutting length, centre point of gravity, bucket weight, bucket span and bucket width. This analysis was done with the Clamshell Closing Simulation software (CCS32). The software can be used to make estimates on bucket payloads, forces, bite profiles in soil and the ability of varying different bucket parameters. These parameters have different results for the two buckets. The GL485’s production is mostly increased by increasing the bucket weight, lowering and outward moving of the centre point of gravity and reducing the adhesive cutting length. For the GL484 it is slightly different and the most effect on the production is reducing the adhesive cutting length, followed by increasing the bucket weight and increasing bucket span for increasing the production. With the acquired data from the adhesive experiments and clamshell bucket sensitivity analysis different clamshell bucket concept designs were created. Of the four clamshell bucket concepts, three (GLX, GLY and GLZ) have their own unique design. These concepts are evaluated with the acquired data of the sensitivity analysis leading to the final concept the GLXYZ. This concept is a combination of GLX, GLY and GLZ and its best features for improving production for every clamshell closing cycle. Each concept is graded with the multi criteria analysis and the concept with the highest overall grade is the best option for new bucket design. The adhesive test set-up with the approaches to the experimental adhesive data has led to confirming the prediction of adhesive strength development with increasing cohesive strength. With an increasing cohesive strength of the clay, there is a decrease to zero for the adhesive strength. In addition to the decreasing adhesion, there is an increase in the internal friction angle (?). This can be concluded from the data of the Freeport grey clay of 17 kPa cohesive strength and the stiffer Freeport red clay with a cohesive strength of 89 kPa with a even smaller adhesive strength. The internal friction angle for the Freeport red clay is 30 degrees, however the internal friction angle will have a limit considering rock has an internal friction angle. This has a major influence on the productions [m3/s] and production estimates of stiffer clays with clamshell dredges or any other dredging equipment.