The SmartBrick platform is an autonomous, wireless, and robust solution for structural health monitoring of civil infrastructures. The base station is currently in its third generation and has been laboratory and field tested in the United States and Italy. The platform has been presented in our previous publications; the focus of this paper is on recent developments made with the objective of complying with military standards for hardware, software, and communication. Specifically, we discuss the design and implementation of the second generation military-standard wireless sensor node for the SmartBrick platform, to facilitate its use in military applications, where interoperability, robustness, and reliability are of paramount concern. Two major enhancements to the sensor nodes are described in this paper. The first improvement is migrating from the DSPIC30F series to the latest DSCPIC33F series of microcontrollers. The second major improvement to the sensor node is replacing the Texas Instrument CC2480 Zigbee transceiver module with the MRF24J40MA from Microchip. These improvements have resulted in significantly lower power consumption and a longer communication range. We articulate the details of hardware and software development of the sensor node that incorporates this chip. We also describe laboratory and field tests, including underwater tests, carried out for validation of reliable operation and performance of the system.