> For the complete documentation index, see [llms.txt](https://docs.enercalc.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enercalc.com/sel-faq/using-the-software/calculation-modules/walls/slender-walls/bischoffs-method.md). # Bischoff's Method Whether Bischoff's method is code-compliant and how axial load affects the cracking moment. ## Is it per code to use the Bischoff method? Yes, it is per code because the code states that any reasonable analysis method the engineer chooses to use is acceptable. ACI continues to work to get their recommended slender wall methods in line with actual test results. It is well known that the Ieff equation used for over 30 years in slender wall design was incorrect for thin concrete bending members. The Bischoff equation is well known and gives Ieff values far closer to the actual values from test results. We strive for accuracy and have been involved in tilt-up wall panel analyses since 1981 when the first actual tests were performed by SEAOSC. Link to ASCE JOURNAL OF STRUCTURAL ENGINEERING article on Bischoff's method: ## When using Bischoff's method of designing slender masonry walls, is the axial load allowed to be considered when determining the cracking moment? Short answer: No. In the Bischoff-based slender wall method, the cracking moment (M\_cr) is determined from flexural tension only and does not include axial load. Axial load is accounted for elsewhere in the analysis (primarily through P-Δ effects and the applied moment level (M\_a)), but it is not used to modify the cracking moment itself. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.enercalc.com/sel-faq/using-the-software/calculation-modules/walls/slender-walls/bischoffs-method.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.